Record ‘Low Carbon’ Power Is A Problem, Not An Achievement
Following the hoopla from NESO about record “low carbon electricity” last week, it is worth looking at the overall picture for the day
Source: gridwatch.co.uk
Don’t worry too much about the individual colours at this stage – just focus on the yellow splurge representing solar power.
The second band up from the bottom is gas, which conveniently ramps down when solar power peaks, and is there to meet demand when the sun goes down.
But I am more interested in the effect of inherent intermittency of wind and solar on the grid.
Solar power peaked on that day at 15,158 MW just after noon. But under Miliband’s plan to triple solar power by 2030, the same weather conditions would see this figure rise to about 45,000 MW.
Wind power would also triple by 2030 under Miliband’s plan. Nuclear provided a steady baseload of just over 5000 MW yesterday – for the sake of argument, let’s assume that figure remains unchanged in a post 2030 scenario, not unreasonable based on Hinkley C and Sizewell B.
Putting all this together, this is what the non-dispatchable grid supply would look like in 2030, ie generation that cannot be easily switched on and off:
Sources: https://bmrs.elexon.co.uk/generation-by-fuel-type and https://www.solar.sheffield.ac.uk
The chart below compares total non-dispatchable power with demand:
In theory, we might expect to see slightly higher demand in 2030 than now, but, given the slow uptake of EVs and heat pumps, I doubt whether it will be much different.
We can see immediately that there is a massive problem – there is a huge surplus of power in the middle of the day, indeed from 9am through to 5pm.
In theory it should be possible to store all of this surplus during the day, and use it to fill the shortages at night. But the cumulative surplus during the day builds up to 150 GWh, which is much higher than the storage we currently have available.
According to NESO Future Energy Scenarios, we just have 10 GW, with storage of 37 GWh. Even their forecast for 10 years time is still only 65 GWh:
Source: neso.energy
The weather that day was by no means unusual, and it is certain that power surpluses will be considerably higher on days in mid summer.
There is another problem with the “storage solution”. Battery storage operators, particularly those linked to solar farms, need to make money.
Their business model is to sell the stored electricity when prices are high. For a solar farm, that means higher than their CfD strike price. There is no point in just discharging the batteries at night, if market prices then are not high enough to cover energy losses, depreciation and other costs.
Supposedly, power prices are normally lower at night anyway! Meanwhile, the solar farm is protected from ultra low market prices during the day, because they will still get their CfD guaranteed price.
In short, the batteries are not there to balance the grid, they are there to make money.
And to virtue signal of course.
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