Water Heating Energy Calculator

The amount of energy needed to heat water is affected by the amount of water, the change in temperature, and the specific heat capacity of water, which is constant. If you want to calculate, for example, how much energy it takes to heat 50 liters of water from a temperature of 10 °C to boiling, it is calculated as follows:
Specific heat capacity of water c = 4.19 kJ / kg °C (i.e. one kilogram of water binds 4.19 kJ of energy when heating one temperature degree)
Mass of water = 50 kg
Temperature change = 90 °C
These can be used to calculate the amount of energy as follows:
E = c · m · ΔT = 4,19 kJ / kg °C ·  50 kg ·  90 °C = 18855 kJ
Since one Wh is 3600 joules, the result can be converted to the more familiar form of kilowatt-hours (kWh) by dividing the result by 3600:
18855 / 3600 = 5,2375 kWh
Heating the water therefore requires slightly more than five kilowatt hours of energy. Please note that efficiency, heat losses, etc. are not taken into account here. The actual energy demand is therefore more or less higher, depending on the equipment and conditions.