Government's own figures show the Green Deal will be far less effective than existing energy efficiency measures

The previous post on this site looked at whether the flagship Green Deal programme was likely to achieve success. It asserted that the so-called Golden Rule – the requirement that the cost of a home energy efficiency programme be covered by the savings on utility bills – would only be met by cavity wall insulation measures. When I wrote that piece I hadn’t read the long Impact Assessment that accompanied the recent DECC consultation document. The projections in the Impact Assessment show extremely low levels of expected takeup of Green Deal measures.[1] The number of new cavity wall insulations is projected to fall from an average of about 500,000 per annum over recent years to about 100,000 a year at the start of the Green Deal, a reduction of 80%. And cavity wall insulation is the single most cost-effective home improvement (other than loft insulation in one of very small number of homes without any at all).

These are shocking figures. In effect, the government is admitting that the Green Deal will not result in a substantial number of home energy efficiency improvements.  It would have been better to stay with the existing programme of support.

The chart below is taken from page 17 of the recently published DECC Impact Assessment, a 300 page document that is intended to demonstrate the effectiveness of the new programme.

Figure 1: Historic and projected CWI installations under CERT, the counterfactual and option 1

Notes on this chart.

CWI. Cavity wall insulation

CERT. The existing programme of support for CWI, funded by the energy companies and thus indirectly by consumers

Counterfactual. What would have happened if the Green Deal were not introduced and, very importantly, the CERT scheme is abandoned as planned. Please note that the counterfactual could have been the continuation of CERT.

BAU = Business as usual. The levels of BAU installation after 2012 run at about 30,000 a year. There is assumed to be no subsidy and no Green Deal financing.

Uptake (survey) and Uptake (actual, Ofgem) are estimates of the number of home in which new cavity wall insulation was added in each of the years from 2003. These works were usually subsidised by the Government’s CERT programme, an obligation on energy suppliers (essentially, the Big 6) to provide heavily discounted energy efficiency measures, particularly for poorer households or households containing pensioners.

CERT extension. This number, about 800,000 is the expected number of installations were the CERT programme of subsidised installations to be extended for a further year.

DECC modelling. The expected number of homes installing new cavity wall insulation under the terms of the Green Deal, by which the cost is recouped from future payments added to the household’s electricity bill. The words ‘GD only, no ECO’ mean that only the impact of the Green Deal is estimated and the extra impact of the new subsidy programme, the Energy Company Obligation is not calculated. But the ECO is not primarily intended to subsidise CWI. CWI is meant to be cost-effective and should not require any part of the ECO.

---

[1] Thank you to the two individuals who pointed this chart out to me.

The Green Deal: failure is almost guaranteed

The UK’s houses are poorly insulated. The proposed Green Deal is the central part of the government’s plan to encourage householders to improve the energy efficiency of their homes. Instead of paying for improvements immediately, homeowners will be able stretch their payments over many years, paying less than the savings they accrue through lower energy use. What the government calls the ‘Golden Rule’ is that people will be able to borrow as much as they want as long as the energy bill savings are more than the repayments. Sounds too good to be true? It is. At the expected implied interest rates, only cavity wall insulation achieves a large enough energy efficiency benefit to meet the requirements of the Golden Rule. Except in exceptional cases, no other energy saving measures will save homeowners more than the cost of the improvements. The much heralded Green Deal will be a spectacular flop. In late November, the Department of Energy and Climate Change (DECC) launched the open consultation on the new proposals. A dense 200 page document goes into huge detail on the way the new scheme will be regulated and householders shielded from aggressive sales tactics. The concerns about consumer protection are justified – from autumn 2012 energy advisors selling insulation measures will be trying to persuade homeowners to take on thousands of pounds of debt for insulation measures that make no financial sense if the consumer has to pay anything like a commercial interest rate.

The consultation document doesn’t make any attempt to show that it makes financial sense for householders to invest in energy efficiency by borrowing money. In the many hundreds of pages of dense official reports on aspects of the Green Deal, I haven’t been able to find any analysis that shows how much efficiency improvements will cost or what will be the benefits for the average homeowner. Expectations for the scheme run high at DECC: ‘The Green Deal will put consumers back in control. By 2020, we will have seen a revolution in British property’ says the November document. But it contains no numbers and no calculations. So let’s look at a few figures here – I’m sorry if the arithmetic is a little dense.

How much do households spend on heating?

The typical UK house uses about 14,000 kilowatt hours (kWh) for space heating each year. (The average gas bill is higher but this includes about 4,000 kilowatt hours for cooking and water heating). Today’s prices for kilowatt hours of gas start at around 3.5 pence. (You may pay more – this is the lowest rate I could find for gas from a large supplier). All the space heating needs for the average house can be provided for about £490 per year. We’ll call this a round £500.

The gas we use for heating keeps our rooms warmer than the outside world. In a perfectly insulated house, we’d not need any central heating – the heat from our bodies, the warmth from lights and appliances and the energy from the sun getting in through the windows would keep the house heated. The typical UK house isn’t well insulated and leaks heat in approximately the following yearly amounts.[1] (Fans of this type of data can find much, much more in my book How to Live a Low Carbon Life.)

Walls	6,500 kWh
Windows	3,300 kWh
Ventilation (‘draughts’)	3,300 kWh
Roof (loft)	1,300 kWh
Doors	800 kWh

In addition, the typical central heating boiler loses about 2,500 kWh in hot air expelled to the outside world.

The government has provided a long list of energy efficiency measures that householders could plant to introduce under the Green Deal. These range from air source heat pumps to better central heating controls. But the table above gives a good sense of where the savings might actually be worth achieving. If, for example, the walls of a house could be better insulated then it might be possible to save a large fraction of the average heat loss of 6,500 kWh per annum.  Cutting this in half – approximately what can be achieved by adding insulation to cavity walls - would save 3,250 kWh, saving about £115 a year.

Today, cavity wall insulation is subsidised and it will generally only cost about £250 for the average house. After the Green Deal is introduced, the subsidy will go and the full average cost of about £500-£600 will be applied. But even at this higher level of cost, it makes financial sense for the homeowner to pay for insulation of cavity walls. With an interest rate on the loan of 7%, the insulation pays for itself in 7 years.

Although the expected interest rate that will be charged by commercial providers is never specified by the government, the implied figure has risen from 3% mentioned in the early DECC market research to a couple of examples in the footnotes of the November 2011 consultation document that use the 7% figure. Standard personal loans might cost 11% today, meaning that even the 7% figure may turn out to be optimistic.

The crucial fact is that no other piece of house improvement is financially viable. There is either no payback within twenty years at today’s energy prices (double glazing is a good example) or even a small interest rate renders the energy efficiency measure financially unattractive (such as improving the thickness of loft insulation).

Here’s some numbers to back up these assertions.

Double glazing

Cost of double glazing for a medium sized three bedroom semi-detached house  - perhaps £6,000.

Energy saving if this measures cuts heat loss from windows by two thirds – 2,200 kWh per year.

Financial benefit of energy saving - £77 per year.

Payback – about 80 years, by which time the seals on the glazing will have been lost, reducing the efficiency gains.

Loft insulation

Cost of extra loft insulation. (Almost all homes have at least 10 cm of existing covering) – perhaps £320 including the fee of the Green Deal adviser who has to approve the measure.

Energy saving if this measure cuts heat loss from the loft by two thirds – 870 kWh.

Financial benefit of energy saving - £30  a year

Payback with a 7% interest rate – 21 years.

The other major potential cost saving investments are boiler replacements and solar panel installation. Neither come close to achieving a 20 year payback with an interest rate of 7%. A new efficient boiler pays back in two decades (by which time it will probably have had to be replaced again) with a 5% interest rate  and a typical solar panel installation only works with interest rates of 4% or below. This figure assumes that the proposed Feed In Tariff reductions are actually applied.

The very unhappy fact is that with the exception of cavity wall insulation there is no energy efficiency improvement that a family can take that makes strict sense financially if the household has to borrow to make the change. The government’s hypothesis is that British homes are poorly insulated because people don’t have the ready cash to invest in improvements. Sadly, DECC is wrong. British homes remain badly insulated because it is extremely expensive for most people to make real energy saving improvements and few households will want to take on the burden of more debt when the reductions in their energy bills are so small.

The Green Deal as presently configured by DECC will fail. But we must cut household energy bills and reduce the 25% of UK carbon emissions coming from domestic housing. What should we do? First, we need a national well-publicised programme of free cavity wall insulation, with contractors moving street by street to improve every household.

This won’t happen under the Green Deal: it is a hugely complex and a bureaucratic nightmare even a year before it starts. Just to give one example of the costs imposed: the doorstep advisers established under the Deal will be highly regulated and will have supervisory bodies checking their work. Amazingly, on top of these institutions will be a further regulator superintending the activities of the supervisors. The chance of significant success, even at getting large numbers of houses to install cavity wall insulation, are close to zero when the overheads are so great. Only a countrywide programme of free insulation stands any chance. Simplicity can succeed where the Green Deal will not.

Second, we need to have national scheme for insulating solid wall homes. Even the supporters of the Green Deal know that solid wall insulation does not make financially sense. But such measures can make the single greatest difference to fuel bills in money terms. Millions of solid wall houses need external or internal insulation and a nationwide campaign to train an army of people to do the work would have major potential employment benefits. As the economic situation worsens, a campaign to insulate – for free – all the eight million solid walled homes in the country makes increasingly good sense.

---

[1] The total comes to more than 14,000 kWh because our home heating is supplemented by the heat from lights, people, appliances, hot water and solar energy.

Biochar encourages the growth of winter salads

As part of The Big Biochar Experiment, five weeks ago I planted 40 pak choi seeds in small plastic pots. 20 went into conventional peat-free seed compost and 20 were planted into a mixture of 10% biochar (by weight) and 90% compost.

Biochar helped greatly. 16 out of the 20 biochar seedlings germinated, compared to 11 without biochar. The biochar seedlings are, on average, healthier, greener and have much better root systems. Some of the biochar seedlings had one or more roots 40 cm long when taken out of the plastic pot. None of the non-biochar plants had roots that had grown sufficiently to leave the pot. This difference was very striking indeed.

Why does biochar have these effects? In particular, why should germination rates be better with biochar? Much more work is needed on this, but potential hypotheses include the impact of black biochar increasing the temperature of the soil by absorbing more of the limited autumn sunlight.

I think the far better root development may possibly have arisen because the biochar made the soil less susceptible to waterlogging. When I took the seedlings out of their pots, the biochar-amended oil was loose and friable, probably encouraging the growth of the root system. By contrast, the unamended soil was dense and overly damp. The improvement from the use of biochar might therefore not have been as marked if I had planted the seedlings in a peat-based compost which would have resisted the effect of heavy rain better.

Whether or not biochar works to improve agricultural and horticultural yields is a vitally important question. Biochar is nearly 100% carbon, and it seems to remain in the soil for many generations. If the carbon in agricultural and wood wastes that would otherwise rot and turn into carbon dioxide were permanently stored in soils around the world, humanity's net CO2 emissions could be significantly reduced. Increasing the carbon content of the world's cropped soils by one tonne per hectare a year would sequester about 5% of global emissions. Since the typical hectare of agricultural land produces several tonnes a year of organic wastes in the form of such things as straw and maize stover, this target is certainly possible. Biochar has important other effects such as reducing nitrogen run-off, thus cutting nitrous oxide emissions and decreasing the need for conventional fertiliser.

Peak Stuff - did the UK reach a peak of material consumption in about 2001-3?

Empirical evidence presented in a paper available from this website supports the hypothesis that the UK began to reduce its consumption of physical resources in the early years of the last decade, well before the economic slowdown that started in 2008. (An article about this contention was published in the Guardian on 1st November 2011). This conclusion applies to a wide variety of different physical goods including, for example, water, building materials and paper and includes the impact of items imported from overseas. Both the weight of goods entering the economy and the amounts finally ending up as waste probably began to fall from sometime between 2001 and 2003.[1]

Summary data is provided below. The full paper is here: Peak_Stuff_17.10.11

If correct, this finding is important. It suggests that economic growth in a mature economy does not necessarily increase the pressure on the world’s reserves of natural resources and on its physical environment. An advanced country may be able to decouple economic growth and continuously increasing volumes of material goods consumed and a sustainable economy does not necessarily have to be a no-growth economy.

Summary of data in this paper

CategoryPeak yearDecline betweenpeak and 2007

InputsTotal Material Requirement20014%

Direct Material Consumption20015%

Water (overall)2003/44%

Water (household)2003/44%

Uses of biomassFood (calories per head)About the 1960sTens of percent

Food (grammes of meat per person)20033%

Paper20016%

Textiles*2007May not have peaked

Uses of mineralsCement198426%

Cars200310%

Some fertilisers (P and K)Mid 1980sMore than 50%

Use of fossil fuelsPrimary energy production20013%

Travel20051%

Some fertilisers (N)198740%

WasteOverall wasteEarly part of last decadeTens of percent

Domestic waste per household2002/35%

[1] The decline between 2003 and 2007 occurred at the same time as UK population rose by about 2.4%. Source: ONS population estimates.

Some background facts on UK domestic energy supply

1)      About 60% of UK householders say that they have never switched suppliers. 2)      The number of switchers is tending to fall. 22% of electricity customers switched in 2006, falling to 17% last year. The gas numbers were similar.

3)      Only 13% say that they have recently checked prices.

4)      Ofgem research suggests that ‘5-10%’ of householders ‘proactively’ search for better prices. Up to 90% of people were shown by their consumer research to be ‘disengaged’ or ‘passive’.

5)      The last check by Ofgem indicated that there were about 320 different tariffs available in the UK domestic market (January 2011). This is up from about 170 four years before.

6)      In the last thirty days (to 17.10.11) there have been 18 different tariff changes, of which 15 were initiated by the Big Six domestic energy suppliers. None of these changes affected the standard tariff rates. They were all changes to the hugely complex online rate cards as the suppliers withdrew their most attractive online offers. We can only presume that the main reason for these changes was concern that press comment would pick up on the huge differentials between the best online rates and the standard tariffs still taken by approximately 65% of all UK households.

7)      But even today customers in the Southern Electric supply area would save an average of £251 by switching from the standard tariffs of the Big Six to the cheapest online supplier. As of 17.10.11, the cheapest tariff is provided by small supplier First Utility and its cost for a household using 3,300 kWh of electricity and 16,000 kWh of gas would be about 1,025 compared to about £1,275 for the average standard rate card from the Big Six. The First Utility tariff has no cancellation charge but cannot be used by customers unlucky enough to be on independent gas distribution networks.

The Big Biochar Experiment

 

Heat wood or agricultural wastes strongly in the absence of air and you will eventually get charcoal through the process known as pyrolysis. Charcoal is almost pure carbon. When ground up and then added to the soil as a means of improving fertility or reducing water use, it is known as ‘biochar’. An Oxford company, staffed with academic researchers who work in related fields, is sponsoring a country-wide experiment to see if biochar can help domestic gardeners improve their crops.

Because charcoal is highly stable, it stores carbon for hundreds of years. Scientists such as James Lovelock have suggested that biochar might be a very effective way of storing very large quantities of carbon in the soil that would otherwise have returned to the atmosphere in the form of carbon dioxide. At application rates of 10 tonnes an arable hectare per year – a typical dose on a tropical soil – the world’s entire greenhouse gas emissions would be neutralised by using biochar on less than 10% of the world’s arable land area..

On poor tropical soils, biochar adds to agricultural production, often making a huge difference to yields. It seems to work by encouraging the growth of beneficial micro-organisms and by helping retain moisture. Does biochar improve yields in temperate climates? The data is less convincing than for hot countries with naturally carbon-poor soils. Some researchers have demonstrated that biochar can have beneficial impact but the overall effect on yields is much less clear-cut than on degraded soils. But anecdotal evidence is sometimes very compelling. The photograph at the top of this article compares biochar-dosed lettuces on the left with those planted just in conventional composts on the right. (Source: www.thecharlady.com)

The Big Biochar experiment has been designed to produce more evidence like this. The lead researchers from Oxford University’s Environmental Change Institute are distributing 1.5kg bags of biochar to domestic gardeners and people with ‘allotments’, small plots of public land rented to householders on which to grow their fruit and vegetables. Across different soil types, growing varied crops and at different times of the year, we will get an idea whether biochar can help people who cultivate their own food improve their yields. If you want to participate, details are here. You’ll need to pay the postage costs and commit to a trial that compares plant growth on a square metre of biochar-loaded soil to equivalent plants on standard soil.

Cecile Girardin, one of the scientists leading the experiment, is an expert on the carbon cycle in the tropics. (The carbon cycle is the natural process by which carbon dioxide is extracted from the atmosphere by growing plants and eventually returned when the plant dies and rots). She told me that she has a hunch that the experiment will demonstrate that root crops such as carrots or celeriac should benefit most from the addition of biochar to the soil. At this time of year in the UK, plants such as this will not generally be growing. However bulbs such as garlic and onions can be planted now (early October 2011) and will grow slowly through the autumn and winter. I think garlic would be a particularly good crop to use in the experiment. If biochar works, the bulbs should result in stronger stalk growth over the next months. I have done something slightly different, planting pak choi seeds in small pots, half of which have 10% biochar added. I will be looking for differences in root growth and leaf formation after a couple of months.

For those who have become convinced of biochar's virtues, the next step may be to club together to buy a kiln for making biochar. Craig Sams's business Carbon Gold is selling a simple retort for large scale charcoal making. At a cost of £3,500 plus VAT, the kiln is not cheap but garden clubs and allotment associations may be able to afford the investment

Biochar is potentially very important. The evidence is growing that it can both increase yields on some soils, reduce the need for expensive artificial fertilisers and cut losses in drought. The more we experiment the better our knowledge will be and sceptical policymakers will see the advantage of sequestering large volumes of carbon in the world’s soils.

Every large roof in the UK should be adorned by PV

The unexpectedly rapid fall in the cost of large solar PV installations means that the financial returns available to property owners have become highly attractive. Any office block, warehouse or school with a roof that can accept 50 kW of panels can expect a return of over 15% a year on its investment. (PLEASE NOTE: this article was written before the UK government made its deeply damaging decision to reduce subsidy payments from December 10th 2011. The new scale of payments will give returns of about half the figures in this note.)  

The UK review of feed-in tariffs carried out in the spring effectively blocked all installations of a size greater than 50kW. But the payments for smaller systems were unchanged, meaning that the returns to people investing in medium-sized installations, covering perhaps 300 square metres, were untouched by the review.

The cheapest quotations for roof-mounted 50 kW installations are now running at around £2.30 per watt. This means that a full-sized system taking maximum advantage of the tariffs could costs as little as £115,000. In the southern half of England a south-facing installation on a sloping roof should generate at least 850 kWh per kW of panels. Assuming that all the electricity generated is used in the building, the total income from the system will be over £18,000 a year, inflating for the next 25 years at the retail price index (RPI). On a particularly sunny site on the south coast, the annual  income could reach 18.5%, inflation-protected. (Although the maps show Cornwall getting the best solar radiation in the UK, data I have seen from readers of this blog strongly suggests that coastal Sussex, which has more sunshine than almost any where else in the UK although less predicted total insolation than the South West, is almost as good).

These are exceptional returns. Compare them to the recently withdrawn index-linked  bond from UK National Savings offering RPI + 0.5%. Although the National Savings offer is government guaranteed tax free and is repaid in full at maturity, the income is still far below the rate offered by a good PV installation. There really isn’t a good reason for people owning large roofs not to be racing to install PV before the rates go down in April of next year. And if you cannot raise the money yourself, there should be no shortage of return-hungry investors eager to assist.

PS. The good financial returns available to the owners of large PV systems do NOT mean that solar is necessarily a good investment for the UK as a whole. The payments mentioned in this article amount to 42.9 pence per kilowatt hour, including 10p per kilowatt hour for the benefit of not buying grid electricity, and are about ten times the level of today’s wholesale power prices. Although the price of large-scale PV has nearly halved in the last year, it remains uncompetitive with other forms of electricity generation. And this extra cost is still loaded onto all the people in the country not lucky enough to be able to afford PV or living in accommodation without access to a good roof.

Bioplastics: an important component of global sustainability

(This work was commissioned by Biome Bioplastics, a leading European bioplastics company. A formatted version of the paper is available on the company website -www.biomebioplastics.com)

Plastics are a vital asset for humanity, often providing functionality that cannot be easily or economically replaced by other materials. Most plastics are robust and last for hundreds of years. They have replaced metals in the components of most manufactured goods, including for such products as computers, car parts and refrigerators, and in so doing have often made the products cheaper, lighter, safer, stronger and easier to recycle.[1] Plastics have taken over from paper, glass and cardboard in packaging, usually reducing cost and carbon emissions while also providing better care of the items that they protect.[2][3]

But we all know about the counterbalancing disadvantages.

• Plastic litter disfigures the oceans and the coastlines. Ingestion of plastic kills marine creatures and fish. Perhaps 5% of the world’s cumulative output of plastic since 1945 has ended up in the oceans. Shopping bags and other packaging are strewn across the streets and fields of every country in the world.
• Plastics use valuable resources of oil
• The plastics industry uses large amounts of energy, usually from fossil fuel sources which therefore adds to the world’s production of greenhouse gases.
• The durability of plastics means that without effective and ubiquitous recycling we will see continuing pressure on landfill. Although plastics do not represent the largest category of materials entering landfill – a position held by construction waste – they are a highly visible contributor to the problems of waste disposal.
• The manufacturing of conventional plastics uses substantial amounts of toxic chemicals.
• Some plastics leach small amounts of pollutants, including endocrine disruptors, into the environment. These chemicals can have severe effects on animals and humans. (The solution to this problem is to avoid using original raw materials - either monomers or plasticizers -that might produce such compounds when the plastic is in use or has been discarded).

The world needs to find a solution that gives us continued access to plastics but avoids these serious problems.  Bioplastics - partly or wholly made from biological materials and not crude oil - represent an effective way of keeping the huge advantages of conventional plastics but mitigating their disadvantages.

What is a bioplastic?                                                                                                                                              

A bioplastic is a plastic that is made partly or wholly from polymers derived from biological sources such as sugar cane, potato starch or the cellulose from trees, straw and cotton. Some bioplastics degrade in the open air, others are made so that they compost in an industrial composting plant, aided by fungi, bacteria and enzymes. Others mimic the robustness and durability of conventional plastics such as polyethylene or PET. Bioplastics can generally be directly substituted for their oil-based equivalent. Indeed, they can generally be made to be chemically identical to the standard industrial plastics.

In thinking about the potential role of bioplastics, we need to distinguish between two different types of use.

• Items that might eventually become litter – such as shopping bags or food packaging – can be manufactured as bioplastics to degrade either in industrial composting units or in the open air or in water. Strenuous efforts need to be made to continue to reduce the amount plastic employed for single use applications. But if the world wishes to continue using light plastic films for storage, packaging or for carrying goods, then the only way we can avoid serious litter problems is to employ fully biodegradable compounds.[4]

• Permanent bioplastics, such as polythene manufactured from sugar cane, can provide a near-perfect substitute for oil-based equivalents in products where durability and robustness is vital. Plastics made from biological materials generally need far smaller amounts of energy to manufacture but are equally recyclable. They use fewer pollutants during the manufacturing process. Per tonne of finished products, the global warming impact of the manufacture of bioplastics is less, and often very substantially less, than conventional plastics.

Plastics are regarded with deep ambivalence in the much of the world. Their association with indestructible and unsightly litter sometimes blinds us to their enormous value. Bioplastics – with a low carbon footprint and the capability of being made to completely degrade back to carbon dioxide and water – are a vital and growing complement to conventional oil-based plastics. They can be made to completely avoid the use of the monomers and additives that may have effects on human or animal health. As oil becomes scarcer, the value of bioplastics will increase yet further.

Plastics

About 4% of the world’s oil production is converted into plastics for use in products as varied as shopping bags and the external panels of cars. Another few percent is used in processing industries because oil-based plastics require substantial amounts of energy to manufacture. Each kilogramme of plastic typically requires 20 kilowatt hours of energy in the manufacturing process, more than the amount needed to make steel of the same weight. Almost all this comes from fossil sources. One survey suggested that the plastics industry was responsible for about 1.5% of allUSenergy consumption.

As oil runs out, and the use of fossil fuels becomes increasingly expensive, the need for replacement sources of raw material for the manufacture of vital plastics becomes increasingly urgent.  In addition, the use of carbon-based sources of energy for use in plastics manufacturing adds greenhouse gases to the atmosphere, impeding the world’s attempts to cut CO₂ emissions.

These problems can be overcome. All the major oil-based plastics have substitutes made from biological materials. The polyethylene in a shopping bag can be made from sugar cane and the polypropylene of food packaging can be derived from potato starch. Plastics are irreplaceable and will all eventually be made from agricultural materials.

The world plastics industry and the role of bioplastics.                                                                             

The annual output of the world’s plastics industry is about 225 million tonnes a year.[5] This number has grown by a few per cent per year over the last decade. The bioplastics industry is much smaller, with 2011 probably seeing a total output of about 1m tonnes, or less than half of one per cent of total world plastics output. But the growth rate of bioplastics is much higher. Most sources suggest that this part of the plastics industry is growing at least 20% a year. The reasons for this buoyancy are discussed later in this note.

Not even the most fervent advocates of the bioplastics suggest that they will quickly replace all oil-derived compounds though most people expect rapid growth to continue.

• They are generally two or three times more expensive than the major conventional plastics such as polyethylene or PET. This disadvantage will tend to diminish as bioplastics manufacturing plants become larger and benefit from economies of scale. When the local biological feedstock is particularly cheap, as it is in Brazil, large bio-polyethylene plants may already be close to being cost-competitive with oil-based alternatives.[6] But more generally, the crude oil for a kilo of plastic costs around €0.20 but the corn, a key source of feedstocks for bioplastics currently (August 2011) costs about twice this amount.
• Their physical characteristics are not always a perfect substitute for the equivalent polymer. Sometimes the differences are trivial, such as the biological version having a slightly different texture, but in some cases the bioplastic cannot substitute for the conventional plastic. But for the most important plastic – polythene – the product based on biological sources is identical to the plastic made from oil.
• There are a huge number of different market segments in which bioplastics can compete. In some cases, bioplastics are likely to make substantial inroads into share of traditional plastics while in others they will struggle. Novamont, the leading Italian bioplastics company, has estimated that biodegradable plastics can replace about 45% of the total sales of oil-based plastics in horticulture and 25% of those used in catering. Others regard these estimates as too low.
• The Committee of Agricultural Organisations in the European Union suggested a figure for the accessible market for bioplastics in the EU alone at around 2m tonnes, several times the current production level. It sees the most important single segment as catering products, such as single use cutlery, followed by vegetable packaging.

Bioplastics versus food

In many types of applications, bioplastics offer substantial advantages over conventional products. Nevertheless, despite their relatively minor current role, one serious issue does need to be addressed, both now and in the future.

At the moment many bioplastics are made from sugars and starches harvested from crops that otherwise might be grown for food. As with liquid biofuels, the bioplastics industry has to deal with the vitally important question of whether the growth of bioplastics will tend to decrease the land available for food production, or increase the incentive to cut down forested areas to create more arable land. Cutting down forests is bad for global warming - because it returns carbon to the atmosphere - and bad for the wider environment because it tends to decrease biodiversity and increase erosion and flooding.

At present, the world bioplastics industry produces about 1 million tonnes of material. Perhaps 300,000 hectares are used to grow the crops which the industry processes into plastics.[7] For comparison, this is about 0.02% of the world’s total naturally irrigated area available for cultivation.[8]  Even if half the world’s plastics were made from crops grown on food land, the industry would only require 3% of the world’s cultivated acreage. By contrast, the bioethanol industry in the US uses over one tenth of the country’s arable acres to grow corn, but this fuel provides less than 10% of total liquid transport fuel. Biofuels are already an order of magnitude more important than bioplastics will ever be in using the world’s productive land.

How important is this issue?                            

The impact of the growth of bioplastics on the land available for growing food and on maintaining forest cover is an issue that needs to be openly discussed, as it is with the use of foodstuffs as feedstocks for biofuel refineries. But the world’s plastic industry is only about one tenth the size of the transport fuels sector in terms of its use of oil. If today’s entire plastics production was made from biological sources it would consume between 0.1% and 0.2% of the globe’s total annual production of organic matter (‘net primary production’). This is not a trivial amount but concerns about the competition for land need to be balanced by consideration of the enormous potential value of making bioplastics compared to the equivalent oil-based plastics.

In fact, the position is even less threatening. First, bioplastics are often made from products that would otherwise be wasted because they are unusable for human consumption. Potato starch is a by-product of some food production processes. As well as for bioplastics, this product – a waste that would otherwise have to be disposed of – is used for products as diverse as a constituent of drilling mud for oil and gas exploration and as a wallpaper paste. Plastics applications are only ever likely to be a small portion of total demand for this source of biological starch.

Sugar cane for bioplastics is usually grown on land in Brazil that has few alternative uses and certainly could not be used to grow grains. Furthermore the energy used to power the manufacturing process that creates the bioplastic from sugar is provided by the combustion of the stalks and leaves (‘bagasse’) of the cane, and no fossil fuel is used. Sugar cane is also the primary source of Brazil’s bioethanol which provides much of the country’s transport fuel. The crop is grown on dry lands, often used previously for cattle pasture but now so degraded that it cannot be used for any other form of intensive agriculture. There is no risk of sugar plantations encroaching on the precious Amazonian rain forest, which is over two thousand kilometres away from the land used for growing sugar cane. Braskem, the Brazilian company that is the largest plastics producer in the Americas, has just established a 200,000 tonne biopolyethylene plant (equivalent to about 20% of the world’s current bioplastics production) and states that growing the feedstock for this factory will use less than 0.1% of all Brazilian arable land.

Furthermore, as technology improves industry participants will have a much wider variety of raw material sources to use to make bioplastics. It will eventually be unnecessary to use land that might otherwise have been used for food. The list of potential alternative feedstuffs includes algae, which grows in water rather than on land, and cellulose. The cellulose molecule, which is the most abundant carbon-containing molecule in the natural world, forms the bulk of the weight of trees and of agricultural wastes such as straw. It was also the basis of the first commercial plastic, Parkesine, which was patented in 1856, and other historically important plastics such as celluloid. As oil becomes scarcer and more expensive the move back to cellulose and other biological feedstocks will represent a return to the days before the abundant availability of cheap petrochemicals.

Biome Bioplastics has traditionally focused on using potato starch as the main feedstock for its products. But as an illustration of the trend towards new feedstocks, nine out of the twelve new products launched this year have used non-starch polymers. The research and development needs to continue in the laboratories of bioplastics companies around the world.

As Dr Anne Roulin, the global head of packaging and design at Nestle, says when referring to the need to develop cellulose and other bioplastic polymers, ‘I think it is going to be an evolution where we will continuously reduce environmental impact and find more energy efficient processes. But I really see the trend going in the direction of conventional plastics made from renewable resources’.[9]

Finally, we need to consider the impact of improved recycling. Until a few years ago, the amount of plastic recycled was tiny. The costs of separating and cleaning different types of plastic were too high. Advances in recognition technology  - usually using infra-red or ultra-violet sensors to identify each of the key types of plastic – are enabling recyclers like Lincolnshire-based Eco Plastics to sort, clean and then resell almost all types of plastic. Their Hemswell plant has a total capacity equivalent to almost 5% of the UK’s total plastic consumption and enabling Coca Cola, for example, to source an increasing fraction of its total need for plastic from recycled PET, whether initially made from oil or from starch.[10]

About 25% of the UK’s plastic is now recycled and this can continue to rise strongly in the next few years, with the only obstacle being a shortage of state-of-the-art facilities like Hemswell. Why are we stressing the importance of the recycling of non-biodegradable plastics, whether from oil or from plant matter? Because the world needs to be more economical in its use of its scarce resources. Whether this is the oil used for most plastics or the starches, sugars and cellulose for biological plastics, we cannot afford to continue to throw away three quarters of the plastic we use. A swing towards biologically-sources plastics should not mean any let up in the move towards near-100% recycling of all types of plastics, whether made from oil or from agricultural wastes.

The benefits from using bioplastics

a)      Major consumer goods brands and bioplastics

Over the last five years many of the world’s largest consumer good companies have begun to employ bioplastics in the packaging of their products. Examples include Coca Cola’s use of a mixture of a conventional plastic and bioplastic in its soft drink bottles, Proctor and Gamble’s bioplastic shampoo packaging and Nestle’s adoption of a bioplastic top for his Brazilian milk products.

Coca Cola’s PlantBottle uses petroleum PET and up to 30% plant-based equivalent. The bottle can be reprocessed through existing recycling facilities in exactly the same way as other PET bottles. Coca Cola aims at using bottles that are ‘made with 100 per cent plant-waste material while remaining completely recyclable’, according to Scott Vitters, director of sustainable packaging at the company.

Coca Cola recognises the danger of raw material production for bioplastics diverting farmland away from the production of food or resulting in the loss of woodland. But the newsletter Business Green reported comments from Dr Jason Clay, senior vice president of market transformation for the WWF, saying that Coca-Cola had taken precautionary measures to ensure its bio-plastic does not inadvertently lead to deforestation and increased emissions.

‘Coca-Cola is currently sourcing raw materials for its PlantBottle from suppliers in Brazil, where third parties have verified that best-in-class agricultural practices are the norm," he said. ‘Preserving natural resources through sustainable agriculture is essential for businesses like Coca-Cola as they search for ways to alleviate environmental challenges.’[11]

Jason Clay of WWF also has warm words for Proctor and Gamble’s new polyethylene biopackaging, also made from sugar cane sourced from Brazil. ‘P&G's commitment to use renewable bio-derived plastic in its global beauty and grooming product packaging is an important step forward in its efforts to improve the environmental profile of its products,’ he said.[12]

Nestle is also moving rapidly towards the increased use of bioplastics, saying publicly in July 2011 that it ‘is involved in over 30 projects to introduce bioplastics in its product packaging portfolio worldwide.’[13]  In early 2011, the company launched packaging made from renewable resources for its pet food packaging in the US.

The introduction of renewable and recyclable packaging hasn’t been problem free everywhere. SunChips, a subsidiary of PepsiCo’s Frito-Lay snacks unit, recently stopped using an early version of a compostable packaging film for most of its products. The plastic film made from PLA – a renewable plastic made from corn starch – was regarded as ‘too noisy’ by customers. But SunChips didn’t lose its commitment to compostable plastic packaging. Instead its web site says that ‘we’ve created a new, quieter fully compostable chip bag that’s easy on the ears. Our new quieter compostable plastic bag will be rolling out over the next month’.[14] (We believe that the new packaging is still made from PLA) On the parent company’s web site, the statements continue to stress the importance of renewable plastic films.  ‘There’s enormous opportunity to reduce our use of non-renewable resources by using plant-based materials,’ says Tony Knoerzer, Frito-Lay’s Director of Sustainable Packaging.[15]

These four companies are among the biggest consumer goods companies in the world, with operations in almost every country. All of them appear to be committed to an increase in the use of bioplastic packaging for their products. Their reasons are simple: these businesses are watching the actions and attitudes of their customers who are increasingly concerned about the use of fossil fuel resources and, particularly, about indestructible litter. Bioplastics are important in helping consumer goods companies present their brands in a favourable light. Recyclable or compostable packaging made from biological materials can be used to make their products more environmentally friendly in the eyes of consumers. Although bioplastics may be more expensive per kilo of packaging, the extra cost is more than outweighed by the benefits seen by purchasers. The client lists of the major bioplastic suppliers include most of the largest and best-known consumer goods companies, ranging from the Shiseido cosmetics brand to Ecover, the Belgian cleaning products company.

In addition, large companies like these are becoming more aware of the risk of disruption to the supply of oil-based plastics. In order to ensure that at least part of the operations could continue after a loss of availability of conventional plastics - perhaps because of an oil embargo – many large and responsible companies are investing now in developing bioplastic packaging.

b)      The value of the reduction in landfill/expensive preparation for recycling

Some bioplastics are as robust and durable as their oil-based equivalents. Others will rapidly break down in commercial composting plants. These rapidly biodegradable plastics have high value in some circumstances such as when plastics become inevitably mixed with other streams of compostable waste and would otherwise need to be hand separated. For example, quantities of plastic material are used in greenhouse applications. A productive application for bioplastics is the ties that hold tomato vines to the support wires in commercial greenhouses. After the crop is concluded, the waste organic material, including the ties and other plant-based plastics such as the small pots in which plants are grown as seedlings, can be quickly and efficiently cleared and taken to be composted. Conventional plastics would have to be separated by hand at great expense and usually then sent to an incinerator or landfill.

A more substantial application also arises in the horticultural sector. Many field grown vegetables are covered in a thin semi-transparent polypropylene mulch to help maintain even temperatures, reduce water loss and protect the crop from insects. The mulch generally only lasts for one season and then it has to be collected up and returned for recycling. This is a complex and expensive process. A bioplastic mulch that will dissolve in the soil over the winter is much better because it saves time and money but also adds to the carbon content of the soil, helping to maintain fertility. In other important agricultural uses, such as for strimmer cord (‘weedwacker’ in the US, full biodegradability means that small pieces of plastic filament do not persist in the environment.

Another example, likely to become one of the largest single applications for bioplastics, is single use catering utensils. Restaurants and coffee shops generate three streams of waste: unused food, packaging (for example of sandwiches) and utensils such as cutlery. It is highly beneficial – as well as being advantageous to the brand image of the restaurant – to use fully compostable packaging and utensils. All the waste can be put into one bin and shipped to the composting facility without further intervention or labour cost. The thick pieces of plastic cutlery will need to shredded at the composting site to encourage rapid biodegradation but this can happen automatically. Although fully degradable cutlery costs about four times as much as conventional plastic utensils, the reduction in time spend separating out plastics from food waste and,second, reducing landfill cost, more than justifies the expense.  As well as compostable utensils, it makes sense to use bioplastic film to provide the windows in cardboard sandwich packets so that the packaging can also be added to the stream of compostable items.

Some American towns and cities are beginning to move to mandatory use of biodegradable plastics for single use catering utensils, including plates, cups and cutlery. Seattle, for example, has introduced an ordinance that obliges restaurants to only use bioplastics that will degrade in the city’s composting plant. The final imposition of this rule has been delayed by problems obtaining cutlery that is sufficiently compostable but the rules are becoming stricter here and in other towns and cities wanting to reduce use of landfill.  Seattle uses a landfill site 320 miles from the city - about the distance from Newcastle to London - creating a huge incentive to avoid high transport fees.[16] As disposal sites fill up around the world, the need either to recycle plastics or to compost them can only increase, adding further buoyancy to bioplastic sales.

In a similar move, municipalities around the world collecting food waste from homes are now often providing compostable plastic bags into which the food goes prior to collection. Householders benefit from easier and more hygienic storage of the waste. The municipality can collect the bag and does not have to separate it from the waste food before the composting process begins. While these bags are not as strong as the equivalent standard polyethylene bag, they perform their functions well.

c)       Litter

The best understood advantage of biodegradable bioplastics lies in the reduction of permanent litter. Plastic single use shopping bags are the most obvious example of how plastics can pollute the environment with huge and unsightly persistence. A large fraction of the litter in our oceans is of disposable plastic bags. Cities and countries around the world are taking action against the litter, sometimes by banning non-degradable plastic bags entirely. Italy has decided to block the use of non-biodegradable single use shopping bags from the beginning of 2012. The city of Portland, Oregon has just (July 2011) joined several dozen US municipalities in banning most plastic bags. These legislative changes represent a clear trend as politicians respond to the irritation over the persistence of plastic bag litter in the world’s seas, rivers and rural and urban environments.

Some places will continue to allow plastic bags that are genuinely biodegradable and meet the published standards for compostability. (Bags that are oxy-degradable, and only break down in to very small pieces rather than truly biodegrading, will generally be banned). Biodegradable bioplastic bags will be allowed in Italy, providing a huge boost to the European market for these products not least because until now the country has been the largest European market for single use shopping bags.

Bioplastics demand will continue to grow.                                                                                     

Continued research and development in bioplastics is creating high quality products for a wide variety of industries. Now that the benefits of biologically sourced plastics are well-understood, their market share is likely to rise sharply. The three drivers of growth – the importance of brand image to consumer goods companies, the value of joint composting and the reduction of litter – will provide the spur for continued growth in bioplastics across the world.

The carbon footprint of plastics

Calculating the greenhouse gas reductions arising from the use of bioplastics is a complex and controversial area. But it is nevertheless important to try to quantify the benefits from making plastics from biological materials in order to encourage further debate and research.

The first point to make is that the carbon footprint of a bioplastic is crucially dependent on whether the plastic permanently stores the carbon extracted from the air by the growing plant. A plastic made from a biological source sequesters the CO₂captured by the plant in the photosynthesis process. If the resulting bioplastic degrades back into CO2 and water, this sequestration is reversed. But a permanent bioplastic, made to be similar to polyethylene or other conventional plastics, stores the CO₂ for ever. Even if the plastic is recycled many times, the CO₂ initially taken from the atmosphere remains sequestered.

The chart below offers illustrative figures for the greenhouse gas impact of making a kilo of bioplastic from a material such as wheat starch. The first column – a negative number - estimates the CO₂ captured from the atmosphere by photosynthesis during the growth of the plant. The second records an estimate of the greenhouse gases emitted in the process of producing the wheat. This includes the emissions from fossil fuels used to power the tractor and other energy use in the field and in the drying of the wheat. It also measures the impact of fertiliser manufacture and the emissions of nitrous oxide, a very powerful global warming gas, as a result of the chemical breakdown of nitrogenous fertiliser in fields.

The third column estimates the CO₂ impact of the energy used in converting the starches to a plastic. This figure will generally be much lower than the figures for oil-based plastics because biological materials need much lower temperatures and pressures in the manufacturing process. Bioplastics can generally be processed at about 140-180 degrees Celsius compared to temperatures of around up to 300 degrees for conversion of petrochemicals to plastics.

Chart A

The greenhouse gas implications of making a simple polymer plastic from wheat

(These numbers are illustrative – kilogrammes of CO₂ equivalent per kilogramme of plastic produced)

-1.4 CO2 sequestration by growing plant

+0.6 GHGs emitted by farming

+2.0 GHGs produced by conversion to plastic

+1.2 Net carbon footprint

Sources: Sequestration in wheat, http://ec.europa.eu/environment/ipp/pdf/ext_effects_appendix1.pdf, GHGs from wheat cultivation, ’How Bad are Bananas’ Mike Berners Lee, Profile Books, 2010, GHGs from conversion processes, estimate from Biome Bioplastics. CO₂e is a measure of emissions by which all different greenhouse gases are standardised to the global warming impact of CO2.

Most calculations of the energy used and greenhouse gases created in the production of conventional plastics produce much higher numbers. One estimate of the CO₂ produced per kilogramme of oil-based polypropylene is 3.14 kilogrammes per kilogramme of plastic.[17]  This compares with the 1.2 kg illustrative figure for wheat polymers in the chart above.  To be clear, the implication is that those bioplastics that do not degrade might therefore have a carbon footprint of well under half the conventional equivalent.

Braskem, the large Brazilian producer manufacturing both bioplastic and oil-based equivalents, has calculated much higher figures for the capture of CO₂ by a growing sugar cane plant. It estimates a net sequestration (that is, a negative footprint) of about 2.3 kilogramme of CO₂ for every kilogramme of biopolypropylene manufactured.[18] It compares this to a carbon footprint of over 3 tonnes for polypropylene made from oil, meaning a net gain of over 5kg of CO₂ for each kilogramme of plastic. This is an important potential saving; if all plastics were switched to biological feedstocks and the carbon footprint benefit was as high as much, the reduction in global greenhouse gas emissions would be about 5% of current total.

If, on the other hand, the bioplastic is of a degradable type the advantages over conventional plastics are less pronounced. The plastic will compost back into carbon dioxide and water, returning all the sequestered carbon to the atmosphere. In the illustration given above, the savings from making the bioplastic compared to the oil-based comparator would be relatively small, but nevertheless still positive. The crucial point – not well understood by commentators or by the public – is that compostable plastics will typically have a much larger carbon footprint than ones that are manufactured to be permanent. The return of the CO₂ to the air reduces the sequestration of organic material.

This situation would be made worse if the bioplastic did not compost in air, but rotted in an oxygen poor landfill. In these circumstances, the plastic would degrade into methane (CH₄) and other byproducts. Methane is a global warming gas of greater impact than CO₂ and so the full carbon footprint needs to include any uncaptured CH4 produced in landfill.[19] Most - but not all - research shows that the conditions in well maintained landfill sites are too dry for degradable plastics to actually rot. In these circumstances, the bioplastics will therefore permanently sequester carbon. More work needs to be done on this issue, but in the intervening time the precautionary approach is to try to ensure that all biodegradable bioplastics are kept out of landfill.

The other advantages of bioplastics

We have identified five major advantages of bioplastics in this note

• Potentially a much lower carbon footprint
• Lower energy costs in manufacture
• Do not use scarce crude oil
• Reduction in litter and improved compostability from using biodegradable bioplastics
• Improved acceptability to many households

There are also some significant technical advantages to bioplastics; these depend on the precise plastic used and how it is made. Products characteristics of value can include

• Improved ‘printability’, the ability to print a highly legible text or image on the plastic
• A less ‘oily’ feel. Bioplastics can be engineered to offer a much more acceptable surface feel than conventional plastics
• Less likelihood of imparting a different taste to the product contained in a plastic container. Milk, for example, will acquire a new taste in a styrene cup but the bioplastic alternative has no such effect.
• A bioplastic may have much greater water vapour permeability than a standard plastic. In some circumstances, such as sandwich packaging, this can be a disadvantage, but in the case of newly baked bread a bioplastic container will offer a significant advantage in letting out excess vapour or steam.
• A bioplastic can feel softer and more tactile. For applications such as cosmetics packaging, this can be a major perceived consumer benefit.
• Bioplastics can be made clearer and more transparent (although they are usually more opaque)
• Plastics made from biological sources still need to contain additives such as plasticisers that give the product its required characteristics. But bioplastics do not contain bisphenol A, an additive thought to leak from plastics and which is an endocrine disruptor and mimics sex hormones. Bisphenol A is not yet banned in most countries because the chemical is rapidly excreted by most creatures, including humans. But the high levels of continuing exposure to this worrying chemical from conventional plastics may mean that consumers will want to avoid this chemical and shift to safer bioplastic alternatives.

Bioplastics are an important part of the move to a more sustainable world.                            

Bioplastics, currently accounting for less than half of one per cent of all plastics manufacture, are growing rapidly because of the clear advantages they have in many applications. As oil supply tightens, these advantages will grow. Their carbon footprint can be much lower than oil-based equivalents.  Bioplastics can provide excellent biodegradability, helping the world deal with the increasing problems of litter, particularly in the world’s rivers and seas. Durable plant-based bioplastics can also be recycled as well as their conventional equivalents, assisting the growth of a more sustainable world economy.

Chris Goodall

chris@carboncommentary.com

+44 07767 386696

(This research was commissioned by Biome Technologies, a major European bioplastics company. A full version is available at www.biomebioplastics.com)

---

[1] Comparing the greenhouse gases to make a water bottle, the New York Times reported that steel is fourteen times worse than plastic. (http://www.nytimes.com/interactive/2009/04/19/opinion/20090419bottle.html). G Magazine in Australia suggested that recyclable plastic water bottles had up to 80% less global warming impact than steel or aluminium alternatives http://www.gmagazine.com.au/node/2436/full

[2] Incpen, an industry trade body, provides analysis of comparative carbon footprints for various types of packaging. One example showing that plastics are better than glass is provided here http://www.incpen.org/resource/data/ipen1/docs/PRAG3LCAMeasTools.pdf

[3] The UK Environment Agency produced a report in early 2011 that suggested that supermarket paper bags had three times the environmental impact of single use polyethylene bags. http://publications.environment-agency.gov.uk/PDF/SCHO0711BUAN-E-E.pdf

[4] Some conventional plastics can be made to break down. However readers should be aware that many such plastics, often termed ‘oxy-degradable’, do not actually degrade into smaller molecules. Rather, they simply break into very small pieces. This reduces the visual problem caused by litter, but the wider concerns remain. For example, birds and fish eat the small pieces of plastic, thinking them to be food.

[5] http://www.gtai.com/homepage/info-service/publications/our-publications/germany-investment-magazine/vol-2011/vol-012011/industry-report-4/

[6] Dow Chemical expects its proposed Brazilian bio-polyethylene plant to produce plastic at about the same cost as the oil-based equivalent. http://www.technologyreview.com/energy/38114/

[7] These figures are based on calculations offered by European Bioplastics at www.en.europe-bioplastics.org

[8] Michael Carus and Stephan Piotrowski, Land Use for Bioplastics, Bioplastics Magazine, 04/09

[9] Quoted in European Plastics News, July 26^th 2011. http://www.europeanplasticsnews.com/subscriber/headlines2.html?cat=1&id=1311674045

[10] Details at http://www.coca-cola.co.uk/environment/coca-cola-eco-plastics-recycling-joint-venture.html

[11] Business Green, 17^th November 2009, ‘Coca Cola launches bioplastic PlantBottle.’

[12] Press release from Proctor and Gamble, August 12^th 2010, ‘P&G Announces Plan to Use Innovative Sustainable Packaging’.

[13] Press release from Nestle, July 29^th 2011, ‘Nestlé launches bioplastic caps for milk brands in Brazil’

[14] Text taken from the SunChips website, www.sunchips.com, on August 2^nd 2011

[15] Text taken from Frito-Lay website, www.fritolay.com, on August 2^nd 2011

[16] Information at http://www.seattle.gov/util/groups/public/@spu/@usm/documents/webcontent/cos_001786.pdf

[17] This figure was calculated by Professor Ramani Narayan of Michigan State University in a study for the bioplastics company Cereplast.

[18] This number is contained in this presentation. (Page 15) http://www.braskem-ir.com.br/braskem/web/arquivos/Conference_Mar2011_Citi_1x1_v2.pdf

[19] Many landfill sites in the UK collect the methane from rotting organic materials and burn it for electricity production. Nevertheless some methane escapes and adds to global warming.

The moral case for nuclear power – an article by George Monbiot

George Monbiot and Jonathon Porritt have been engaged in a debate about the merits, or otherwise, of nuclear power. I did some of the research for George’s article on the Guardian website today (August 8th 2011). Like George, I have reluctantly come to believe that the world needs nuclear – and lots of it – if it is produce the energy it needs without carbon emissions. Energy efficiency is important and the development of renewables should continue with enthusiasm and financial commitment. But the task of getting to 100% replacement of fossil fuels is so enormous, so intimidating and so expensive that I think countries need to encourage nuclear power as well as renewables. One calculation I made George didn’t have the space to use so I have written about it here.

Jonathon Porritt praised the German decision to phase out nuclear rapidly and increased emphasis on solar PV. Porritt gave the impression that PV in Germany costs about the same price as conventional electricity. The reality is very different. As in the UK, the subsidy to renewables is spread across the all electricity users and the solar feed in tariffs in Germany are adding rapidly to the costs faced by power users, rich and poor.

The 2011 levy on German customers’ bills to meet the subsidies to renewable energy is about 3.5 cents a kilowatt hour. The figure increased by almost 1.5 cents a kilowatt hour over 2010 and most of this increase was due to what one source describes as the ‘skyrocketing’ costs of PV subsidies. (1) The net effect on typical German household bills of all the subsidies of renewable energy sources is now about £150 a year, of which about half is the payment for solar energy. Translated to the UK, the German renewables subsidy would be adding about 25% to customers’ bills, pushing millions more into fuel poverty.

All low carbon sources are going to be more expensive than fossil fuel and we shouldn’t even pretend otherwise. But he problem with solar is that in cloudy countries like the UK and Germany it requires a huge amount of capital and produces small amounts of electricity. Per unit of electricity generated, PV requires about five times more subsidy than wind.

The German PV subsidy will cost about €8bn this year, payable by all electricity users. And this will continue each year for decades, increasing with every new installation of PV panels. Current PV installations only produce about 2% of the country’s electricity, about the same as would be produced by one new nuclear power station. Just one year’s PV subsidy would pay for the construction costs and the lifetime operating expenses of a nuclear power station. There would be no further cost to consumers. But the same amount of PV generating capacity needs €8bn a year into the indefinite future  Do German consumers realise PV electricity is costing them literally an order of magnitude more than nuclear energy?

(1) http://www.germanenergyblog.de/?p=4249

Government statisticians not certain greenhouse effect actually exists

UK government statisticians put out a report today that includes a section on the effects of climate change. The Office for National Statistics document contains three bizarre comments that suggest they simply don’t understand the science. Is scepticism about the reliability of the laws of physics beginning to infect even central government? Will we get a note from ONS next week suggesting that existence of gravity is still subject to scientific dispute? 1, 'Some studies of long-term climate change have shown a connection between the concentrations of key greenhouse gases – carbon dioxide, methane and nitrous oxide - in the atmosphere and mean global temperature'.

No, not ‘some’ studies.  All research ever conducted into long-term climate change has shown not just ‘a’ connection between greenhouse gases and temperature but a very strong link. The level of CO2 in the atmosphere is highly correlated with global temperature across the last hundreds of millions of years.

2, 'The accumulation of these gases in the atmosphere may cause heat from the sun to be trapped near the Earth’s surface – known as the ‘greenhouse effect’ '.

Greenhouse gases ‘may' cause heat to be trapped? No, we know with complete certainty that greenhouse gases cause heat to be retained in the atmosphere. And we have known this for a hundred years. Without the greenhouse effect the average Earth temperature would be about 33 degrees lower than it is today. No-one, literally no-one, denies this.

3, ‘Opinion on climate change is divided’

Actually, the research being discussed by ONS at this point shows that opinion on the effects of climate change is divided.

There is real and important debate on the impact of increased greenhouse gas concentrations on the world’s climate. But no uncertainty whatsoever exists as to the existence of the greenhouse effect. The ONS needs to get out more and talk to a few scientists.

Alstom gives hope that CCS will be financially viable

While policy-makers debate how to ensure the UK gets more low carbon electricity, the big generators are actually piling their capital into large numbers of new gas power stations. Future achievement of carbon reduction targets will therefore wholly depend on finding economical ways of capturing the CO2 coming out of gas turbines. Without carbon capture and storage (CCS) the current rush for gas will lock the UK into high carbon electricity output for another generation. We urgently need to include CCS in the current support schemes for low-carbon generation. Alstom, the world leader in CCS, has just released estimates suggesting that new plants with carbon capture should produce electricity at lower cost than any other low-carbon source. (1) Based on the results from 13 pilots and demonstration projects, the company is firmly optimistic about the main CCS technologies, saying that ‘technology and costs are not in themselves obstacles to CCS deployment’. It talks of costs of around €70 a megawatt hour, a far lower figure than nuclear energy is likely to cost. Its confidence contrasts with the wariness of the Committee on Climate Change which recently described the economics of CCS as ‘highly uncertain’. The CCC is probably being appropriately cautious, but the no-one is going to find out unless major countries commit to real support for CCS demonstration projects. The signs are not auspicious: the world’s most important pilot at AEP’s Mountaineer coal power station was abandoned a few weeks ago because the US government’s lack of any form carbon policy made investment impossible. Even if CCS only adds a small amount of the cost of generating electricity – and it will always do so – no generator will spend the money without a clear set of financial incentives that reward it for capturing and storing the CO2.

Similarly, to say that the UK administration has dithered on CCS would be unfairly sympathetic. In May 2007, BP’s advanced plans to build a plant to capture the CO2 from a plant on the north east coast of Scotland were scrapped because of the UK government’s refusal to let gas power stations participate in the CCS competition it planted to launch in 2007. Now, four years later, the CCS competition appears to be stalled. Those watching the disarray ruefully comment that if BP had been given the go-ahead, the UK would now be close to having the first fully functioning low carbon fossil plant sending CO2 into a depleted oil field. Instead we have got little but windy rhetoric.

Alstom’s confidence should force us take note. If the company is right – and it has more experience than anybody else in the world – CCS will be by far the best way of decarbonising electricity generation. Without any equivocation, the company says that a gas power station capturing and storing its CO2 will be competitive with a conventional power station at a carbon price of no more than €40 a tonne. Nuclear power will need financial support equivalent to at least twice this figure.

Like nuclear, a gas power station equipped with CCS will be able to operate round the clock, with no worries about unpredictability or intermittency. Alstom suggests that the greatest uncertainty lies not in the engineering of carbon capture, but in the lack of firm knowledge of how much it will cost to run CO2 pipelines and inject the gas into depleted oil reservoirs or into the deep saline aquifers underneath our feet. (Much of northern Europe sits on top of an aquifer that looks suitable to accept CO2). But, however uncertain, these costs are less critical to the financial viability of CCS than the capital and operating cost consequences of initially capturing the carbon

To my mind, the other possible advantage of CCS is that it requires the continued consumption of fossil fuels, helping to keep the price of coal and gas high. CCS plants actually need to use more fossil energy to generate electricity than a conventional plant, increasing the rate of depletion of cheap sources of coal and gas and increasing the incentive to switch to low carbon alternatives.

But, in any event, the UK urgently needs to include CCS in its renewable energy subsidy scheme (ROCs) to provide an immediate and transparent incentive. If the incremental cost of CCS is as low as Alstom claims, the generators now quietly building tens of gigawatts of new natural gas plants around the UK will need less than half the subsidy of offshore wind to incentivise them add CCS. Why not try it and see what happens? It can’t be any worse than the mess that CCS policy is in at the moment.

(1)    Cost assessment of fossil fuel plants equipped with CCS under typical scenarios, Jean-Francois Leandri et al.

The case that biodiversity has substantial economic value is not yet made

Mark Lynas’s wonderful new book ‘The God Species’ attempts to put environmentalism back on track. Humankind, he says, will only be able to keep within natural boundaries by using science and technology to help minimise our growing impact on the planet. He looks at nine specific environmental indicators - the atmospheric concentration of CO2 is the best known – and offers a view of how close we are to the safe limit. One of these indicators is the loss of biodiversity.Humankind is presiding over an astonishingly rapid extinction of species and Lynas says that this loss ‘arguably forms humanity’s most urgent and critical environmental challenge’. He suggests that the rate of extinction is possibly two orders of magnitude greater than the world’s eco-systems can sustain. Put at its simplest, the justification for the concern over biodiversity loss (of which extinction is merely one facet, of course) is that species variety helps maintain stable natural environments. Extinguish all the predators and the prey can become dangerously dominant. Cultivate just one crop and nutrient loss into watercourses is far worse than if many types of plant are grown. But just how strong is the evidence that biodiversity loss is economically damaging? If we cannot show a financial calculation our chance of getting policy-makers to take the issue seriously is close to zero.

Many reasonable people bemoan the current mass extinction but don’t understand why Lynas and the ‘planetary boundaries’ group of scientists think it is so disastrous. What really suffered, they ask, after the last wolves were hunted to extinction in England in the early nineteenth century? Sheep could be more safely grazed and food production increased. Is there really a strong case that biodiversity is worth more than the economic benefits of reducing pests and predators? I think we are all very willing to be convinced that biodiversity is crucial but, to be frank, the evidence may not yet be powerful enough.

A new paper puts some interesting numbers into the debate.(1) It looks at whether the degree of diversity in land use in the agricultural heartlands of the United States affects the risk of severe crop damage from insects. The theory is this: in agricultural monocultures, insects can breed without predators whereas a mixed landscape, with woodland and multiple crops, provides the living space for birds and bats that can help control any infestations.  So Timothy Meehan and his colleagues asked the obvious question: do diverse landscapes result in farmers having to use less insecticide? Assuming that farmers respond rationally to the beginnings of insect damage and spray the crops that are affected, the number of hectares receiving insecticide is a reasonable proxy for the threat from insects.

As we might expect, Meehan shows that diverse landscapes result in less insecticide use. In other words, biodiversity has direct economic value because spraying a crop costs money and time. What the research team calls ‘landscape simplification’ increases the likelihood that any particular hectare has to be sprayed. In what seems to me to be a heroic calculation, the scientists suggest that 1.4m more hectares need to receive insecticide each year as a result of the extensive use of monocultures of wheat, soya and maize across the Midwestern states. But the direct cost per hectare is assessed at only about $48. Compare this figure with, for example, the average yield of 20 tonnes of corn a hectare in good fields in Wisconsin, valued today (July 2011) at over $6,000. Put crudely, the value of the crop is more than two orders of magnitude more than the increased cost of insecticide on an affected hectare. And, equally powerfully, the research shows that only about 4% of total cropland needs insecticide application as a result of locally low levels of plant biodiversity. (Some crops will need pesticide protection even in the most diverse landscapes).

The lesson from the paper is therefore a simple one. In the specific case of the Midwest, landscape simplification is tending to push up insecticide use but the direct economic cost of this is trivial compared to the value of the crops. If the whole of this vast area were given over to a single crop, and every hectare had to be sprayed every year, farmers would still not be losing financially from the loss of biodiversity.

The response is to say that the costs to the farmer are only a small fraction of the total impact on society, now and in the future. High levels of pesticide use mean poorer water quality and air pollution, possibly affecting the health of people hundreds of miles away. Heavy insecticide use will eventually cause pest mutations that will require a new generation of chemicals. Applications of insecticide may cause the deaths of beneficial soil organisms. Nevertheless, Meehan’s paper does not immediately provide support for Mark Lynas’s conclusion that biodiversity loss is potentially the worst environmental problem the world faces.

Timothy Meehan et al., Agricultural landscape simplification and insecticide use in the Midwestern United States, PNAS (OPEN ACCESS) July 2011.

Scottish wave power marches on

The last weeks have seen some crucial developments in the commercialisation of wave power. Inverness-based AWS received major investment from Alstom, the French power generation company. Aquamarine Power of Edinburgh, backed by Scottish and Southern, started drilling the foundations for the second major trial of its Oyster wave energy collector in the Orkneys. The machine itself is being finished at Burntisland Fabrications and will be installed over the summer. The granddaddy of them all, Pelamis, took on a round of new money from investors and continued its plans for installing its huge red sea-snake-like devices for E.ON and Scottish Power. As well as having tidal currents that match anywhere in the world, the UK has excellent potential for using waves to generate electricity. Despite this, the National Grid’s seven year forecast sees no wave farms before at least 2018. Other commentators, such as the Committee on Climate Change are politely unenthusiastic.

Who is right, the hard-headed financial analysts or the committed companies pushing ahead to install wave collectors in the waters off western Scotland and the northern isles? My money would be on the bloody-minded enthusiasts pushing ahead with their huge steel structures in the face of mild scepticism from banks and governments. I spoke to Martin McAdam, the CEO of Aquamarine Power, to discuss the opportunities for wave power in the UK and understand what needs to happen to get rapid growth in wave power utilisation.

There is, of course, nothing new in observers being sceptical about a new technology while the inventors and engineers running the business developing the machines are mustard keen on the opportunities. Wave is no different to so many compelling opportunities in the past. It is currently four or five times too expensive to compete with gas for electricity generation, even on the west coast of the British Isles. The engineers still have major technical challenges to overcome.

The power of the waves

Waves a few hundred metres from the shore can contain huge densities of energy, often as much as tens of kilowatts per linear metre. The ordinary British house, using about half a kilowatt on average across the 24 hour day, could be powered by a device collecting the energy in a few centimetres of waves. There is a downside to the density of energy in a wave – most collectors that have been tried off the shores of the UK have failed within a few days, unable to deal with enormous forces being placed upon them. Since the Edinburgh-based engineer Stephen Salter developed his eponymous ‘Duck’ in the 1970’s, hundreds of companies have tried and failed to convert wave energy into commercially-priced electricity. It is only in the last few years that credible designs have been developed that are both efficient at capturing wave motion and which can hope to survive storm conditions.

Aquamarine Power's Oyster is one such device. A large scale prototype worked successfully at the Orkney Wave Centre for the best part of a year. A scaled-up device generating a maximum of 800 kilowatts is will be installed at Billia Croo in the Orkneys in late July with the first commercial machines put in place in 2014.

How does it work? ‘It has a design like a laptop’, says Martin McAdam, ‘with the lid, mostly submerged, moving back and forward with the waves’. This motion powers pumps which generate high pressure water. A pipe takes this water to the shore, where it drives conventional hydro-electric turbines, housed in containers. The crucial part of the design is that most of the critical equipment is on-shore, easily and conveniently maintained without having to get into a boat in rough seas. A relatively small number of moving parts are offshore. The design used by the Oyster is very different to the other contenders, with Pelamis capturing the energy from the flexing of the joints in its thin body and AWS getting power from the bobbing of the waves changing water pressure inside the twelve-sided floating structure.

McAdam says that the ideal location is in water about 15 metres deep. Around much of the UK, this depth can be found quite close to the shoreline, with the new site in the Orkneys about 500 metres from land. He says that the Oyster technology installed in large farms in appropriate locations around the British Isles has the potential to generate a maximum of about 8 gigawatts, with the other obvious European markets, such as Portugal, Ireland and France, offering another 8 gigawatts of potential. (For comparison, current total UK generating capacity is about 75 gigawatts, with average demand running at about 35 gigawatts). Oyster’s parent, Aquamarine Power, has its eyes on sites for a 200 megawatt farm in Orkney and 40 megawatt installation off Lewis in the Western Isles. What about expected rates of actual production, as opposed to peak power? McAdam mentions an expected annual output of about 35-40% of the maximum capacity, comparable to well-sited offshore wind turbines. In quiet years, such as 2010, this number would be lower.

The estimates from Aquamarine’s CEO are not inconsistent with the Committee on Climate Change’s figure of 40 terawatt hours for the potential for wave power, about 12% of current UK electricity usage. However McAdam stresses that other companies’ machines will work in locations not suitable for Oysters, implying that the total UK potential may be substantially greater than the CCC thinks.

Wave power is intermittent but marine energy has two advantages over wind. First, it is rarely, if ever, completely still on the western coastline of the UK. Unlike wind turbines, which require a reasonable breeze to start turning, wave collectors will almost always generate some power. Second, wave energy tends to be out of phase with wind power. If it is blowing a gale today, the waves, generated a long way away and only gradually reaching the shore, will arrive after the wind has blown itself out.

Martin McAdam gives some figures for the cost of his collectors. The first Oyster installed in the water cost about £35m per megawatt of peak capacity. The machine being attached to the seafloor over this summer costs about £10m per megawatt. McAdam sees the figure declining to about £3m once costs have been driven out by further R+D, ‘learning by doing’ in the fabrication process and from the benefits of installing many devices along the same piece of shoreline. At £3m, wave is competitive with today’s offshore wind costs, which are running at about £4m per megawatt in shallow locations. Since ‘capacity factors’ are similar at about 35-40%, the output per megawatt installed will be about the same as a wind turbine and the costs of megawatt hour very similar.

Wave farms face many of the same technical challenges as offshore wind. The brutal environment means wave collectors need to be made from huge quantities of corrosion resistant steel. Fabrication is not a simple matter – the leading UK constructor, Burntisland Fabrications or BiFab, is going to be very busy indeed. Wave farms will tend to be far away from easy connection to robust parts of the electricity distribution network. Maintenance work on wave collectors will be difficult, and the absence of electrical gear on the Oyster itself is a huge potential advantage compared to some other offshore technologies. Similarly, the relatively shallow depth in which the Oyster machines operate – 15 metres – implies that, according to the laws of wave physics, all waves greater than 15 metres will have broken by the time they pass over the device, improving survivability.

The crucial question facing the wave power industry is how to get from about £10m per megawatt to £3m as fast as possible. McAdam says while private money and the grants from government bodies such as the Carbon Trust have been very useful these funds are going to be enough to push wave to a point at which it is viable without subsidy. For rapid rollout of wave power, the industry needs a substantial injection of subsidy for further R+D and cheap equity to enable the construction of substantial farms of collectors. This will enable the industry to move down the learning curve far faster than would otherwise happen.

Sceptical commentators will note that unproven renewable technologies often demand large subsidies in order to reach commercial viability at some uncertain and always receding future date. And, indeed, much money on energy R+D will be wasted. Marine Current Turbines in Bristol is close to proving that tidal current power can overcome technical challenges but no company in the wave business can yet claim similar certainty. Real issues remain and waves may never produce power that is cost-competitive with other low-carbon technologies. Nevertheless, consider the following comment in a letter published by distinguished scientists in the Guardian on 13th October 2010, commenting on the £2bn a year spent on military research.

‘As an example of the current imbalance in resources, we note that the current MoD R&D budget is more than 20 times larger than public funding for R&D on renewable energy.’

McAdam says his company might only need to make a total of as few as 50 or 60 Oysters to get the costs down to the £3m/MW figure. If subsidy on all these first production machines was £7m a megawatt, the total public cost would  be about £400m, a massive amount but neglible in terms of the amount spent on military research.

Wave power collectors could provide one of the UK’s most important manufacturing exports in twenty years time. The natural energy resources around Britain’s coast may eventually provide a substantial fraction of our energy needs at almost zero running cost. Does it not make sense to divert a larger fraction of the government’s R+D budget towards this increasingly plausible form of low-carbon, environmentally relatively benign, electric power?

Your chance to tell Mark Lynas where the green movement needs to go from here

Here are a few comments from Mark Lynas, quoted in a Guardian article yesterday (14th June). '...the green movement is stuck in a rut, but I think the problem is deeper than mere professionalisation and endless strategy meetings in corporate NGO head offices.

"Many 'green' campaigns, like those against nuclear power and GM crops, are not actually scientifically defensible, whilst real issues like nitrogen pollution and land use go ignored. The movement is also stuck in a left-wing box of narrow partisan politics, and needs to appeal to a broader mass of the public who are simply not interested in organic farming and hippy lifestyle choices. It needs to re-engage with science, as well as with the general public, if it is to remain relevant to the 21st century'.

Mark's new book The God Species, available in shops in the next few weeks, looks at what the world's environmental movement needs to focus on. How can we use science productively to solve ecological problems? Along the way, he takes multiple swipes at what he sees as the irrational and anti-scientific tendencies in many green organisations, obsessed with fighting the wrong battles.

Come to listen to Mark Lynas and Professor Johan Rockstrom, the leading figure in the 'planetary boundaries' movement that seeks to quantify the ecological limits that mankind has to stay within. Central London, afternoon Wednesday 6th July, free admission but reservation vital. All the details are here.

(22.June.2011 - last few tickets available, book now)

Planetary Boundaries PDF

(When booking, please say you saw these details on Carbon Commentary).

Much more UK wind power by 2018 than previously forecast: National Grid

  Every year the National Grid produces a statement that identifies how much UK electricity generating capacity is expected to open and to close over the next seven years. The Grid is careful to say that its ‘Seven Year Statement’ is not intended to be used as a forecast but this vital document gives clear indications of how it thinks the demand for electricity will be met over the next few years. The most recent statement, published at the end of May 2011, suggests that the Grid is becoming far more bullish about wind power – particularly offshore - and about new gas power stations.

Last year, it suggested that about 8 gigawatts of wind capacity might be constructed between this year and 2016. The number has risen to 15.5 gigawatts in this year’s review. Projected new gas plants are up from 12 GW to 13 GW. Unsurprisingly, the Grid has pushed back the date of the first new nuclear stations to 2018.

The recent review of renewable energy potential by the Committee on Climate Change estimated that the UK would have installed 28 GW of wind power by 2020. It sees slightly more onshore wind by this date (15 GW) than offshore (13 GW). The Grid’s view is very different, with a projected 18 GW offshore by 2018 and only 8 GW onshore, with very high rates of installation in offshore waters possible beyond 2015.

This is how the National Grid sees UK generating capacity in 2018.

Generating technology	Amount of potential capacity (gigawatts) in 2018
Gas (CCGT)	45, (29 today)
Coal	21, (29)
Offshore wind	18, (1)
Onshore wind	8 (2)
Nuclear	13 (11)
Other	9 (10)
TOTAL	114 (82)

The increase in total generating capacity is, of course, partly a mirage since wind power only generates about 30-35% of its maximum power, with offshore at the higher end of the range. But the National Grid is seeing nevertheless a remarkable switch towards offshore wind, a point that commentators seem not to have picked up.  By 2018, if these numbers are accurate, the UK will be getting something over 20% of its electricity from wind, or average of 8-9 GW, compared to no more than 1 GW at the moment.

On the negative side, National Grid is seeing a very limited investment in grid connected tidal power, with only about 0.1 GW connected by 2018. It postulates over 2 GW of biomass power stations, meaning that even including today’s hydro-electric plants, renewables other than wind will be little more than 3 GW. The Climate Change Committee’s scenario for 2020 has a much large figure of about 10 GW, implying far more optimism about the prospects for biomass, tidal and wave.

We might see measurable amounts of solar PV by 2018 in terms of capacity, but the typical installation will perform at only about 10% of its rated power, meaning that even if 2m homes sign up to feed in tariffs the UK will struggle to get an average of 0.5 GW of power from the sun. The 2018 scenario sees 2 nuclear power stations completed during 2017/8 at Wylfa and Hinckley Point.

As an aside, National Grid forecasts show large amounts of spare electricity generating capacity as some of the coal-fired stations close in the 2015 and 2016 period. The generators are falling over themselves to install gas plants, with the winter peak maximum demand of about 60 GW almost covered by nuclear stations and by gas plants alone, with no need for any contribution from coal power at all, even from the power stations remaining open. The lights will not go out.

'Ten Technologies' is one of the five best books on climate change

TheBrowser.com asked the writer, editor and campaigner Duncan Clark to recommend the five best books on climate change. He nominated 'Ten Technologies to Save the Planet', the US edition of my 2009 book. http://thebrowser.com/interviews/duncan-clark-on-climate-change

Many thanks to Duncan. He may or may not want it to be known that he had a hand in commissioning and editing three of these five books, including mine. All of the authors will share my deep gratitude for Duncan's help and support.

Tidal energy - the UK's best kept secret

The latest report on Renewables from the Committee on Climate Change (CCC) offers lukewarm support for electricity generation from tidal streams. The UK has some of the fiercest tidal currents in the world, but the CCC says the tidal turbines will deliver energy at a higher cost than PV in 2040. The assumptions behind this pessimism are questioned in this note. The tides around Britain’s coasts sweep huge volumes of water back and forth at substantial speeds. The energy contained in the tidal races off the west of the UK is as great as anywhere in the world. Because water is a thousand or so times heavier than air, the maximum speeds of perhaps 6 metres a second are capable of generating far more electricity per square metre of turbine area than a windmill. The Pentland Firth, the narrow run of water between the north-east tip of Scotland and the Orkney islands, is possibly the best place in the world to turn racing tides into electricity. The challenges are immense: massive steel structures need to be made that survive huge stresses, day after day.

The rewards for tidal stream developers are commensurate. Unlike other renewable technologies, tidal power is utterly predictable for the entire life of a turbine. We know to the minute when the tides on a particular day will be at their peak. Once installed, the running costs of tidal stream technology will be low. The environmental impact of tidal turbines appears to be very small. And the UK could probably provide a quarter of its electricity from tides. (And much more if an environmentally acceptable means was found of damming the Severn tides).

The CCC might then have been expected to push for a significant programme of support for tidal. Its reservations appear to be as follows.

a)      Tidal generation does not help with the ‘intermittency’ problem of renewables generation.

b)      The levels of yield are relatively low. (Yield is the percentage of rated power that can be delivered in a typical day.)

c)       The cost of capital is high for a developer using tidal turbines because of the risk of the technology not working

d)      The relatively small scope for learning curve improvements.

Intermittency

An individual tidal turbine will generate most electricity when the tide is running fastest. This will be at approximately the mid point between high and low tides. The CCC therefore says that tidal power will not help deal with periods of low production.

The problem is expressed here in Chart 1.4 of the CCC’s report.

The cycle of marine power (tidal plus wave) suggests that total output will fall to zero four times a day. This would only be the case if all the turbines were sited at the same place. Turbines placed, as they will be, all around the coasts of Great Britain will generate maximum power at different times of the day. On the day I looked at the tide tables, the tides in the Channel Islands (where there are some extremely powerful races) were completely unsynchronised with the tides in northern Scotland. Two turbines, one off Alderney, one off John O’Groats, would together produce substantial amounts of (entirely predictable) power every second of the day. Tidal power is as dispatchable as nuclear.

Yields are low

The CCC offers a view as to the output of a tidal turbine, suggesting that in a ‘high’ case the figure will be 40%. That is, the average electricity output of a 1MW turbine over the course of a year will be 400kW.

Actually, the one piece of reliable data on this number suggests a much higher figure. The UK’s hugely impressive tidal turbine developer, Marine Current Turbines (MCT), has had a device in the waters of Strangford Lough for several years. This early turbine has produced 50% of its rated power. The difference is important: it means that electricity generation costs are 25% lower than the CCC would otherwise have predicted.

The cost of capital is high

I think the CCC – normally so forensically rigorous – makes an error here, guided by its capital markets advisors Oxera. The CCC suggests that capital projects have to earn a return determined by the ‘riskiness’ of the investment. The debate over what types of ‘risk’ need to be paid for is complex and almost theological in its intensity. But I will not argue about this and will accept that early tidal power projects are ‘risky’ and that investors will therefore expect high returns to compensate for their exposure.

But let’s dissect what the ‘risk’ of a tidal project actually is. At its simplest, it is that the technology will fail. And, indeed, most tidal turbines have simply broken into pieces in the early months of their life in the seas. But this is the only risk. Once working successfully, the tidal currents will flow for as long as the moon circles the earth. There are no commodities markets to disrupt the returns, no risk of increased operating costs once the technology is proven. To say that tidal has a high cost of capital is wrong: the early developers take big risks but once the technology matures, the operating risk disappears. The right assumption to make about tidal is that has huge cost of capital today, but will have very low rates in the future once the technology is proven. Instead, the CCC’s advisers weight tidal down with high returns on capital for ever. This unfairly penalises tidal stream power, and all other sources of energy in their early stages of development.

Small scope for learning curve improvements

Other renewable technologies have generally reduced in underlying cost by 10 or 15% for every doubling of the output of these devices. (This is an utterly standard ‘experience’ effect- we’ll assume tidal turbine costs only fall by 10% for each doubling).

To date, the world tidal industry has probably installed less than 20 full-scale production devices on the seabed. In fact, you could plausibly say that the MCT Northern Irish turbine is the only such turbine. Assume nevertheless that today’s accumulated production experience is 20 units.

But the CCC, advised in this case by Mott McDonald, says that costs today are about 20.5 pence per kilowatt hour of electricity generated and will only fall to 15.25 pence in 2040, a reduction of slightly more than 25%. (1) The learning curve model assumes that a 10% reduction will typically come after a doubling of total production to 40 units. A further 10% reduction comes when accumulated volume rises to 80.

The arithmetic is not complex. If Mott McDonald thinks that the costs will only fall to 15.25, it must believe that the worldwide tidal industry will install less than 160 turbines before 2040.

The CCC’s analysis locks tidal stream technology into relative failure. Costs are high, and the technology risk is great. So no developers use the tidal turbines and costs remain stubbornly high. The cycle continues. Of course this could indeed be the future. But with sustained effort and support, tidal energy may become of the UK’s most important industries. In MCT – a business few people have ever heard of - the country has the most technically advanced marine energy company in the world. I think it deserves all the backing it can get.

(1,) The mid point of the cost ranges in Figure 1.10 of the CCC’s Renewables report. All numbers in real money.

Hydrogen: the numbers still don’t stack up (and probably never will).

The dream of the hydrogen economy persists. Proponents say that hydrogen, potentially one of the densest energy sources available to us, can provide our transport fuels and the energy needed in the home. But progress has been far slower than expected over the last few decades so I visited two leading UK innovators to try to understand why. ITM Power in Sheffield makes a mobile electrolyser that can make hydrogen by splitting water into its two constituent elements. The business sees hydrogen replacing petrol in cars, either by using fuel cells to create electricity to drive a motor or by burning the hydrogen in an engine. AFC Energy, a company based in Surrey, produces low cost fuel cells that use hydrogen and the oxygen in the air to generate electricity. Its partners include the supermarket chain Waitrose, which is interested in using fuel cells to make the electricity for shops.

 Both companies have excellent technology and first-rate manufacturing skills. But if I understood the economics of their products correctly, I believe neither can hope to compete with other sources of energy, except in a few very unusual circumstances. The problem is that making hydrogen will always use energy, and that energy could always be more productively used instead to directly generate electricity in a higher efficiency process.

Let’s consider ITM Power’s proposition first. ITM uses electricity to split water into hydrogen and oxygen. Its electrolysis (separation of water into its constituent elements) is about 70% efficient. That is to say, it uses 10 units of energy to break the chemical bonds between the atoms of hydrogen and oxygen compared to a maximum of 7 units of energy, either in the form of heat or electricity, gained by then recombining the two gases to make water. This maximum of 7 units can never be actually achieved. Hydrogen burnt in a car engine (yes, petrol/gasoline engines can be modified to use H2 as a fuel) might generate about 2 units of useful energy. The rest is lost as heat. Hydrogen pumped into a fuel cell, which then generates electricity, can push this figure up to about 4 units. The implications of these numbers are simple. Use 10 units of electricity to split water, store the hydrogen and then use it later to convert back into electricity and you get only 4 units back.

Compare this to other means of storing electricity: use cheap power to pump water uphill and then releasing it through turbines is about 70% efficient (electricity out compared to electricity in). Modern batteries work at about 80% and newer technologies like compressed air storage (use the power to compress air, then release it through turbines) can eventually hope to achieve similar levels of success.

This wouldn’t necessarily be the end of the story if the equipment needed to make hydrogen was inexpensive. At times when electricity is very cheap, such as on windy summer nights when demand is low, hydrogen could be used to store electricity for sale at peak prices the following day. However ITM Power quote a cost of about £700,000 for its extremely impressive H2 manufacturing and storage system, housed in two standard freight containers. This unit will generate about 2 kilogrammes of H2 an hour, with an approximate energy value of about 80 kilowatt hours. At best, the system might hope to store energy for twelve hours a day, spending the rest of the time creating and selling electricity. Each day the kit might therefore store about a megawatt hour of electricity, buying power for part of the day, and selling the megawatt hour at peak times.

Compare this to a large rack of batteries with a similar capacity. A 2010 Deutsche Bank study (1) suggested that current prices from lithium-ion batteries are about $450 per kilowatt hour, or $450,000 (less than £300,000) per megawatt hour. This figure was for automotive use – larger scale industrial power storage units should be a bit cheaper. So battery storage – which operates at 80% efficiency is less than half the price of hydrogen storage, which has a typical output-input ratio of 40% today.

The unfortunate truth is that hydrogen is a poor way of storing electricity and the differences between H2 and batteries will probably widen because of the huge amounts of cost-reducing R+D going into lithium-ion batteries. I’m sure ITM Power knows this. It has focused instead on serving the vehicle fuel market. The rise in the price of oil means that mobile power is much more expensive than stationery energy. A UK household pays 12 or 13 pence per kilowatt hour for electricity and slightly more than this for petrol. (For US readers, the price of petrol (gasoline) in the UK is about $2.20 per litre or over $8 a US gallon). But a standard car gets only about 3 units of useful work for each 10 units of energy put in the tank with the rest lost as heat. However if we power a car with electric motor, this ratio is about 8 to 10, better than twice as good. It really makes sense to drive an electric car.

However the sad fact is that this doesn’t mean we should use hydrogen to make that electricity. (In a fuel cell car the hydrogen pumped into the tank generates electricity which then turns an electric motor). Remember the crucial calculation above – if we make hydrogen using electricity and then use it to regenerate electricity in a fuel cell, we get 4 kilowatt hours out for every 10 we put in. But if we just take electricity and store it in battery in the car we get 8 units out for every 10 we put in. And, crucially, the batteries are far cheaper than the fuel cell. A fuel cell car using hydrogen will cost more and deliver half the number of miles of travel for each unit of energy employed when compared to a battery car. The implication is that hydrogen isn’t very useful as a mobile power source.

Thus far we’ve looked at the value of using hydrogen as a way of storing electricity and as a way of moving a car. What about the third opportunity, as a means of generating stationary power? This is where AFC Energy’s technology comes in. AFC’s low cost fuel cells, using clever catalysts and cheap materials, can take hydrogen and generate electricity for shops, factories or office buildings. The problem is making the hydrogen in the first place. Certainly it is true that some industrial processes have hydrogen as a by-product. This hydrogen will generally then used for the manufacture of ammonia for fertiliser, but it could instead be inserted into a fuel cell to make electricity. AFC Energy have a prototype fuel cell going into a plant making chlorine in Germany with abundant supplies of waste hydrogen. I haven’t done the sums necessary to work out whether the hydrogen would be worth more as an input to fertiliser manufacture than for making electricity but I suspect the latter is more valuable. However the worldwide chlorine manufacturing sector will only generate enough hydrogen, AFC Energy says, to provide about 3 gigawatts of continuous energy. This is the equivalent of two very large power stations.

But for most of the potential applications of AFC’s beautifully designed technology, there won’t be cheap hydrogen available. It will have to be made on-site. Making H2 using electrolysis, and thus using electricity, in order to run a fuel cell to then generate electricity is clearly wasteful. We’d get about 4 units of electricity out for ever one we put in. AFC believes the alternative should be steam reforming of natural gas, which is largely methane (CH4). High temperature steam and a catalyst will split methane into hydrogen and carbon monoxide/dioxide. This is a well understood technology.

Think for a second about what is really going on here. Natural gas is being split at the fuel cell site, with a high energy cost. The hydrogen produced is then fed into a fuel cell, which will get about 6 units of electricity for every 10 units of hydrogen energy used. The overall efficiency will – once again - be about 4 units of electricity out for every 10 units of energy in. Compare this to a conventional modern gas-fired power station, which burns methane and uses some of the waste heat for a second turbine cycle. This gives up to 60% efficiency. Some electricity, perhaps 6%, is lost in the transmission across the grid, meaning a total efficiency of somewhere above 50%. Unless I am missing something, it is therefore better to burn natural gas in a power station than to crack it using steam and then use the resulting hydrogen in a fuel cell. Importantly, the carbon emissions will also be lower from a modern gas plant because less methane is burnt to create the equivalent quantity of electricity.

AFC responds to this point by saying that a fuel cell gives the owner security of electricity supply. In some senses, this is true. If the power fails at a site, the fuel cell will continue to produce electricity, provided there is gas available. But other than temporary outages, the primary reason that power cuts might happen is a shortage of fuels for electricity generation. If there is gas available in the UK, then the large power stations will use it for electricity generation. If there isn’t natural gas, then neither the power stations nor the AFC fuel cell site will have it. The power from an AFC fuel cell will only be as secure as its natural gas supply.

The second argument AFC makes is that when the technology is mature local electricity generation by a steam reformer and an adjacent fuel cell will produce electricity at a price of 12p per kilowatt hour, only perhaps a third more than is currently being charged by electricity suppliers to large users. The numbers to support this assertion are not available. But it would be extremely surprising if the electricity were ever cheaper than standard generation. AFC quotes a cost of about £1.2m for a 180 kilowatt system. This means over £6,000 per kilowatt, compared to about £1,000 for an equivalent share of a new CCGT gas plant. Operating costs are also likely to be much higher than at a conventional power station. Lastly, a conventional gas plant will find it far easier to fit carbon capture and storage. These are the arguments against seeing hydrogen as a important source of cost savings or carbon reduction. Fuel cells may work in specific applications, such as where the waste heat can be used in a domestic home or where the high levels of nitrogen leaving the system are useful for reducing fire risk, such as in a datacentre. But as far as I can see the fundamental energy economics of creating H2, with the associated heat losses, and then using the gas either in a combustion engine or in a fuel cell (with a maximum of about 60% efficiency) must mean that hydrogen has a very limited role in the future low carbon world.

(With many thanks to the people at ITM Power and AFC Energy for their help. Errors are mine.)

(1) The DB report is available here: http://bioage.typepad.com/files/1223fm-05.pdf

More materialism please

Fashion and sustainability do not easily mix. As societies become richer, they tend to buy more clothing. Old clothes languishing at the back of the wardrobe are thrown out, usually ending up in landfill or dumped into used clothes markets in less prosperous countries. One study showed that the weight of textiles sold in the UK nearly doubled in the prosperous decade from 1998 to 2007. (1) In How to Live a Low-carbon Life, I estimate that the carbon footprint of clothing in the UK may be as much as a tonne per person per year, or not far short of 10% of the total, and this figure will rise alongside any increase in the future sales of clothing. Fashion exemplifies the difficulties of reconciling economic growth, which gives us all more money to buy clothes, with the need to reduce emissions. The essays in a fascinating new book, Shaping Sustainable Fashion, look in detail at the how our need to keep ourselves warm and looking good can be reconciled with reducing CO2, and also reducing the environmental impact of growing cotton, possibly the most ecologically damaging crop in the world. (2) As the concluding chapter notes, we will not solve the problem until we become truly materialistic. Fast fashion and cheap disposable clothing show that ‘we fail to invest deep or sacred meanings in material goods. Instead we simply have ‘an unbounded desire to acquire, followed by a throwaway mentality’, which is the opposite of real materialism.

The photograph at the top of this post is of an article of clothing worn by Edward for several decades and discussed in the profoundly thought-provoking essay by Kate Fletcher that concludes Shaping Sustainable Fashion. Here is what Edward says about this valued and stylish piece of clothing.

‘I call this my three stage jacket. It began about forty years ago as a very slim waistcoat that was given to me. I knitted a panel and put it in the back just to be able to fasten it together at the front, you see. And then about fifteen years ago I added sleeves and a collar and some trimmings. And then, only about five years ago, I became a bit too big to button it up so I added latchets across the front so that I can fasten it.’

This is true materialism. It values and celebrates the physical objects of our lives, maintaining and refreshing them as we pass through the world from birth to death. I suspect that this jacket is indelibly associated with Edward in the minds of his friends. Because it is largely made by him, it exhibits his manual skills to all he meets. It is part of him.

Of course we need to recycle more; only about 10,000 tonnes of the 2m tonnes of textiles bought a year in the UK is properly recycled by taking the clothing apart and reusing the fibres, representing about one half of one percent of total consumption. But even a massive growth in full recycling is not enough. The world has to find ways of divorcing  our understanding of ‘prosperity’ from the continued growth in the number of things we buy, consume, and then throw away. As Kate Fletcher suggests, people need to recast themselves, moving away from being just passive consumers, enslaved to Primark and Zara’s endless rotation of new items in shop windows,  to becoming ‘suppliers of ideas and skills to fashion’ so that they value and cherish the clothes that they own, caring for them for decades.

We will not solve the world’s multiple ecological problems by telling ourselves and other people to buy less. The importance of consumption is far too firmly ingrained into our modes of thought. No-one, for example, imagines that Catherine Middleton should wear an old dress for her wedding this week. However a truly materialistic society would be looking forward to seeing her wearing the outfit her mother and her grandmother wore as their wedding dress, updated and adapted so that it became hers, perhaps even by using a sewing machine she learnt to use at school. Her husband, mutatis mutandis, would do the same.

(1)    Maximising Reuse and Recycling of UK Clothing and Textiles, Oakdene Hollings for Defra, October 2009. Chart on page 11 shows a rise from an index of about 90 in 1998 to over 160 in 2007.

(2)    Alison Gwilt and Timo Rissanen, Shaping Sustainable Fashion: changing the way we make and use clothes, Earthscan 2011

How much of Japan’s land area would be needed to generate all its electricity from wind?

  The opponents of nuclear energy claim that Japan could produce much of its electricity from wind. (See the debate at Climate Progress). Others, such as the Breakthrough Institute , offers estimates of how of the country's land area would have to be covered with turbines to generate enough electricity. Below is my estimate of how much of the country would be required – about 10%. Since Japan gets about one quarter of its electricity from nuclear power about 2.5% of the land area would need to provide the equivalent amount of power. This would come from about 50,000 turbines.

My producution figures are almost certainly far too low. I use a high estimate of the average number of watts of electricity produced per square metre of land and my figures assume constant hourly production. But of course wind is highly erratic, so far more wind turbines would have to be installed to meet the total need. The actual production of onshore turbines - which are generally less productive than offshore wind farms - would probably be much less than 3 watts per square metre. Japan would also need extensive grid links with other Asian countries to protect against long periods of low wind speed by giving the country to import large quantities of electricity. Unlike Britain, Japan does not have a single electricity network. This would further enhance the problems of dealing with regional shortages and surpluses of wind power.

I’d be very grateful for any corrections to these numbers.One point for clarification. The figures I give are for typical production of working turbines, properly spaced over large areas so that one turbine does not steal the wind of another. Pack the turbines more closely and you might get higher total production, but at much higher cost. Wind farms really do need lots and lots of space. The world’s biggest offshore installation, the planned London Array, will need over 230 square kilometres to provide 1000 megawatts of maximum generating capacity. Some turbines will be spaced over a kilometre apart.

Wind                                             a 3 watts (1) per sq metre                                         b 3 megawatts per sq kilometre                                         Japan                                             c 377,835 sq kilometres                                                                     Total wind production if all of onshore Japan given over to turbines                                     d 1,133,505 megawatts production if all of Japan used                for wind farms (2)               e 8,760 hours per year                                         f 9,929,503,800 megawatt hours per year                                         g 1,000,000 terawatt hours per megawatt hour                                       h 9,930 terawatt hours per year                                                                   Share of Japanese land area needed                                         i 1,075 terawatt hours per year used in Japan (3)                                     j 10.8% share land area of Japan needed                                        

 Notes

 (1)                         This figure is achieved by the best UK offshore wind farms        (2)         The land area multiplied by the electricity production per sq.m.    (3)                         Estimates of this figure vary slightly