We can all be glad that the Committee on Climate Change recommends zero emissions in the UK in 2050. Equally, we should welcome the assessment that the cost of this policy is low, at perhaps 1-2% of GDP in their estimates.

However a detailed reading of this long report raises some serious questions about the feasibility of the route that the CCC intends UK policy to follow. Put simply, we should have three main areas of concern:

Faith in technologies that are either untried or have already been shown to be uncompetitive

· The CCC has always had faith in the viability of Carbon Capture and Storage (CCS). In the latest report, CCS is used to capture up to 175 million tonnes of CO2 a year and sequester this safely underground in 2050. This is equivalent to about a third of the UK’s current emissions. Nobody questions that CCS is technically possible, but nowhere in the world is this amount of CO2 currently captured and stored, let alone sequestered. The CCC’s latest report looks at many new methods of carbon reduction, such as the use of electrolysis to manufacture hydrogen, and dismisses them as ‘speculative’. However it never questions the potential scale and low cost of CCS in the UK. This is despite the acutely painful experience around the world of fitting carbon capture equipment to new or existing power plants. Without CCS, as the report quietly points out, ‘hard to decarbonise’ sectors, such as aviation will continue to ensure the UK has emissions of around 3 tonnes per person per year, not the ‘net zero’ that the CCC suggests. The magic of CCS is used to wash away the high level of the UK’s remaining emissions.

· Similarly, the Committee continues with its extraordinary belief in the value of electric heat pumps as a means of decarbonising domestic heating, a very important source of current emissions. Once again, this faith is contradicted by experience; UK housing is simply too badly insulated to allow widespread heat pump use. Subsidies for air source heat pumps have been promoted for perhaps ten years in the UK, but takeup has been dismal. The reason, as perhaps the CCC should know, is that installations have often left householders cold and facing far higher energy costs than older gas boilers. The CCC’s faith in heat pumps sometimes appears almost theological, but is backed by negligible real world evidence.

· Not surprisingly, the CCC also continues with its assumption that new nuclear power will come down sharply in cost and will provide a substantial portion of the UK’s power. I don’t think any further comment is needed.

· Similarly, despite the growing evidence around the world of the cost-competiveness of renewable hydrogen, the CCC stays with its favoured solution of partially switching to hydrogen but making it from natural gas, with the all the emissions implications. (The assumption is that these emissions are all captured and sequestered).

Failure to deal with some of the major questions surrounding the energy transition

· Let me briefly list some of the things that are either not mentioned in the new report or are glossed over in a sentence.

o Dealing with large scale and frequent electricity surpluses as the UK invests more in renewable technologies, particularly offshore wind. Even today, we are seeing renewables and nuclear filling almost all UK demand. As offshore wind grows, these surpluses will get larger and increasingly frequent. There isn’t a word about this.

o Batteries are dismissed. There’s casual mention of home storage but nothing about large scale grid battery farms.

o Onshore wind, the UK’s cheapest energy source, plays no role in the 2050 projection. This is the CCC avoiding political controversy rather than carrying out its core task. (Don’t believe me? Look at Table 7.2 where the costs of key technologies are tabulated. Onshore wind isn’t there).

o Similarly, little is said about the crucial importance of home insulation in reducing emissions. The unpalatable truth is that most homes with cavity walls are now insulated and the major problem that remains is the 30% of homes with single solid walls. These are expensive and difficult to insulate but the CCC’s work makes negligible mention of this problem. This is despite the failure of previous government programmes to make more than a dent in the number of uninsulated houses.

· New technologies, such as direct air capture of CO2, are crudely dismissed as unproven. There’s a good point here; full decarbonisation is going to require some techniques that don’t exist today at anywhere near cost competitiveness. But when the CCC chooses to question the viability of these new approaches it should use decent, up-to-date research. Direct air capture, which the report writes of as costing £300 per tonne of CO2 in 2050, is already being achieved at prices well below this level. Top flight academic research gives figures below $100 in the next few years. This has always been a serious problem with the CCC’s work; it chooses to avoid keeping up with recent trends in technology, perhaps for fear of looking like a naïve enthusiast for half-baked carbon reduction schemes. Scepticism is fine, but ignoring the proven potential for new technologies is not.

· It’s part of my particular set of prejudices that the future world will make massive quantities of cheap electricity and use temporary surpluses (such as when an Atlantic gale is blowing) to provide the energy to make synthetic fuels cheaply. These zero net carbon fuels, such as replacement kerosene, can then be burnt in aviation or other tough-to-decarbonise activities. Other countries around the world are working on this today but the CCC sniffs and says research in the UK ‘should not be a priority’. Never miss an opportunity to miss an opportunity, I respond, thinking about the way that UK official bodies have dismissed unproven ideas, such as onshore wind in the 1990s or lithium ion batteries a decade earlier, that have gone on to become major world-wide industries.

Statements of desirability are no substitute for proper plans

· One of the most eye-catching recommendations in the report is for 30,000 hectares of reforestation a year. This is what is supposed to push the net emissions from agriculture down to zero. The problem is that this has long been the UK government target (or, more precisely, 27,000 hectares is). We are talking about 0.1% of UK land area a year, principally coming from replacing low intensity sheep farming with woodland. The idea is excellent, although I think the ambition should be doubled or tripled, but no UK government has ever successfully taken on the animal farming industry. Replacing the growing of sheep and cows for meat with woodland is one of the most powerful things that can be done to reduce emissions. But the CCC has nothing to say on how it might be achieved. And, by the way, the crying need for improved retention of carbon in soils (not just for emissions reduction but for food productivity as well) is almost totally ignored.

· Similarly, the idea that the UK might start district heating plants in urban areas sounds wonderful. This idea has been floating around for decades. Nothing worthwhile has been achieved. The costs of building new heat networks in crowded urban environments are immense. Nothing will change this but there’s no examination in the CCC work of the practical difficulties.

Final point: The CCC’s job is to set targets, not produce fully worked-through policies. But, inevitably, a viable target needs a clear understanding of how it might be achieved. The CCC’s new report, which has raised the ambition for UK decarbonisation, should have been accompanied by a proper plan for achieving zero emissions. Instead it has just doubled down on its existing recommendations, first stated a decade ago, for a wildly impractical focus on CCS, nuclear, heat pumps and other dubious schemes. The things that are really shooting down in cost – solar, onshore wind, cheap electrolysis for making hydrogen – are curtly dismissed.

I’m sorry to be negative. The CCC does really important work but this report just isn’t good enough. More ambition please, less pandering to the perceived political practicability and more willingness to bet on the likely winners in the low carbon technology race.