Tool

Cold plunge electricity cost calculator

Type in your chiller watts, how many hours it runs and your electricity price. The formula is below, and so are the numbers I used as defaults.

Chiller power drawwatts500 W is the PlungeBox 1/2 HP listing. Use the watts on your own chiller's page.Hours running per dayhoursThe input nobody can know for you. Try 2, 4 and 8.Electricity pricecents/kWh17.30 is the EIA 2025 national residential average. Use your bill.

Per day2 kWh

Per 30 days60 kWh

Monthly cost$10.38

Per 365 days$126.29

The formula

Daily energy in kWh equals watts times hours running per day, divided by 1,000. Monthly energy is the daily figure times 30, and monthly cost is that times your price per kWh. The defaults are 500 W (the PlungeBox 1/2 HP chiller listing) and 17.30 cents per kWh (the EIA annual average residential price for 2025). Both come from pages I cite in my cold plunge electricity cost guide, where I work through the same sums by hand.

What the calculator cannot know

Hours running per day depends on your climate, insulation, how often you open the lid and how cold you set the water. No listing states it, so I leave it as the one input you have to choose. Check your bill for the real price per kWh: it may be split into supply and delivery, or priced by time of day. This is an estimate for planning, not a bill. See cold plunge cost for the purchase side.