Abstract: An electrical and thermal energy supply system for buildings is disclosed wherein electricity is generated by an engine driving a generator either inside or in close proximity to the building. Heat generated by the engine is recovered and supplied to the building. The electrical generating system is activated on demand for electricity from within the building. Optionally, the output of the generator may be used to electrically heat water or air, or both, to supplement the heat recovered from the operation of the engine. Additionally, a battery-inverter, chargeable by the generator, may be included to reduce the duty cycle of the engine. A wind powered generator may be further added to charge the battery and conserve fuel, especially in warmer time periods.