UK energy consumption is falling fast. In 2006 the country consumed the equivalent of 236 million tonnes of oil. Provisional figures released in the last few weeks suggest that this figure was 198 million tonnes last year, a fall of 16%, or about 2% a year.(1) In 2014, the cut was steeper, at around 2.5%. In other words even the fairly robust economic growth of last year failed to stop the downward trend. The last time total energy demand was below the equivalent of 200 million tonnes of oil was in the late sixties, almost fifty years ago.

I chose 2006 because in David MacKay’s classic book on Sustainable Energy, he calculated that the figures for that year meant that each person in the UK needed 124 kWh a day. Some of this energy we consume directly in the form of petrol, gas heating or electricity. Some is embedded in the products we buy or the services we benefit from.

As total energy need has fallen, the UK population has grown since Prof. MacKay did his research. Calculate the MacKay number today and the figure for the average person is now below 100 kWh a day. This is probably the first time since the Second World War that the number has been this low.

Put another way, instead of needing 5 kW of energy all the time, as we each did in 2006, we now need just 4 kW. (To put these numbers in context, an individual working hard at manual labour will generally be producing no more than 250 W). Even as we bemoan the lack of progress on decarbonisation, this is a remarkable change in such a short period. And it is spread across all fossil fuels. Coal use is down 26%, gas 23% and oil 15%.

Nevertheless, fossil fuels still represent 85% of all energy use in the UK. This figure is falling, but only slowly. When MacKay did his research, non fossil sources, including imports, gave the country 10% of its energy. Now the figure is about 15%. Biomass – now almost as important as nuclear - gives us 5%, wind less than 2%.

The important related point is of course that energy efficiency has been far more important in reducing fossil fuel use than the growth of renewables. Fossil consumption is down by an equivalent of 45 million tonnes of oil, but all non-fossil sources, including French nuclear electricity are up by only by 7 million tonnes, about a sixth as much.

Actually, the problem is even worse. Look again at the chart above. The share of non-fossil sources has barely shifted since the mid nineties. Then we got 25 million tonnes of oil equivalent energy from nuclear and other low-carbon sources. Last year the figure was up just 5 million tonnes.

This issue was barely discussed in the election. The UK is fast becoming the only place in the developed world (with the possible exceptions of the Netherlands and Poland) in which there is an implicit assumption that the energy system of 2050 will still be based on fossil fuels. The work to show that the switch to low carbon sources is inevitable, beneficial and easily within our grasp seems yet to begin.

(1) These figures are temperature adjusted.

(2) The figures in this note are largely taken from DECC's most recent Energy Trends.