Combined Heat and Power (CHP) is the simultaneous production of both electrical and thermal energy. Fundamentally, it is a gas reciprocating engine coupled to an alternator to generate electricity. Heat is recovered from both the engine and exhaust gases and can be utilised to supplement other on-site manufacturing processes requiring heat. PSI can also install smaller low-pressure units. These are ideal for additional in-house electrical generation complementing the demand for both electrical energy and providing domestic hot water.