Power Plant Heat Rate Calculator

Work out power plant heat rate instantly with clear inputs, formula shown and shareable results.

About Power Plant Heat Rate Calculator

Heat rate is fuel energy input per unit of electrical output, in kilojoules per kilowatt-hour. It is the reciprocal of efficiency: efficiency = 3600 / heat rate. Net heat rate uses output after station auxiliaries, which consume 5-8% of gross output in a coal plant and 2-3% in a gas turbine plant.

Formulas

Heat rate

Heat rate (kJ/kWh) = fuel energy input / net electrical output

Efficiency

Efficiency % = 3600 x 100 / heat rate

Worked example

With the default values below, Power Plant Heat Rate Calculator returns Net Heat Rate of 9,042.6. Change any input above and every figure here is recalculated in your browser.

Inputs used

Fuel Energy Inputminimum 0 GJ/hour: 8,500 GJ/hour
Net Electrical Outputminimum 0 MW: 1,000 MW
Auxiliary Consumptionaccepts 0–40 %: 6 %
Fuel Costminimum 0 per GJ: 8 per GJ

Results

Net Heat Rate: 9,042.6
Thermal Efficiency: 39.812%
Net Output After Auxiliaries: 940.00
Fuel Cost Per MWh: $72.340

Step by step

1Values used
2Heat rate
3Efficiency
4Net Heat Rate= 9,042.6
5Thermal Efficiency= 39.812
6Net Output After Auxiliaries= 940.00
7Fuel Cost Per MWh= 72.340

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

What heat rates are typical?

About 9500-11,000 kJ/kWh for a subcritical coal unit (33-38%), 8000-8500 for supercritical, and 6000-6600 for a modern combined cycle gas plant (55-60%).

Why report net rather than gross heat rate?

Only net output reaches the grid and earns revenue. A plant with efficient auxiliaries has a better net heat rate even at the same boiler and turbine performance.