Cost per hour of gaming at 26.32p per kWh (UK average), the live standard variable rate since 1 October 2026. ROG Ally figure is an estimate.
The short answer
Handheld gaming PCs are built to run on a battery, so they use very little power. A Steam Deck OLED draws about 24 watts while gaming. At today's UK rate of 26.32p per kWh, that's 0.6p an hour.
The ASUS ROG Ally and Ally X run their chip at up to 30 watts in Turbo mode when plugged in. Allowing for the screen and charging losses, it's reasonable to estimate about 35 watts from the wall, or 0.9p an hour.
| Device | Watts while gaming | Per hour | Per month (3 hrs/day) | Per year (3 hrs/day) |
|---|---|---|---|---|
| Steam Deck OLED | about 24 W | 0.6p | 58p | £6.92 |
| ROG Ally / Ally X (Turbo, estimate) | about 35 W | 0.9p | 84p | £10.09 |
| Mid-range gaming PC (for comparison) | about 330 W | 8.7p | £7.93 | £95.11 |
Charging while you play
If you game while plugged in with a flat battery, the handheld charges and runs the game at the same time. ChargerLab measured the ROG Ally pulling just over 60 watts from its official charger. That's still only 1.6p an hour, and it only lasts until the battery is full.
What does a full charge cost?
The Steam Deck OLED has a 50 Wh battery and the ROG Ally X has an 80 Wh one. Allowing about 10% for charging losses, a full charge costs about 1.4p for the Steam Deck and 2.3p for the Ally X. That's less than the price of a single sweet.
Ways to make it even cheaper
- Use a lower power mode. Capping the Steam Deck at 10 to 15 watts cuts power use by a third or more, and many indie and older games run just as well.
- Cap the frame rate. Limiting a game to 40 or 30 fps saves power and battery.
- Turn the screen brightness down. The screen is one of the biggest power users after the chip.
Compare with a full desktop on the gaming PC running costs page.
Sources: Notebookcheck, ChargerLab, Octopus Energy tariff data.