Heat and electric power supply system and operation method thereof

A heat and electric power supply system which comprises a regenerative gas turbine and an adsorption refrigerator recovering exhaust heat of exhaust gas from the gas turbine is provided with an inlet air cooling equipment including a spray device for spraying cold water form the adsorption refrigerator into an air-intake port of the regenerative gas turbine and a humidifier effecting humidification by hot water injection from the refirigerator into a compressor delivery port of the regenerative gas turbine. The cooling by cold water and humidification by hot water injection are effected according to operational conditions.