Cogeneration of heat and power

Cogeneration is a technique where the production of heat and electricity occurs in a single process or power plant. A modern fossil-fuel power plant transforms about half the primary energy content of its fuel into electricity and rejects the rest as ‘waste’ heat. Cogeneration or Combined Heat and Power (CHP), uses a part of that heat to satisfy a heat demand which would otherwise require energy from another source,usually a fuel. The heat is often in the form of hot exhaust gases, steam or hot water. CHP thus improves the overall efficiency of fuel utilisation and saves on primary energy in comparison to the conventional separate production of power and heat.