COMBINED HEAT AND POWER

Combined Heat and Power (CHP)* is an efficient way to generate electricity and heat simultaneously. Fuels (such as gas, coal, oil, biomass and hydrogen etc) are burnt to release energy which is then harnessed to serve some useful purpose. The most basic form of the released energy is heat (as in a domestic boiler) and this can then be distributed via a heat-exchanger and a circulating fluid to be used for water and space heating. Quite a large proportion of the heat may be wasted through the flue but by careful engineering that too can be used. For example a second heat exchanger could extract more of the heat by partly condensing the hot exhaust gases and that is the principle of a condensing boiler. No electricity is produced by this method and it is therefore not a CHP system but it has the advantage of being highly efficient at 90% or more.
There are several methods by which Combined Heat and Power can be generated and the dual forms of output power explain to a considerable degree why they too can be highly efficient. However, these techniques are inherently more complex and some of the options are more practical than others.

Back to Previous Page