Heating Power Calculator
Find the heater power needed to warm a batch of liquid, or how long an existing heater takes, from the volume, specific heat and temperature rise.
- Q = m × cp × ΔT = 1,000 × 4.186 × 45 = 188,370 kJ
- P = Q ÷ (η × t) = 58.14 kW
Heat Energy Formula
P = Q ÷ (η × t)
m is mass (kg), cp specific heat (kJ/kg·K; water 4.186, light oils about 2.0), ΔT the temperature rise and η the fraction of heater output that reaches the liquid.
Worked example
1000 L of water from 15 to 60 °C needs 1000 × 4.186 × 45 = 188,370 kJ. At 90 % efficiency in one hour that is 58.1 kW.
Frequently Asked Questions
How many kW to heat 1000 litres of water?
Each 1 °C rise needs 4,186 kJ (1.163 kWh). Heating 1000 L by 45 °C in one hour needs about 52 kW plus losses.
What is specific heat capacity?
The energy needed to raise 1 kg of a material by 1 K. Water has one of the highest values, 4.186 kJ/(kg·K).
Does this work for gases?
Yes, with the gas mass and its cp. For flowing gas use mass flow instead of mass and the result is power directly.
Learn more on the blog
Thermocouple and RTD installation precautions
A practical, field focused guide on instrumentationblog.in that explains the theory behind this calculator and how engineers apply it on real plants.
Read Full Article