The electricity price month by month.

How many quarter hours the spot price was below zero.

When more power is produced than is used, typically on a sunny and windy day, the spot price can fall below zero. That is called a negative electricity price. Then it costs money to sell power.

Those are the quarter hours in which a system that sells without looking at the price pays to get rid of its power. The selling price goes below zero even before the spot price, because the feed-in tariff, the balance tariff and the trading fee are deducted. Read what you can do about negative electricity prices.

The difference between the cheapest and the dearest quarter hour on the same day.

That is the difference a battery can move power across: charge when power is cheap, and use it when it is dear. The bigger the difference, the more a battery is worth that day. The loss in the battery and the wear must be deducted before there is a gain.

The day with the largest difference is under the figure. Read when a battery pays off.

The quarter hour in the month when the full price was highest.

The full price is the spot price with the grid tariff, Energinet's tariffs, the electricity tax and VAT, calculated as on Electricity price today and tomorrow. The dearest quarter hour is often late in the day, when the grid tariff at most grid companies is highest and many people use power at the same time.

The spot price over the whole month.

The average spot price over all the month's quarter hours. It is the figure that best compares one month with another, because the grid tariff and the taxes are not in it.

Energinet's spot prices for each quarter hour, calculated by GridZeno.

GridZeno fetches the spot prices for DK1 and DK2 from Energinet's official dataset and uses them for each system's plan. The figures here are calculated from the same prices, with one price for each quarter hour.