Work out a heat pump's Seasonal Coefficient Of Performance (SCOP, per EN 14825) — its season-average heating efficiency. Mode A weights the four declared part-load COP test points by the average-climate reference bin hours; Mode B is the simple seasonal heat-out ÷ electricity-in ratio. Then map SCOP to an ErP energy-label class and estimate running cost against a resistive heater and a gas boiler. Figures are planning estimates for the EN 14825 "average" climate zone.