Here’s my initial take on DECC’s new energy planning toy, My2050, launched this week. The aim is to cut emissions to 20% of 1990 levels by 2050 and keep the lights on. There are screenshots of my choices below.

Of course, the emissions target is probably too generous and fails to reflect the latest science, and given the limitations of the choices presented, the tool is inevitably crude. But it presents some interesting dilemmas even so.

The first is how hard it is to hit 20% without completely electrifying space heating and transport fuel, which is something I have advocated for some time. This really is the only way to decarbonise home heat and transport; biogas from anaerobic digestion will help, but the resource doesn’t look big enough to supply both sectors, certainly in Britain.

The next is the model’s sensitivity economic growth; you seem to have to opt for pretty much steady state manufacturing to have any chance of hitting the target, implying zero growth for forty years. This may be right, but did DECC really mean to say so?

On the plus side, you can cut emissions by four fifths with relatively little behaviour change: room temperatures at 17C rather than 17.5C today, and 25% of journeys taken by public transport, which would make my 2050 easier to sell politically. I’ve assumed three quarters of homes have additional insulation.

In terms of the energy supply, it’s encouraging the target can be achieved with no nuclear (should you object); no CCS (not commercially available yet); and only moderate growth in onshore wind (double today’s capacity). But to make it work you need maximum offshore wind, wave, hydro and solar. A scenario including 40,000 offshore wind turbines, against just 436 today, may sound a stretch, but this is a forty year view. It would require huge amounts of balancing fossil capacity, energy storage, smart grids or a supergrid. Alternatively, you can trim the offshore renewables by half and raise nuclear to four times today’s capacity and achieve the same result.

One drawback is that the fossil fuel supply is lumped together in a single variable: no accounting for peak oil here. Nor is the fossil electricity generating capacity broken down. It would be far better if the model controlled oil, gas and coal supplies and generation individually. I opted for a fossil fuel supply that halves by 2050.

When I clicked ‘submit’ I was surprised find I had condemned a land area the size of Wales to grow nothing but biofuels, when I thought I had set that slider to zero. It turns out that’s the minimum setting, which is clearly wrong: there’s not enough land in Wales or anywhere else, and it should be possible to opt for zero. DECC should disagregate anaerobic digestion and sustainable forestry-based fuels from arable biofuel crops, and spell out the impact on agriculture. It should also put price tags on all the scenarios.

Click to enlarge.

Click to enlarge.


  • Andrew DeWit

    Looks pretty serious indeed. The Japanese elite are still desperately ignoring it, fixated on domestic politics.

    • David – thanks very much, I’ll take a look. But what do you make of my comment about the 20% target depending on zero economic growth to 2050? I couldn’t hit the target without assuming no growth. Is that really what your model is telling us?

  • Lana

    I am also surprised by the inclusion of Biofuels as a necessary component. What will be the impact on food prices? We are going to need more land area available for agriculture in the UK, due to rising oil prices, since global agriculture is heavily dependent on oil (fertilisers, pesticides, transport). If vast areas of land are turned over to biofuels to power our cars, its likely millions of people around the world will go hungry. So the medicine could be worse than the disease (climate change).

  • Tony Weddle

    Anaerobic digestion requires bio-waste. Where will this come from and what are the impacts of diverting it from, say, enriching soils? I recently came across some data that claimed the world uses about half the energy that all plants absorb from the sun and convert into biomass. In the US, the figure is twice as much energy is consumed as is contained in biomass. I assume that the figure is much worse in the UK and, of course, we need to grow some food and have some habitat for other species. So you’re right to doubt anaerobic digestion’s scalability – I don’t think there is any chance at all.

    Zero growth to achieve targets also sounds likely (probably even negative growth), but I doubt any government organisation would admit to that.

    Electric transport won’t help in the long term as vehicles require a prodigious amount of oil to produce (currently, anywhere from two years petrol use upwards, I believe).

    • Tony, there’s no competition between biogas and fertilizer; anaerobic digestion produces both. The UK biogas resource is estimated at about the equivalent of about 15% of total transport energy.

      Conventional cars also take a lot of energy to produce, but unlike them, EVs require no oil for fuel and can be powered on renewable electricity. Obviously we have to find alternative energy sources to replace fossil fuels in all sorts of manufacturing applications.

  • andrew needham

    Pleased to read your article in Energy World this month re DECC 2050.

    The agricultural sector is responsible for 8% of the UK’s greenhouse gas emissions, with particular problems associated with nitrous oxide and methane.

    Its difficult to see how this could be achieved for agriculture.

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