Coal Energy Definition, Principle, Sources and Uses Explained
Coal energy is non-renewable, carbon-intensive energy from plant-based solid fossil fuels, that is usable for electricity generation and heating. This article discusses coal energy definition, working principle, sources and uses, as outlined below;
-Coal Energy Definition: 5 Ways to Define Coal Energy
Coal Energy Definition: 5 Ways to Define Coal Energy
Coal energy is a type of non-renewable energy that is derived primarily from coal; which is a solid fossil fuel rich in plant-based hydrocarbon and stored bioenergy.
The above states that coal is not one of the renewable energy resources like solar and wind, that are known for their sustainability and compatibility with the ecosystem. Below is an alternative coal energy definition that highlights the sources of coal energy;
Coal energy is a form of energy from photosynthesis that is conserved in plant biomass that has undergone thermal transformation and preservation; and which is extracted by combustion of lignite, bituminous, sub-bituminous coal, and anthracite [3].
As earlier mentioned, coal energy is simply bioenergy that has been conserved when plant remains in swamps and other areas are preserved over very long periods of time.
In the coal energy definition below, some uses of coal energy are listed;
Coal energy is a type of non-renewable energy from solid fossil fuel, that can be used for electricity generation and heating, among other domestic and industrial applications.
Electricity generation is arguably the most prominent use of coal energy; as coal accounts for about one-quarter of all energy resources used to generate electricity in recent years.
Advantages of coal energy are mentioned in the alternative coal energy definition below;
Coal energy is energy that is extracted as heat when coal is burnt as a fuel, and whose advantages include relative low cost, large reserves, versatility, job creation, and integrated utilization.
The term 'integrated utilization' above is used to refer to the fact that coal can be used alongside other energy resources like petroleum, in integrated power plants.
Lastly, the coal energy definition below highlights some disadvantages of coal energy;
Coal energy is a versatile, low-cost type of energy from coal, whose usage is affected by some drawbacks like non-renewable sources, greenhouse emission, air pollution and associated human health problems [2].
How Coal Energy Works
Coal energy works by a three-step process of fuel extraction, combustion, heat capture and conversion.
1). Extraction (in explanation of How Coal Energy Works)
Extraction occurs by mining, during which coal deposits are removed from their locations among sedimentary rocks using simple methods like excavation [1].
Coal gets its energy from plants which comprise most of its mass, as it is formed as a result of the accumulation and burial of plant matter in oxygen-deficient environments like swamps, where these plant remains are transformed by heat without undergoing biodegradation.
Usually, coal does not require any significant form of processing after it is extracted.
The act of mining coal tends to have some unfavorable environmental impacts, especially if it is conducted without a sustainable approach, and with no form of environmental remediation after a mine site is closed.
2). Combustion
Coal is used as an energy source through combustion, whereby the stored energy is released as heat that can be captured and used for various purposes.
The average amount of energy in coal is about 0.9 kWh/pound, although precise energy output in any given scenario depends on the type, source, and grade of coal being used.
3). Heat Capture and Conversion (in explanation of How Coal Energy Works)
In power plants, energy is extracted from coal under controlled conditions of combustion.
This often occurs in a boiler, where the heat from burning coal is used to produce steam [4].
The scenario briefly described above is what may be alternatively referred to as heat capture.
Here, the heat from coal is captured in water, thereby preventing energy waste. In some cases, cogeneration equipment can be integrated into the coal power plant in order to achieve effective energy capture for all heat losses that may occur during the process of steam production.
After coal energy has been captured and steam has been produced, the steam is brought into contact with a turbine, in order to provide pressure and induce rotary motion of the turbine. This is energy conversion, because the heat energy from coal is used to produce mechanical energy that causes the turbine to rotate.
As a result of its rotation, the turbine activates an electric generator to which it is connected, thereby generating electricity.
In few cases where heat production is the aim, no further conversion of energy is required after coal has undergone combustion to release heat.
Sources of Coal Energy
The primary source of coal energy is sunlight, because this is the form of energy that helps plants grow, and which is stored in plant biomass.
It can also be argued that the sources of coal energy include the various types of coal, which are;
1). Anthracite
2). Sub-bituminous coal
3). Bituminous coal
4). Lignite
Uses of Coal Energy
Uses of coal energy are;
1). Electricity generation
2). Domestic heating
3). Steel production and other heat-dependent industrial processes
Conclusion
Coal energy is energy derived from the combustion of coal, and which can be used for heating and power generation.
Coal energy works by;
1. Extraction
2. Combustion
3. Heat Capture and Conversion
Sources of coal energy include the primary source which is sunlight, as well as the various forms of coal like anthracite, lignite sub-bituminous and bituminous coal.
Uses of coal energy are; electricity generation, domestic heating, steel production and other heat-dependent industrial processes.
References
1). Bilim, N.; Kekec, B. (2016). "Fully Mechanized Excavation System in Underground Coal Mining." 2 ND INTERNATIONAL CONFERENCE ON SCIENCE, ECOLOGY AND TECHNOLOGY-2016 (ICONSETE’2016). Available at: https://www.researchgate.net/publication/313636498_Fully_Mechanized_Excavation_System_in_Underground_Coal_Mining. (Accessed 18 January 2023).
2). Gasparotto, J.; Martinello, K. (2020). "Coal as an energy source and its impacts on human health." Energy Geoscience 2(2). Available at: https://doi.org/10.1016/j.engeos.2020.07.003. (Accessed 18 January 2023)..
3). Höök, M. (2013). "Coal and Peat: Global Resources and Future Supply." Available at: https://doi.org/10.1007/978-1-4614-5722-0_9. (Accessed 18 January 2023).
4). Liu, Z.; Liu, S.; Shi, R.; Wang, J.; Xie, M.; Zheng, S. (2020). "A Control Strategy of the Air Flow Rate of Coal-Fired Utility Boilers Based on the Load Demand." ACS Omega. 2020 Nov 25;5(48):31199-31208. Available at: https://doi.org/10.1021/acsomega.0c04585. (Accessed 18 January 2023).
