Sorry, should have been clearer. I meant 50% solar/wind. It is because of peaker plants and because their renewables are often biomass, which just gets burned,

Sorry, should have been clearer. I meant 50% solar/wind. It is because of peaker plants and because their renewables are often biomass, which just gets burned, so effectively functions as a peaker plant. Edit: On reflection though, you may be right. I might have gone too low. The problem I'm trying to point out occurs when you don't have access to peaker plants. As long as there is enough peaker plant capacity you do not need much storage.