Computes a transparent planning estimate for space-heating demand. The method is not DIN, VDI, GEG or PHPP and must not be used as regulatory proof. It combines transmission heat loss from each envelope component, ventilation heat loss from heated volume and air changes, monthly heating degree days from the nearest DWD 1991-2020 temperature-normal station, stated internal gains and optional domestic hot water.

Uses rated electrical power, food mass, start and target temperature, specific heat and an explicit efficiency range supplied by the caller. Optional vessel heat, evaporation and a caller-defined hold phase can be included. It contains no recipes, recipe text, food-specific cooking claims or hidden food database; the output separates the thermodynamic lower bound from the practical range and is not a food-safety clearance.