Comment by isostatic | Hacker News Reader

Comment by isostatic | Hacker News Reader

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In the UK we require a peak load of 40GW, average about 35GW.

Wind varies a lot. On May 4th in the UK it was generating nearly 9GW, but on May 1st was generating 220MW.

Over the last year it's generated 15% of the UKs electricity demand, so increasing by 10 fold would mean it could generate everything, if there was infinite storage.

Lets assume we start off with 100 lots of South Austrailia batteries - so 13 GWh of storage, and fully charge them on May 13th 2018 at 22:30.

After 40 minutes we've added 5.5GWh, but we've taken out 12GWh, and in the next few minutes it stops.

OK, lets go for 130GWh Storage - or 1,000 SA batteries.

That's great, we're doing well. Until May 14th at 07:50, when the battery is full, so we throw away the energy. That's great, we can last until May 17th - less than a week.

So we start with a battery that's got a total capacity of 10,000 SA batteries - 1.3TWh, and starts off full.

Unfortunately on June 1st it wasn't very windy, and we've been drawing down on our batteries for 2 days. The lights go off on June 1st at 10:50.

For the UK to be wind powered for the last year, we'd need 1) 10 times the current wind production 2) A battery or other storage capacity of 13 TWh -- that's 100,000 batteries the size of the one Musk delivered to South Australia.

Or 1) 100 times the current wind production 2) A battery or other storage capacity of 300 GWh -- that's 2,500 batteries the size of the one Musk delivered to South Australia.

Or 1) 1000 times the current wind production 2) A battery or other storage capacity of 500MWh -- that's 3 batteries the size of the one Musk delivered to South Australia.

I'm not sure if it's possible to get 1,000 times as much power from wind as we currently do (21TW of production, generating 57TWh over the course of the year), but it would generate an insane amount of excess energy at windy times.

That simplistic calculation is an entirely fictitious scenario. It ignores the fact that energy grids are integrated. Once your wind plants are distributed in a wider area they won't all see the same weather and the differences even out much better.

I thought it was acknowledged in the industry that interconnects need to be built out to distribute wind power better. Why did you choose to ignore that in your calculations?

Well.. brexit means brexit

What's your point? You don't need to be in the EU to link up to your neighbours. See for example North Sea Link for a project which is actually relevant to the discussion here.

That's assuming an infinite grid across the UK, I don't have the wind generation figures of other countries on a per-minute basis. The current integration is about 10% of the UK's demand.

The reason I'm "ignoring" it, even with an infinite grid across europe, when the wind is blowing in the UK's wind farms in the north sea, it's also blowing in the north sea for Denmark - UK wind production peaks match that of Denmark and Netherlands peaks.

The figures are based on real figures in the UK from the last 12 months. The UK is the world leader in offshore wind power, with Netherlands, Germany and Denmark having their farms in the same location

What happens when the wind isn't blowing in the North Sea, and UK, Denmark and Netherlands are all running out?

That's not to say we shouldn't be pushing to double, triple or even quadruple wind production in the UK and the North sea especially, but we'll still rely on gas to fill in the quiet days for a long time yet. Dogger Bank alone can generate 110GW of energy, which is great, but that would mean when the North Sea is quiet we need to find 110GW from elsewhere.

Sadly political changes in the UK, first in 2015, then in 2016 through today, have reduced the investment in wind power.

An "infinite grid across the UK" really isn't so big, though. There are US states with larger power grids than the UK.

Which, I guess, both shows how possible it is to spread load around the UK, and shows how massive a problem anything in the US is to solve.

Thanks for the details. I still don't understand the point of calculating national scenarios with only wind and battery storage.

In New Zealand we balance wind availability with fast cycle natural gas turbine plants.

Wind goes up and down. That's fine. But there needs to be something to cover those gaps. And it's either 2,500 batteries, or some gas turbines.

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