kWh to GJ converter
1 GJ is 277.8 kWh, so 1 kWh is 0.0036 GJ. Type in either box; handy for heat network bills.
1 kWh = 0.0036 GJ (1 GJ = 277.8 kWh)
Why 277.8?
A gigajoule is a billion joules. A kWh is 3.6 million joules, by definition. So one GJ holds 1,000,000,000 ÷ 3,600,000 = 277.8 kWh (rounded; the real figure is 277.777…), and one kWh is exactly 0.0036 GJ.
Dutch heat networks (district heating) bill their heat in GJ, and so do district heating companies in countries like Denmark and Poland. Your electricity bill stays in kWh, which makes the two hard to compare until you convert.
On the napkin
A Dutch home uses about 2,500 kWh of grid electricity a year. That's 2,500 × 0.0036 = 9 GJ.
Say a heat network charges €35 per GJ. Divide by 277.8 and that's €0.126, or 12.6 cents, per kWh of heat, before the fixed annual charge most heat networks add. Now you can put it next to the price on your electricity bill.
Common values
| GJ | kWh |
|---|---|
| 1 | 277.8 |
| 10 | 2,778 |
| 40 | 11,110 |
| 100 | 27,780 |
| kWh | GJ |
|---|---|
| 1 | 0.0036 |
| 1,000 | 3.6 |
| 2,500 | 9 |
| 10,000 | 36 |
Need another unit?
The full energy converter shows any amount in every energy and power unit at once, from joules to kilowatt-hours to cups of tea.
Want to compare your heat bill with a heat pump?
The free spreadsheet works it out from the prices on your own bill. It comes by email, together with the unit converter as a sheet. One short email a month at most.
Send me the spreadsheetsSources: 1 GJ = 10⁹ J and 1 kWh = 3.6 MJ, both by definition (SI). Dutch home electricity: CBS StatLine 81528NED, 2023 (provisional). The €35 per GJ is an example, not a quoted tariff.
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