An interesting piece in E&T.
This comes up with a requirement for seasonal timescale storage of energy using hydrogen to reduce the installed wind power capacity in 2050 from 600 GW down to a mere 190 GW.
The full paper is downloadable here:
So 600 GW is one hundred thousand 6MW wind turbines. Assuming that these would need to be separated by 1 km to avoid blocking each other’s wind (is that a sensible guess?) this would require an area of around 300 km x 300 km. Where shall we put them? The proposed 190 GW will require an area of around 170 km x 170 km, still not easy to install, if offshore they would have to be in deep water or floating.
What are the resources required to build them? Figures are hard to find but I have a report from the United States Geological Survey which is a little old but gives weights of various materials per MW. Newer optimised designs may use less, offshore probably uses more.
Table 5, page 12, gives 100 tonnes of steel per MW and 400 tonnes of concrete per MW.
190 GW installed capacity will require 19 million tonnes of steel and 76 million tonnes of concrete.
Not impossible amounts when spread over a couple of decades, but a lot of energy to pay back.
Accepted practice for spacing is 6-10 rotor diameters. the diameter for a 6MW unit will be ~ 150m, so 1km is certainly not wild of the mark, and could be more.
The North sea is typically 50-100m deep so support will be an odd mix of sea floor and floating
The UK used to have a big hole under the North Sea, called the Rough storage facility, and it was used to store natural gas. It was shut down in 2017 because everybody knows that there is plenty of natural gas, and there isn't going to be a shortage any time soon. 😖
We have a government that is totally incapable of planning anything to do with energy supply. Everything is left to wishful thinking and blind luck.
We will only get large scale energy storage once a commercial organisation has decided it's cost-effective to build it. And it will most likely be bought in from overseas because we're not making any effort to develop grid-scale storage solutions here.
It was recently reported that the first new pumped storage station for many years was being proposed.
And that expansion at another site was being considered.
The present high gas price will encourage such schemes, AT PRESENT we have no surplus wind power to store. That however will likely change as more wind turbines are built.
To be fair Rough is a salt cavern, and had started to leak, but I agree, some form of refurbishment /repair or an on-land replacement for the lost long term storage would have been a sensible engineering approach