The quarter-hour price: electricity priced 15 minutes at a time
The spot price is now set separately for every quarter hour. That opens new ways to save, but only on certain contracts.
Checked by Radif Partners · Editorial policy · Method and sources
The Nordic power exchanges moved to a 15-minute time unit on 1 October 2025, so the Finnish bidding zone now has a price for every quarter hour, normally 96 a day. Prices used to be hourly. On the page’s update day, 17 October 2026, the quarters within an hour differed by 1.15 c/kWh on average and by up to 3.81 c/kWh including VAT. The quarter-hour price only shows on your bill if your contract is priced by quarter; on an hourly spot contract the hour’s price is the average of its four quarters, and on a monthly-average or fixed contract quarters have no direct effect. Those who can time large loads, such as car charging or a water heater, precisely into the cheapest quarters gain most. The home page calculator shows every quarter’s all-in price with transfer and taxes.
How much does shifting use save?
Saving per year
€65
| Gap per kWh incl. VAT | 6.27 c/kWh |
| Saving per week | €1.26 |
On general transfer, transfer and tax do not change by hour, so the saving comes from the spot price.
Why prices moved to quarter hours
Europe’s electricity markets are being harmonised, and balancing, keeping generation and consumption in step, moved to 15-minute periods in the Nordics first. Day-ahead auction prices followed on 1 October 2025. A shorter time unit better reflects variable wind and solar output and rapid changes in demand, and it gives flexible consumption a sharper price signal.
In practice the day-ahead auction is still held once a day at noon Central European time, and results appear in Finland at about 13:45. The change concerned the resolution of prices, not the publication time. Prices are shown on Nord Pool’s site and the ENTSO-E Transparency Platform.
The day’s quarters and hours
The update day’s 96 quarter-hour prices are in the home page calculator’s chart. On Helsinki’s general transfer the cheapest quarter cost 9.17 c/kWh all-in and the cheapest hour 9.30 c/kWh on average. The gap between the cheapest quarter and the cheapest hour shows how much quarter-hour pricing can at best help a short load.
Today’s cheapest window and the saving
Cheapest window starts 04:30
9.49 c/kWh
| Day average | 11.33 c/kWh |
| Saving on this use | €0.37 |
Helen Sähköverkko, general transfer, spot contract. Prices of the page’s update day.
What quarter-hour pricing means for each contract
- Quarter-hour spot contract: each quarter’s use is priced at that quarter’s spot price plus margin. The sharpest signal and the biggest gain from flexibility.
- Hourly spot contract: the hour’s price is the average of its four quarters. Timing to the hour is enough.
- Monthly-average contract: the price is the month’s average and timing has no direct effect.
- Fixed price: energy costs the same at every moment. Timing only matters on time-of-day or seasonal transfer.
The Energy Authority’s comparison shows which spot contracts are offered in your area. Compare margins too.
How much timing saves
The saving is the use you shift times the price gap. On general transfer the gap comes from spot alone, since transfer and tax are the same every quarter. On time-of-day transfer cheaper night transfer widens it. The calculator above shows the saving from the use you shift each week and the size of the spot gap. The biggest savings come from large loads: car charging and a water heater use many times what a washing machine does.
Watch the power fee
If your transfer product has a power fee, running every load in the same cheapest quarter can lift the month’s peak and the fee. It is then often better to spread loads over several cheap windows. Read the power fee guide and see typical cheap hours in the cheapest time guide.
Example: a water heater on quarter-hour prices
A water heater usually heats for a few hours at night and can be set to run in exactly the cheapest quarters. On hourly prices the control picked whole hours; on quarter-hour prices it can skip one expensive quarter and resume in the next cheap one. One night’s saving is small, but it accrues every night all year once the control is set.