[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.