How it works

Each delivery day is fetched from the Nord Pool day-ahead auction, in euro, for the Baltic and Nordic bidding zones. We do not scrape a supplier's consumer tariff.

If the auction for that day is not published, the page says so. We do not fill the gap with a made-up price.

The auction now clears every quarter-hour. Households still think in hours, so each bar is the average of the quarters inside a local clock hour.

The clock is the zone's own: Riga, Helsinki, Stockholm, Oslo or Copenhagen. The delivery date itself stays the Central European auction date.

Flexible energy is priced once at the day's average and once in the cheapest three-hour window. The difference, converted from €/MWh to euros, is the figure on the savings page.

A battery is a separate, simpler cycle: charge in the cheapest hours, discharge in the dearest, keep a 90% round trip, and never charge and discharge in the same hour. It is a heuristic, not a full optimiser.

The public score predicts each quarter-hour with the same quarter-hour one delivery day earlier. Mean absolute error and root mean square error are computed from the auction, over the recent delivery days that came back.

A later model has to beat that baseline on a stored history. Until it does, this is the number on the accuracy page.