How does coal generate electricity?

Coal is a combustible black sedimentary rock, that is primarily made from plants that died millions of years ago and decayed into peat, which was then transformed over time. Coal is primarily used for fuel purposes, and although it has been in the historical record for a long time, coal became a major fuel material during the Industrial Revolution, when coal began to be used in large quantities with the invention of the steam engine. Coal supplies about a quarter of the world’s primary energy and over a third of it is used in producing electricity.

Coal is also divided into many types, but we are going to talk only about steam coal, also known as thermal coal, which is used in power stations to generate electricity. This is generally coal used for thermal power generation. Any coal used to generate power for the purpose of power generation, locomotive propulsion, boiler combustion, etc. belongs to steam coal. The requirements for calorific value, volatile matter, and ash content of power coal are not as high as those for chemical coal (such as coking coal for steel making). However, from the consideration of the economic benefits of the power process, power coal should also have certain quality requirements.

And now we going to talk about how is coal converted to electricity. So firstly, we use steam coal milled into fine powder, turning coal into powder can increase the surface area and allow the coal to burn faster. Then mixed with hot air and blown into the firebox of the boiler. Burning in suspension, the coal/air mixture provides the most complete combustion and maximum heat possible. The hot gases and thermal energy made from burning the coal will be generated to convert the water in the boiler’s lined tubes into steam, which then enters the turbine from the high-pressure steam, whose immense pressure pushes a series of giant turbine blades to turn the turbine shaft. The turbine shaft is connected to the shaft of a generator, where magnets rotate inside coils to produce electricity. After work is completed in the turbine, steam is drawn into the condenser and millions of gallons of cold water from a nearby source are pumped into a network of piping that runs through the condenser. The cold water in the piping converts the steam back into water that can be reused again and again in the plant.

The use of coal damages the environment, and it is the largest anthropogenic source of carbon dioxide affecting climate change. 40 billion tons of carbon dioxide were emitted by burning coal in 2020, which is 40% of the total fossil fuel emissions and over 25% of total global greenhouse gas emissions, many countries now have reduced their use of coal power, and also we now got Paris Agreement and Glasgow Climate Pact to helping the country who mainly using coal as largest consumer to reduce the emissions that has been made.

https://en.wikipedia.org/wiki/Coal

https://en.wikipedia.org/wiki/Coal-fired_power_station

https://www.futurecoal.org/coal-facts/coal-electricity/

https://www.amupower.co.ke/coal-electricity.html

This article is a part of the class

“751447 SEM IN CUR ECON PROB”

supervised by

Asst. Prof. Napon Hongsakulvasu

Faculty of Economics,

Chiang Mai University

This article was written by Chuyi Luo 641615501