Charge your electric car cheaply
An electric car is the biggest flexible load in most homes: 3,000 kWh a year is typical. Charging it at the right time is worth more than everything else on this site put together.
What it’s worth
wattslot simulated a year of real 15-minute prices and grid tariffs (October 2025 – September 2026, VAT included) for a car that charges at 7.4 kW, is plugged in at 17:00 and must be ready at 07:00:
| Charging | DK2 · Radius Elnet | DK1 · N1 |
|---|---|---|
| Charge on plug-in | 6,210 kr. | 5,630 kr. |
| Cheapest quarter hours | 3,217 kr. | 3,170 kr. |
| Saving | ≈ 2,990 kr. (−48%) | ≈ 2,460 kr. (−44%) |
| Of which beyond a 00:00 timer | ≈ 550 kr. | ≈ 575 kr. |
Most of the saving comes from one thing: not charging between 17:00 and 21:00. A plain timer that starts at midnight gets you most of the way; picking the cheapest quarter hours adds about 550 kroner a year on top.
How to set it up
- Easiest: set the car’s or the charger’s timer to start at 00:00.
- Better: a charger or app that charges in the cheapest quarter hours — ideally by the full price including your grid tariff, not just the spot price. The two often pick different hours.
- At 7.4 kW, a quarter hour adds about 1.85 kWh, roughly 11 km of range.