[bshipp]

Isn't it the opposite? A 10x variation would be an incentive to invest in storage systems that capture energy at night and release it during the day.

Think a high-altitude reservoir where water is pumped up all night and then released all day when it's required.

[belorn]

Storage that has a reliable 365 charge/discharge cycles each year can be economical viable, especially when the discharge window of peak price is just a few hours. Solar + lithium battery work great in countries where the primary source of energy can be solar every day of the year.

Wind power doesn't work like that. Instead of a daily pattern of high and low supply, you get random amount of weeks and days of high supply followed by random amount of weeks and days of low supply.

Storage need to discharge in order to generate profits. If you get 30-50 discharge cycles each year, then those periods need to provide profits for the cost of 365 days of operations and it also need to repay the original investment.

One way to get around this is with subsidies. This is how some fossil fuel plants operate, called "reserve energy". When the wind blow they don't run the generator, but they still get paid through tax money. Then they start the engines when the wind isn't blowing and demand exceed supply. This scheme helps to reduce the peak price in northern Europe, through obviously it isn't really that cheap. It mostly just hide the true price behind subsidies.

[fallingknife]

Yes, the fact that such a strong incentive exists, and yet it hasn't been done, shows that cost is so much that even a 10x price difference isn't enough to pay for it.

[bshipp]

I'm pretty sure it's done quite frequently. It's a pretty simple battery system with--apparently--an 80+% round-trip efficiency to it.

The biggest problem is getting permission to move that much water around. I live next to a lake and shudder at the regulatory hurdles I'd encounter building something like this. There'd be at least 4 government agencies before I even negotiated to sell to the public utility.

https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

[ncmncm]

It would be obviously stupid to build storage that there is not enough renewable power to charge up from, yet. So, its not having been built yet only proves money is better spent on generating capacity.

[fallingknife]

Makes no difference what generates it. OP said that power prices vary by 10x from peak to trough. If you charge from the grid when cheap you can make 10x per cycle selling it back.

[ncmncm]

Then it is expected the situation will not last long enough to make a profit from.