Micro-cogeneration, also termed micro combined heat and power (MCHP) or residential cogeneration, is an emerging technology with the potential to provide energy efficiency and environmental benefits by reducing primary energy consumption and associated greenhouse gas emissions. MCHP can help to meet a number of energy and social policy aims. These are the reduction of greenhouse gas emissions from energy supply, increased decentralization of energy supply, improved energy security, possible avoidance of investment in and energy losses from electricity transmission and distribution networks, and potentially reduced energy cost to consumers. Micro-cogeneration systems have the potential to reduce energy demands of the residential sector for space heating, domestic hot water heating, and electricity. The reduced greenhouse gas emissions and reduced reliance upon central electrical generation, transmission, and distribution systems are the possible benefits. Also in the present paper, a comparison has been made between the MCHP technology and the other ones such as prime mover, electrical and thermal power, efficiency and emissions. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.