Patent ID: 7240504

Claim:
A cogeneration system comprising: an engine, which drives a generator to generate electricity; a cooling/heating unit, which comprises at least one compressor, a four-way valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger, to establish a heat pump type refrigerant cycle; an exhaust heat consuming heating unit to supply heat of exhaust gas discharged from the engine to a heat exchanging zone of the indoor heat exchanger of the cooling/heating unit, and thus, to heat a confined space; a cooling water heat exchanger to recover heat of a cooling water passing through the engine during a heating operation of the cooling/heating unit; and a refrigerant pre-heating heat exchanger located between the cooling water heat exchanger and a refrigerant line connected to the suction section of the compressor, to transfer the heat recovered by the cooling water heat exchanger to a refrigerant in the refrigerant line at the suction section of the compressor, thereby preventing the refrigerant from being overheated.