Megajoules (MJ) to Kilowatt-hours (kW·h) Conversion
Megajoules
The megajoule (MJ) is a unit of energy equal to exactly 1,000,000 joules (10⁶ J). It is used in energy policy, engineering, and physics for large-scale energy quantities. One kilowatt-hour (kWh) equals exactly 3.6 MJ — the conversion fundamental to understanding electricity bills. A litre of petrol contains approximately 34 MJ of chemical energy. The explosive yield of conventional explosives is sometimes expressed in megajoules.
Kilowatt-hours
The kilowatt-hour (kW·h) is a unit of energy equal to exactly 3,600,000 joules (3.6 MJ), defined as the energy consumed by a one-kilowatt device operating for one hour. It is the standard unit on electricity bills worldwide. A typical European household consumes approximately 3,500 kWh per year. One kWh powers a 100-watt bulb for 10 hours, charges an electric vehicle by approximately 5–8 km of driving range, or powers the average laptop for about 10 hours.
| Megajoules (MJ) | Kilowatt-hours (kW·h) |
|---|---|
| 0.1 MJ | 0.027777777777778 kW·h |
| 1 MJ | 0.27777777777778 kW·h |
| 2 MJ | 0.55555555555556 kW·h |
| 3 MJ | 0.83333333333333 kW·h |
| 5 MJ | 1.3888888888889 kW·h |
| 10 MJ | 2.7777777777778 kW·h |
| 20 MJ | 5.5555555555556 kW·h |
| 30 MJ | 8.3333333333333 kW·h |
| 50 MJ | 13.888888888889 kW·h |
| 100 MJ | 27.777777777778 kW·h |
| 1000 MJ | 277.77777777778 kW·h |
Frequently Asked Questions (FAQ)
How many kilowatt-hours are in 1 megajoules?
1 megajoules (MJ) is exactly 0.277778 kilowatt-hours (kW·h).
How do I convert megajoules to kilowatt-hours?
Multiply the value in megajoules by 0.277778 to get the result in kilowatt-hours. Or use the converter above — type any number and see the result instantly.