How Much Electricity Does an Electric Sauna Use?

An electric sauna uses roughly its heater rating in kilowatt hours for every hour of full-power operation. A 6kW heater at full draw uses 6 kWh in an hour. Real sessions use less than that, because the heater pulls hard during warm-up and then cycles on and off to hold temperature.

Two phases of a session

Every sauna session has two distinct parts, and they draw very differently.

• Warm-up. From cold, the elements run at or near full power to bring the room up. This is where most of the electricity goes. Expect roughly 30 to 45 minutes for a well-built, correctly sized indoor room, longer for a large or outdoor sauna in winter.
• Holding temperature. Once the room reaches your set point, the thermostat cycles the elements. The heater is only drawing power part of the time, so the second hour of a session costs noticeably less than the first.

Putting numbers on it

Take your heater rating, decide how long you run it, and multiply. A 6kW heater run for a 45 minute warm-up at close to full draw plus a 30 minute sit at partial draw will land somewhere under the 7.5 kWh that a full 75 minutes at full power would give you. Multiply the kWh by the rate on your hydro bill for the dollar figure. The full method is in what it costs to operate a sauna.

How to use less

• Use the timer so the room is ready when you are instead of running long.
• Keep the door shut during warm-up.
• Make sure the room is properly insulated, which matters more than anything else.
• Size the heater correctly for the room, so it is not fighting a losing battle.
• Sauna back to back with family while the room is already hot. The expensive part is the warm-up, so a second session straight after the first is cheap.

Does the heater size change the total much

Less than people assume. A bigger heater draws more while running, but it also gets the room hot sooner and then settles into cycling. An undersized heater in a big room is often the worse deal, because it runs flat out for a long stretch and may never comfortably reach temperature.

Procraft builds Western red cedar saunas and makes four CSA-approved electric sauna heaters from 4.5kW to 9kW. See the heaters, read about Western red cedar, or see how installation works.