Heat Energy Calculator
Energy needed to change the temperature of a mass, in megajoules and kilowatt-hours.
Results
Heat
28.2555
MJ
Energy
7.8488
kWh
Temperature change
45.00
K
Heat capacity of the whole thing
627.9000
kJ/K
Energy in kilojoules
28,255.5000
kJ
What this tool does
The energy needed depends on how much material there is, what it is made of and how far you want to move its temperature. The default specific heat is that of water, 4186 J per kilogram per kelvin — unusually high, which is why water is such a good heat store.
Formula
Q = m × c × ΔT
Variables
| Symbol | Meaning | Unit |
|---|---|---|
m | Mass | kg |
c | Specific heat capacity | J/(kg·K) |
t1 | Initial temperature | °C |
t2 | Final temperature | °C |
Q | Heat | MJ |
QW | Energy | kWh |
DT | Temperature change | K |
HC | Heat capacity of the whole thing | kJ/K |
QK | Energy in kilojoules | kJ |
Worked example
- Mass150 kg
- Specific heat capacity4186 J/(kg·K)
- Initial temperature15 °C
- Final temperature60 °C
- Heat28.2555 MJ
- Energy7.8488 kWh
- Temperature change45.00 K
- Heat capacity of the whole thing627.9000 kJ/K
- Energy in kilojoules28,255.5000 kJ
Limitations
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.