Negative electricity prices: what a price below zero means for you
A negative spot price sounds like free electricity. For a household it rarely is, and here is why.
Checked by Radif Partners · Editorial policy · Method and sources
A negative electricity price means the spot price for a quarter hour was set below zero in the day-ahead auction. For a household on a quarter-hour contract it lowers the price of that quarter, but power is rarely free. Energy tax of 36.0 öre/kWh before VAT and the grid transfer fee are charged per kWh whatever the spot price, and 25% VAT goes on the sum. With a 25 öre transfer fee, the spot price must therefore drop below minus 61.0 öre before the all-in price turns negative. At a spot price of minus 10 öre you still pay 63.8 öre/kWh. In the northern municipalities with reduced energy tax the threshold is lower, since the tax is 26.4 öre/kWh. On a variable monthly or fixed price, a negative quarter only shows as a slightly lower monthly average, or not at all. Try your own grid fee in the mini-calculator.
What do you pay when the spot price is below zero?
Your all-in price per kWh incl. VAT
63.8 öre/kWh
| Spot price | -10.0 öre/kWh |
| Energy tax + grid, excl. VAT | 61.0 öre/kWh |
| Spot price where the total hits zero | -61.0 öre/kWh |
Without mark-up. With a mark-up the spot price must fall further still.
The all-in price at different negative spot prices
| Spot price | Standard energy tax | Reduced energy tax (north) |
|---|---|---|
| 0 öre | 76.3 öre/kWh | 64.3 öre/kWh |
| -10 öre | 63.8 öre/kWh | 51.8 öre/kWh |
| -30 öre | 38.8 öre/kWh | 26.8 öre/kWh |
| -60 öre | 1.3 öre/kWh | -10.8 öre/kWh |
| -100 öre | -48.8 öre/kWh | -60.8 öre/kWh |
The table shows the all-in price falling in step with the spot price, but from a high level. Only when the spot price is more negative than tax and grid combined does the total drop below zero. In the Energy Markets Inspectorate’s 2026 data, the median transfer fee in the flat case is 21.8 öre/kWh and the lowest -0.0 öre/kWh, before VAT. Even on the cheapest grid a steeply negative spot price is needed.
The free-power threshold on different grids
| Grid (16 A flat) | Transfer before VAT | Spot where total hits zero, no mark-up | With 5 öre mark-up |
|---|---|---|---|
| Lowest in Sweden | -0.0 öre/kWh | -36.0 öre/kWh | -41.0 öre/kWh |
| Median | 21.8 öre/kWh | -57.8 öre/kWh | -62.8 öre/kWh |
| Highest in Sweden | 92.3 öre/kWh | -128.3 öre/kWh | -133.3 öre/kWh |
The threshold depends mostly on the grid. On the grid with the lowest transfer fee a smaller negative price suffices; on the dearest a very steep one is needed. The mark-up moves the line a few öre further. If your grid has peak and off-peak rates, which one applies when is in its price list.
A worked example with an invented day
Suppose tomorrow’s list has four quarters at minus 5 öre around midday and the rest of the day at 40 öre or more. The prices are examples, not market prices. You are on a quarter-hour contract, a grid with a 25 öre transfer fee and no reduced tax. During the negative quarters power costs you 70.0 öre/kWh, against 126.3 öre/kWh at 40 öre. An hour of drying at 3 kWh comes out SEK 1.69 cheaper. A real saving, but it comes from the quarter being cheap, not from power being free.
Why the price can go negative
The spot price is set in the auction where buy and sell bids for each quarter are matched, as Svenska kraftnät describes the day-ahead market. If, for a quarter, sellers would rather pay to offload power than switch off production, and demand is low, the price where bids meet can fall below zero. We show no spot prices and publish no statistics on how often it happens, because we have no free official source for that.
What to do in a negative quarter
On a quarter-hour contract a negative quarter is simply a very cheap quarter: a good moment to charge the car, run the dryer or heat water if you need to anyway. It is rarely worth using power just because the price is negative, since in most cases you still pay tax and grid. Paste the day’s prices into the calculator to see the all-in price of every quarter on your grid and with your tax, and where the cheapest window starts.
Negative quarters and power charges
It is tempting to pile everything into a few negative quarters: charge the car, dry laundry and heat water at once. If your grid has a power charge, that can still cost you, because the month’s highest load is billed per kilowatt. The saving on a few cheap quarters can be eaten by a higher peak, so spread the loads over the cheap quarters rather than starting everything together.
Negative prices and solar panels
For anyone with solar panels selling surplus, a negative spot price is the reverse: payment for power sold can be low or zero. Since 1 January 2026 the tax reduction for micro-production no longer exists either, which makes using your own solar power more attractive. More in selling solar power.
How the calculator handles negative prices
The calculator accepts negative numbers in the spot-price field and in the pasted list; a minus sign in front of the number is enough. It adds spot price, mark-up, transfer fee and energy tax and then applies VAT, exactly as when the price is positive. Lowest and highest come from the same list, so a negative quarter always shows as the day’s lowest. More on how the price is set in spot price and on the tax in energy tax on electricity.