How the estimate works
Electricity is billed in kilowatt-hours (kWh). A kiln’s energy use is its power in kilowatts multiplied by the hours it runs, and the cost is that energy multiplied by your rate:
The formulacost = kW × hours × duty cycle × rate per kWh
The duty cycle accounts for the elements switching on and off. A kiln controller holds the programmed climb by cycling power, so the kiln rarely draws full power from start to finish. The calculator starts at 60%, a planning assumption rather than a measurement; set it to 100% for a worst-case budget.
Two worked examples
| Kiln | Firing | Energy | Cost at 18.16¢/kWh |
|---|---|---|---|
| 1.8 kW (15 A × 120 V) | 8 h at 60% | 8.64 kWh | about $1.57 |
| 11.52 kW (48 A × 240 V) | 10 h at 60% | 69.1 kWh | about $12.55 |
Source: Rate: EIA U.S. average residential price, August 2026 (preliminary)
Where to find your kiln’s kW
- Look at the nameplate or the spec sheet. If it lists watts, divide by 1,000 (1,800 W = 1.8 kW).
- If it lists amps and volts, multiply them and divide by 1,000 (12 A × 120 V = 1.44 kW).
- Catalogue presets in the calculator use the amps, volts or watts shown in the product listing. Always trust the nameplate on the kiln you own.
What the number leaves out
- Tiered, time-of-use and demand pricing. If your plan charges more at peak times, use your actual rate for the hours you fire.
- Fixed monthly fees on your bill.
- Element wear, kiln shelves, cones and a vent fan. These cost money too, but not per kWh.
- Heat lost in a cold garage, which can stretch firing time.
For a real number, read your meter before and after one firing, or check whether your controller logs energy use, then compare with the estimate.
Questions
How much does it cost to fire a kiln?
It depends on kiln power, firing length and your rate. At the August 2026 U.S. average of 18.16¢ per kWh, a 1.8 kW kiln running 8 hours at a 60% duty cycle uses about 8.6 kWh, roughly $1.57. A large 11.5 kW kiln on a 10-hour firing comes to about $12.55.
Does a glaze firing cost more than a bisque firing?
Usually, if the glaze firing goes hotter or runs longer. Energy scales with the hours the kiln runs and how hard the elements work near peak temperature, so run the calculator once for each schedule you use.
Are the state rates current?
They are EIA averages for residential customers in August 2026, which EIA marks as preliminary. Your own utility plan can be higher or lower, so type your bill’s rate for the most accurate estimate.
What duty cycle should I use?
If you do not know, 50–70% is a reasonable planning range and 100% gives a worst case. Measuring one firing at the meter tells you your real figure.