Geothermal Heat Pump (COP) Calculator
Estimate the Carnot and realistic coefficient of performance of a geothermal heat pump from source and sink temperatures and a practical efficiency factor.
How to Use the Geothermal Heat Pump (COP) Calculator
- Enter the hot-side (space-heating) supply temperature in °C.
- Enter the cold-side (ground loop) source temperature.
- Enter the practical efficiency as a percentage of Carnot.
- Click Calculate.
Casos de Uso
- •Sizing ground-source heat pumps.
- •Energy audits.
- •Teaching the second law of thermodynamics.
Fórmula
COPcarnot = T_hot / (T_hot − T_cold) with temperatures in Kelvin. Real COP = COPcarnot × practical efficiency.
Perguntas Frequentes
Why is real COP lower than Carnot?
The Carnot value is the thermodynamic limit. Real compressors, heat exchangers, defrost cycles and refrigerant pressure drop cost typically 35–55% of that maximum.
What practical percentage should I use?
Modern brine-to-water heat pumps reach about 45–55% of Carnot at the seasonal operating point. Older units and large ΔT conditions drop to 30–40%.
Is COP the same as EER?
COP is used for heating, EER/SEER for cooling. They use the same temperature-difference logic but different reference states.