System Performance Calculators

Calculate system efficiency (COP/EER) and total environmental impact (TEWI) for refrigeration, air conditioning, and heat pump systems.

2 Calculators EN 14511 / EN 378 Free to Use

COP / EER Calculator

EN 14511

Calculate the coefficient of performance (COP) and energy efficiency ratio (EER) for a cooling or heating system. COP = Output / Input. EER converts COP to BTU/Wh.

TEWI Calculator

EN 378 / BS EN 378

Calculate the Total Equivalent Warming Impact (TEWI) of a refrigeration system. TEWI combines direct emissions (refrigerant leakage) and indirect emissions (energy consumption) over the system lifetime.

UK average: 0.233 kg CO2/kWh (2023)