United Kingdom is the windiest country in Europe, so much so that we could power our country several times over. 
How CHP Works
CHP is a complex process involving the conversion and transition of energy.
When electricity is being generated the by-product heat is stored in a heat recovery boiler and can be used to raise steam, to provide water heating, while the electricity can be used for the electrical needs of a home or business. To achieve this, a CHP plant needs a fuel source, such as natural gas or biomass and generally consists of a gas turbine, an engine or a steam turbine to drive an alternator which produces the electricity.
Below is an illustration of a typical small scale CHP plant unit. This shows a number of elements which make up a CHP system, these include:
- Stirling engine or similar
- Generator - produces electricity
- Heat Recovery system - obtain useable heat from the engine
- Cooling system - dissipate heat
- Combustion and Ventilation air systems - provide fresh air and remove exhaust air.
- Control System - maintain a safe and efficient operation
- Enclosure - Provide a physical barrier and form of protection
Fuel Supply/ Generator
Firstly, CHP requires a source of fuel, there are two main types, these being natural gas and oil, in the form of diesal or gas oil.
For the process of combustion to occur, there needs to be an method of ignition, attainable through compression or a spark to engage the stirling engine.
After ignition, the stirling engine, will in turn activate the Generator.
Generators create electricity by moving an electrical conductor through an magnetic field.
These may either may:
- Synchronous - rotate at a fixed speed, and mantains its own frequency standard
- Asynchronous - cannot maintain a frequency instead relying on the mains supply
Heat Recovery and Cooling System
Overall thermal efficiency may be as high as 90% for CHP schemes using this heat recovery technique. Heat produced from the Engine is transferred through a process of heat exchange via conduction and convection to the water pipes. Exhaust gases are removed through a seperate outlet.