I removed the extra links to sources for the electricity prices, but that's the average cost in EU, where I live.
https://ec.europa.eu/eurostat/web/products-eurostat-news/w/d...
Indeed, EPEX spot prices are between €0.30 and €0.39 today including taxes where I live. I've seen them go up to €1.10 during peak demand.
it is not the marginal price for household users, but the (average electricity bill : subscription + consumption) / (average consumption), so it will be higher than the additional kwh consumed.