Co-generation
Q. Explain the need of co-generation plants help energy conservation
- Co-generation is the system which produces two forms of energy from one fuel. One of the forms of energy must be heat and other may be electricity or mechanical.
- Figure represents a typical co-generation thermal power plant in such plants, coal in the pulverized form is burnt in the boiler, which generates high pressure steam. This is applied to steam-turbine to produce mechanical power, as turbine is connected mechanically to electric generator, it converts mechanical energy into electrical energy.
- The exhaust low pressure steam from turbine is generally condensed to water, which goes back to boiler
- Also the flue gases from boiler containing heat energy are exposed to atmosphere directly.
- Hence, the efficiency of conventional power plant is low and may be about 30-35%.
- The low pressure steam (exhaust steam from turbine) has large amount of heat, which is lost in condensing, if utilized in either preheating of feed water or used for other factories, great energy saving can be achieved.
- At the same time flue gases from boiler going to Chimney can be used to heat other products of industry or houses or passes through economizer to heat the feed water to boiler.
- The efficiency can be greatly increased. Such type of plants are termed as co-generation plants. It is estimated that nearly 25000 MW of additional power generation is possible by Co-generation in India.
- Hence, it becomes necessary to install co-generation plants where it is possible.