2 kWh to MJ — 2 kilowatt-hours in megajoules
Exact 2 × 3.6 = 7.2
2 kilowatt-hours in other units
| Joules | 7,200,000 | J |
|---|---|---|
| Kilojoules | 7,200 | kJ |
| Megajoules | 7.2 | MJ |
| Watt-hours | 2,000 | Wh |
| Calories | 1,720,841.3 | cal |
| Kilocalories | 1,720.84 | kcal |
| British thermal units | 6,824.28 | BTU |
| Therms | 0.06824283 | thm |
| Foot-pounds | 5,310,447.47 | ft·lbf |
| Electronvolts | 44,938,865,336,117,492,057,112,576 | eV |
kWh to MJ at a glance
| Kilowatt-hours | Megajoules |
|---|---|
| 1 kWh | 3.6 MJ |
| 2 kWh | 7.2 MJ |
| 3 kWh | 10.8 MJ |
| 5 kWh | 18 MJ |
| 10 kWh | 36 MJ |
| 20 kWh | 72 MJ |
| 25 kWh | 90 MJ |
| 50 kWh | 180 MJ |
| 100 kWh | 360 MJ |
| 250 kWh | 900 MJ |
| 500 kWh | 1,800 MJ |
| 1,000 kWh | 3,600 MJ |
How to convert kilowatt-hours to megajoules
Multiply by 3.6 — one kilowatt-hour is 3.6 megajoules. That factor is exact: it comes from the definition of the units rather than from a measurement, so it will not change and does not need rounding.
Working 2 × 3.6 = 7.2
In words: about seven megajoules.
What these units are
The kilowatt-hour and the megajoule are covered in the energy unit guide, along with every other unit on this page.
Questions
How many megajoules are in a kilowatt-hour?
One kilowatt-hour is 3.6 megajoules. This figure is exact — it comes from the definition of the unit, not a measurement.
What is 2 kilowatt-hours in megajoules?
2 kilowatt-hours is 7.2 megajoules. The working is 2 × 3.6 = 7.2.
Is a food Calorie the same as a calorie?
No — it is a thousand of them. The Calorie on a nutrition label is a kilocalorie, written with a capital C in principle and almost never in practice. A 250 Calorie chocolate bar holds 250,000 physics calories, or about 1,046 kilojoules, which is why European labels quote kJ alongside.
What does a kilowatt-hour actually represent?
One kilowatt drawn for one hour — a 1,000 W heater running for sixty minutes, or a 100 W bulb for ten hours. It is the unit your electricity bill is priced in, and it equals exactly 3.6 million joules.
How much energy is one BTU?
Roughly the heat needed to raise one pound of water by one degree Fahrenheit — about 1,055 joules, or the energy in a single kitchen match. Air conditioners are rated in BTU per hour, where a 12,000 BTU/h unit is one "ton" of cooling and draws around 3.5 kW of heat.
Why is the electronvolt so small?
Because it is sized for single particles: it is the energy one electron picks up crossing a one-volt potential difference. At about 1.6 × 10⁻¹⁹ joules it would be absurd for anything larger, which is precisely why particle physics uses it instead of dragging around twenty leading zeros.