- Calorific Value Definition: The calorific value is defined as the amount of heat produced by the complete combustion of one unit of fuel.
- Units for Solid Fuels: The calorific value of coal is measured in calories per gram or kilocalories per kilogram.
- Units for Liquid Fuels: Liquid fuels, such as diesel, have their calorific value measured in calories per litre or kilocalories per litre.
- Units for Gaseous Fuels: Gaseous fuels have their calorific value measured in calories per cubic metre.
- Examples of Calorific Values: Lignite (5000 kcal/kg), Diesel (11,000 kcal/litre), and Natural gas (560 kcal/m³).
To generate electricity in a steam power plant, we burn fuels like coal, petroleum oil, or gases. These fuels are essential raw materials for producing electricity in thermal power generating plants. The quality of the fuel is crucial, and the calorific value determines this quality. The calorific value of a fuel is defined as the amount of heat produced by the complete combustion of one unit of the fuel. The unit can be weight for solid fuels like coal, and volume for liquid and gaseous fuels.
The calorific value of coal is defined as the amount of heat in calories produced by burning one gram of coal. This value is expressed as calories per gram. Sometimes, it is measured in kilocalories per kilogram, where the coal’s weight is in kilograms and the heat is in kilocalories. For liquid and gaseous fuels, the calorific value is expressed in calories per litre or kilocalories per litre.
Let us look at calorific value of some well known fuels.
- Lignite has a calorific value of 5000 kcal per kg.
- Bituminous coal has a calorific value of 7600 kcal per kg.
- Anthracite coal has a calorific value of 8500 kcal per kg.
- Heavy oil has a calorific value of 11,000 kcal per kg.
- Diesel oil has a calorific value of 11,000 kcal per kg.
- Petrol oil has a calorific value of 11,110 kcal per kg.
- Natural gas has a calorific value of 560 kcal per cubic metres.
- Coal gas has a calorific value of 7600 kcal per cubic metres.
