Cogeneration (Combined Heat and Power or CHP) is the simultaneous production of electricity and heat, both of which are used. The central and most fundamental principle of cogeneration is that, in order to maximise the many benefits that arise from it, systems should be based according to the heat demand of the application. This can be an individual building, an industrial factory or a town/city served by district heat/cooling. Through the utilisation of the heat, the efficiency of cogeneration plant can reach 90% or more. Cogeneration therefore offers energy savings ranging between 15-40% when compared against the supply of electricity and heat from conventional power stations and boilers:

Typical Cogeneration Scheme:

Tyical conventional power generation scheme:

Cogeneration optimises the energy supply to all types of consumers with the following benefits to both users and society at large:

• Increased efficiency of energy conversion and use. Cogeneration is the most effective and efficient form of power generation
• Lower emissions to the environment, in particular of CO2, the main greenhouse gas. Cogeneration is the single biggest solution to the Kyoto targets
• Large cost savings, providing additional competitiveness for industrial and commercial users, and offering affordable heat for domestic users
• An opportunity to move towards more decentralised forms of electricity generation, where plant is designed to meet the needs of local consumers, providing high efficiency, avoiding transmission losses and increasing flexibility in system use. This will particularly be the case if natural gas is the energy carrier
• Improved local and general security of supply - local generation, through cogeneration, can reduce the risk that consumers are left without supplies of electricity and/or heating. In addition, the reduced fuel need which cogeneration provides reduces the import dependency - a key challenge for Europe's energy future
• An opportunity to increase the diversity of generation plant, and provide competition in generation. Cogeneration provides one of the most important vehicles for promoting liberalisation in energy markets
• Increased employment - a number of studies have now concluded that the development of CHP systems is a generator of jobs.

More in-depth information on cogeneration is provided in the following publications:

Cogeneration Fact Sheet
A two-page overview developed for UNEP by COGEN Europe (269 Kb)

EDUCOGEN - An educational tool for cogeneration, second edition (2001)
Developed through the EDUCOGEN project. A comprehensive overview about cogeneration principles, technologies, applications, economies, etc. on 176 pages
4.0 Mb
2.1 Mb

A Guide to Cogeneration (2001)
Developed through the EDUCOGEN project. This Guide is designed to explain the principles and applications of cogeneration and to help policymakers and other professionals understand this technology.
1.6 Mb
211 Kb