How the calculation works
Enter only gas consumption and charges that would disappear. If gas stays connected for heating, do not count its fixed charges as savings. Use additional electricity consumption from appliance specifications or measured estimates, not a direct Smc-to-kWh shortcut. Enter an all-in variable electricity rate and only additional fixed charges. Results assume constant prices, excluding financing, inflation, grants and future replacements. Simple payback is not a technical suitability assessment.
Annual saving (negative = extra cost) = Annual gas cost avoided − Additional annual electricity cost Additional annual electricity cost = Additional electricity per year (kWh) × All-in variable electricity cost (€/kWh) + Additional electricity fixed charges per year (€) Simple payback (years) = Upfront investment / Annual saving (negative = extra cost) (> 0) Net saving over selected years = Comparison period (years) × Annual saving (negative = extra cost) − Upfront investment