Sunday, 8 September 2019

Let the sun take the strain

The Sun newspaper recently ran an article claiming that Britain will face power cuts unless the government steps up plans to build more nuclear energy plants’(1), a view reflected in a parallel Daily Mirror article which talked of fears over ‘energy shortage and lights going out' (2). This was in response to fact that the Conservative government has been unable to get private sector financial support for some of the new nuclear projects it wanted to see built, despite being able to tap consumers bills for some of the large extra cost. Labour said it could do better – in effect by using taxpayers money to partly fund new nuclear (3).

What seems to have escaped them both is that electricity use has fallen significantly in the UK in recent years- so we don’t need costly new nuclear plants. UK electricity use is now back to 1994 levels, around 15% down, in part due to the success of energy saving programmes and despite 18% economic growth over the period (4).

It is true that, as we phase out coal use (all of it is planned to go by 2025), and as the old nuclear plants close, we will need more energy inputs, but there is no shortage of low cost green energy options. As the government Business and Energy Secretary Greg Clark said ‘The cost of renewable technologies such as offshore wind has fallen dramatically, to the point where they now require very little public subsidy and will soon require none’ (5).

He could have also mentioned on shore wind and PV solar, now both vying to be the lowest costs energy sources of all, already able to deliver power at around half the cost of the power that  may eventually be produced if the Hinkley nuclear project is completed, which might be sometime around 2027. However, the government has opposed on shore wind and has pulled support for PV solar. So we are left with new nuclear, offshore wind and some large controversial biomass projects, including some using forestry-derived wood pellets imported from the USA.

You don’t have to be an energy expert to see that there are some problems. Offshore wind is fine and there are some very large schemes going ahead. We already get 33% of our power from renewable energy projects like this. We are likely to able to meet at least half our electricity needs from renewables by 2030, and could, given proper support, get to near 100% by 2050.  However, the real problem is not electricity use, but heat and transport energy. We have not done at all well there so far.

The governments plan is to get us to switch from using North Sea gas for heating, to using electricity to run domestic heat pumps- so out goes your old gas fired central heating boiler unit and in comes an expensive new bit of kit. That, it is proposed, will be mandatory for all new houses from 2025 (6). In parallel the governments want to us to switch over to using electric vehicles. All of this this means more electricity will be needed- a lot more (7).  The UK gas grid handles about 4 four times more energy than the power grid and vehicle fuel use is even large than that. Shifting all of that over to electricity supplied by the grid will be hard- if not impossible, even with a lot of new nuclear plants and a major grid expansion programme. 

There is an alternative. If we went for a very large renewables programme, with onshore and offshore wind and PV solar, scaled up to meet power demand most of the time, then, since renewable outputs and demand vary, at times there would be surplus output – when wind and solar was high but demand for power low. That surplus power could be quite large and could be used to make carbon-free hydrogen gas by the electrolysis of water.  That green gas could be stored, with some of it being used later to make electricity again, when there were lulls in wind and solar availability, while some of it could be fed into the gas main, instead of fossil gas, to supply heat. So we would keep the gas grid and you could keep your boiler, although some adjustments would have to be made, as happened when we switched from the old Town gas, made from coking coal, to North Sea gas in the 1970s.

In urban areas there would be a role for heat networks - district heating, fed by biomass or green gas fired Combined Heat and Power (CHP) plants, with large heat stores, these also being topped up by solar heat, as is done in Denmark.  CHP plants are flexible- they can vary the ratio of heat to power out to match demand. That would help with balancing the variable output from renewables.  And needless to say, energy waste would be squeezed out of the system- by improved buildings and the more efficient use of energy.

On the transport side, while electric cars have their appeal, if using green electricity, we should really be thinking more of public transport, trains and trams, and, for larger service and working vehicles (vans, trucks, tractors, buses) biogas and hydrogen are arguably better fuels. In the system outlined above, we would have green gas available for them, which could be toped up with biogas made from domestic food, municipal and farm wastes.  It’s harder to see a way forward for aircraft, which currently use untaxed fossil fuels, but there’s a race on between systems using battery power and those using biofuel/hydrogen. The later can also be used for ships- some already use LNG (Liquified Natural Gas) instead of marine diesel.

The simple message from all this is that we don’t need nuclear- renewables can do it all. It is conceivable that nuclear could do some of it- using nuclear plants at night, when power demand is low, to make hydrogen. However, quite apart from all their other problems, nuclear plants are not suited to frequent rapid changes in power output, so they would be no use in balancing variable renewables. Whereas the system described above, based on direct and indirect forms of solar energy, would do that well- all without the need for fossil fuel, or nuclear power.        


(1)www.thesun.co.uk/news/8654311/mps-fear-electricity-shortage
(2)www.mirror.co.uk/news/politics/tory-energy-failures-raise-fears-14149517
(3) https://labour.org.uk/press/tory-energy-cancellations-risk-power-20-million-homes-rebecca-long-bailey/
(4) www.carbonbrief.org/analysis-uk-electricity-generation-2018-falls-to-lowest-since-1994
(5) www.gov.uk/government/speeches/statement-on-suspension-of-work-on-thewylfa-newyddnuclear-project
(6) www.gov.uk/government/news/spring-statement-2019-what-you-need-to-know
(7) https://uk.reuters.com/article/uk-britain-energy-demand/uk-power-demand-to-soar-on-plans-to-end-gas-home-heating-research-idUKKCN1R0003

This was produced initially for the BANNG anti-nuclear group in Essex: www.banng.info

An edited version appeared in their Regional Life section

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