How do you calculate furnace energy cost?

Multiply run energy consumption by your blended utility rate and the capture percent, then add the demand or idle adder. With 1,800 kWh at $0.12/kWh and 100% capture, the captured cost is $216; adding a $75 adder gives a total of $291.

What is a good energy cost per kWh for a heat-treat furnace?

The metric here is total dollars, but the derived cost per entered kWh in the example is $0.16/kWh once the $75 adder is spread over 1,800 kWh. Anything far above your raw $0.12 rate signals heavy demand or idle penalties worth attacking.

Why include a demand or idle energy adder?

Electric furnaces draw peak demand during ramp and hold heat between loads. Those demand charges and idle losses are real costs not captured by kWh times rate alone, so the $75 adder pulls them back into the per-run number.

Should I use a blended rate or my off-peak rate?

Use a blended rate. A blended $/kWh folds energy, demand, and time-of-use tiers into one figure, so quoting off your cheapest off-peak rate alone will systematically under-cost your loads.

What does the capture percent do?

It lets you cost only a fraction of a run when a furnace is shared, partly loaded, or processing mixed jobs. At 100% you charge the full 1,800 kWh to the job; at 50% you would charge half.

How can I lower furnace energy cost per run?

Increase load density so more pounds ride each kWh, schedule back-to-back runs to cut idle reheating, and shift cycles off peak-demand windows. Each directly trims either the captured energy or the demand adder.

Heat Treatment, Furnaces & Thermal Processing calculator

Furnace Energy Cost Calculator

Furnace energy cost is the dollar value of electricity (or its equivalent) consumed to heat-treat a load, plus the demand and idle charges that hide on every utility bill. Heat-treat supervisors, captive in-house metallurgists, and commercial hardening shops use it to cost a batch, defend a quote, and decide whether an aging box furnace is worth re-lining or scrapping. Because thermal processing is one of the most energy-intensive steps in metalworking, even a small per-run swing compounds across thousands of cycles a year. Getting this number right is the difference between a profitable austenitize-and-quench cycle and one that quietly loses money on demand charges.

What this calculator does

Estimate furnace energy cost for a heat treat run using kWh or therm consumption, utility rate, cost capture percent, and fixed demand or idle cost.
Use it when energy cost needs to be visible for a batch furnace, continuous furnace, oven, kiln, vacuum furnace, or induction heating route.
It computes the total energy cost of one furnace run by valuing the metered kWh at your blended rate, applying a capture percentage, then adding demand and idle charges.

Formula used

Captured furnace energy cost = run energy consumption × blended utility rate × energy cost capture percent
Total furnace energy cost = captured furnace energy cost + demand or idle energy adder

Inputs explained

Run energy consumption:
Blended utility rate:
Energy cost capture percent:
Demand or idle energy adder:

How to use the result

Use it when quoting a heat-treat job, building a standard cost per load, or comparing the operating cost of competing furnaces or schedules.
The blended utility rate must already fold in demand ratchets and time-of-use tiers; if you use a flat off-peak rate only, the result understates what the meter actually bills.

Current U.S. benchmarks

As of Apr 2026, industrial electricity averages 8.7 cents per kWh across the U.S. (EIA), up 5.5% from a year earlier. State averages range widely, so plants should confirm against their own tariff.

Common questions

How do you calculate furnace energy cost? Multiply run energy consumption by your blended utility rate and the capture percent, then add the demand or idle adder. With 1,800 kWh at $0.12/kWh and 100% capture, the captured cost is $216; adding a $75 adder gives a total of $291.
What is a good energy cost per kWh for a heat-treat furnace? The metric here is total dollars, but the derived cost per entered kWh in the example is $0.16/kWh once the $75 adder is spread over 1,800 kWh. Anything far above your raw $0.12 rate signals heavy demand or idle penalties worth attacking.
Why include a demand or idle energy adder? Electric furnaces draw peak demand during ramp and hold heat between loads. Those demand charges and idle losses are real costs not captured by kWh times rate alone, so the $75 adder pulls them back into the per-run number.
Should I use a blended rate or my off-peak rate? Use a blended rate. A blended $/kWh folds energy, demand, and time-of-use tiers into one figure, so quoting off your cheapest off-peak rate alone will systematically under-cost your loads.
What does the capture percent do? It lets you cost only a fraction of a run when a furnace is shared, partly loaded, or processing mixed jobs. At 100% you charge the full 1,800 kWh to the job; at 50% you would charge half.

Last reviewed 2026-05-12.