Greening our energy: sooner than you think

This blog follows a talk ‘Greening our energy: sooner than you think’ given in Frampton On Severn by Dr Richard Erskine, Education lead for NailsworthCAN on 26th September.

It will surprise many just how much progress the UK has already made on its journey to clean energy — and how much further it can go if we keep our nerve.

The story starts with a simple but powerful insight: most of the energy from burning fossil fuels is wasted as heat. Burn three units of coal to generate electricity and two are lost up the cooling towers. Fill a petrol car and two thirds of what you paid for disappears through the exhaust and radiator. This is the Primary Energy Fallacy — the mistake of assuming we need to replace all that wasted primary energy with renewables. We don’t. We only need to replace the useful energy that actually does the work. That means the electricity system of 2050 only needs to be roughly two and a half times today’s — not seven times, as some claim.

The UK’s progress to date has been remarkable. In 2010 it took eight units of primary energy to generate three units of electricity. By 2023 it took just four, and 2025 was the first full calendar year with zero coal generation. Renewables now supply over half of UK electricity, and the government’s Clean Power 2030 target — near-complete decarbonisation of the power sector — is firmly within reach.

The next big prize is fully electrifying transport and heating, which together account for around 40% of the UK’s carbon footprint. Here too, the economics are already tilting decisively in favour of the clean option. EVs are currently nine times cheaper to drive per mile than petrol cars — pure physics, because electric motors use three times less primary energy per mile. EV registrations have passed 25% of new car sales and the trend is irreversible.

Heat pumps tell a similar story. For a typical home using 12,000 kWh of gas a year, switching to a heat pump already saves around £234 annually at current prices — and that saving grows as the electricity-to-gas price ratio continues to fall. The ratio has already dropped from 4.7 at the start of 2026 to 3.3 today, and the direction of travel is clear. A heat pump delivering 3.5 units of heat for every unit of electricity consumed simply outperforms a gas boiler on cost,. For those concerned about climate change, the 1.7 tonnes of carbon saved every year is an added motivation to switch to a heat pump.

By 2035, on an optimistic but credible projection, an increasingly electrified UK could be running on double the electricity generation in 2010. We expect that EVs will dominate transport and heat pumps will begin to transform home heating. By 2050 we expect electricity generation to be about two and half times it is today., covering a fully electrified economy..

A 200-year-old Grade 2 Listed house in the Cotswolds, fully electrified with a heat pump and an EV, proves it can be done anywhere. If we don’t lose focus, greening our energy is genuinely sooner than you think.

For a long form but accessible, and illustrated version of this blog, that is fully referenced, please go to https://essaysconcerning.com/2026/10/08/greening-our-energy-sooner-than-you-think/