> In the UK in winter we regularly have periods of 5 cloudy days

True, but then for the UK solar power isn't the right thing for winter, hence why we need a massive mix of other stuff.

Also we have the advantage that france isn't that far away.

In the UK battery is about grid stabilisation, as in making sure that it hums at 50hz rather than 49.

Battery revenues are shifting away from stabilisation now from https://cn-cob.com/info-detail/2026-uk-energy-storage-market...:

> the focus of energy storage has shifted from frequency services to energy arbitrage. Due to market saturation, the share of frequency services in the revenue stack has significantly declined, from 80% in 2022 to just 20% in 2024. Looking ahead to 2030, we expect energy arbitrage to dominate the revenue stack, with most revenue coming from participation in the balancing mechanism.

	▲	KaiserPro 42 minutes ago \| parent [-]
		Indeed, in the same way that solar has now peaked in spain/portugal in its current config. They are moving to solar+battery to absorb solar mid day and replay that in the morning/evening. (that doesn't really apply in the UK because of the rain) As more renewables come on stream and the grid gets more complex, batteries are going to plug holes. Energy Arbitrage is usually a good thing, so long as its regulated to for the customer, not the battery people. the point is that battery capacity is being deployed to even out the 5-9pm peak, which means that we are much much less dependent on gas turbine generators (which means less price pressure linked to LNG prices, if you're not into the co2 aspect)