Pros and cons of coal-fired power plants

  • By Khin Maung Myint

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Whenever a coal-fired power plant project was planned to be implemented, there would always be opposition in some countries. The non-governmental organizations (NGOs) and enviromental activists will demonstrate vehementally against their constructions. Such incidents are common in our neighbouring country since a long time ago. That trend had now crept into our society too. We had been witnessing the demonstrations and activities to oppose the constructions of coal-fired power plants becoming popular in our country in the recent years.
I have been an ardent advocate for the control of climate change and had persistently written in many of my articles related to the climate change, to substitude the fossil fuels, including coal, with renewable or green energies, such as: solar, wind, hydro and geothermal energies. These fossil fuels are great emitters of CO2 and other gases that constitute the greenhouse gases, which contribute to the global warming–the root cause of the climate change.
However, after coming across a very interesting piece of information on the Internet about how the greenhouse gas emission of coal-fired power plants can be reduced to the near-zero emission level by the latest technologies, my opinion of the dangers of the coal-fired power plants is somewhat changed. I started to weigh the pros and cons of the use of coal-fired power plants. If that claim made by some experts should prove to be true, it would be really an encouraging breakthrough that would benefit, especially the developing countries including ours’, greatly. To appreciate which aspect outweighs the other, it would be necessary to know what are the pros and cons of coal-fired power plants.
Coal-fired power plants are a type of power plant that make use of the combustion of coal in order to generate electricity. Records show that their use provides around 40% of the world’s electricity and are primarily found in developing countries. Countries such as South Africa use coal for 94% of their electricity and China and India use coal for 70-75% of their electricity needs. Among them, the amount of coal China uses far exceeds most other countries. We all know that electricity is the most essential commodity and a great driving force for developments, it helps to increase quality of life and reduce poverty in those regions, where it is available.. Though the use of coal provides access to electricity to those who previously didn’t have it, the adverse effect is, it produces large quantities of different pollutants, which reduce the air quality and adversely impact on the climate.
Here, it would be necessary to discuss the conversion of the coal to electricity. The coals must be transported to the site of the power plant, either by train or ship. Once there the coals are unloaded. They are then pulverized into a fine powder by a large grinder. This ensures nearly complete burning of the coal in order to maximize the heat given off and to minimize pollutants.The pulverized coal is then fed to a boiler, where combustion occurs and this provides heat to boil the water in the boiler, producing steam. The steam then travels through a turbine, causing it to rotate extremely fast which in turn spins a generator, producing electricity. The electricity can then be input to the electrical grid for use by the society. Since they require plenty of water to be circulated in this cycle, coal power plants need to be located near a body of water.
Large quantities of water are often needed to remove impurities from coal, in the process known as coal washing. For instance, in China, around one-fifth of the water used in the coal industry is used for this process. This process helps to increase the thermal efficiencies to a higher level and reduce air pollution, as it eliminates around 50% of the ash content in the coal, resulting in the less emission of greenhouse gases.
When power plants remove water from the environment, fish and other aquatic life can be affected, along with animals relying on these sources. Pollutants also build up in the water that power plants use, so if this water is discharged back into the environment it can potentially harm wildlife there. Thus the discharging of water from the power plants and coal washing requires monitoring and regulation. When the water in our rivers, lakes, and oceans becomes polluted; it can endanger wildlife, make our drinking water unsafe, and threaten the waters where we swim and fish.
Also, the use of coal have many associated environmental impacts on the local ecosystem. It is universally accepted that the coals are packed with carbon and other matters that become great polluters when burned. The burning of coal releases many pollutants – oxides of nitrogen (NOx) and sulfur (SOx)- and particulate matter. They also emit greenhouse gases, such as carbon dioxide (CO2) and methane (CH4), which are known to contribute to global warming and climate change. To help reduce the emission of these pollutants, power plants require technology to reduce the output of these harmful molecules.
The above mentioned adverse effects of the coal-fired power plants are the disadvantages, but there are also many significant advantages. As for the plus side or the pros, it is undeniable that they made electricity readily accessible for those who never had that opportunity before. Electricity is the indispensible driving force for the development and the economy of a country, which would help enhance the quality of life and reduce poverty. With the outmoded coal powered plants, the cons may outweigh the pros and strengthen the opponents’ stand to oppose the coal power plants. However, if we could introduce the modern and advanced types of coal-fired power plants, which are eco friendly, these cons would be cancelled out by the pros.
Today, researchers had found that improving efficiency can increase the amount of energy that can be extracted from a single unit of coal. A one percentage point improvement in the efficiency of a conventional pulverized coal combustion plant results in a 2-3% reduction in CO2 emissions. If the current average global efficiency rate of coal-fired power plants could be raised from 33% to 40% by deploying more advanced technology it would cut two gigatonnes of CO2 emissions, which is equivalent to India’s annual CO2 emissions. Improving efficiency increases the amount of energy that can be extracted from a single unit of coal.
Deploying high efficiency, low emission coal-fired power plants is a key first step along a pathway to near-zero emissions from coal with carbon capture, use and storage. This high efficiency, low emission technologies or the “clean technologies” are commercially available now and, if deployed, can reduce greenhouse gas emissions from the entire power sector by around 20%, while allowing affordable energy for economic development and poverty reduction. In addition to the significant benefits from reduced CO2 emissions, these modern high efficiency plants have significantly reduced emissions of nitrogen oxides, sulfur dioxide and particulate matter. Besides the climatic benefits of reduced CO2 emissions, reduction in these pollutants is of additional importance at the local and regional level in addressing the air quality and the related health concerns.
In conclusion, I would like to suggest that we should study our neighbour, Laos, which is rapidly developing. To my knowledge, that landlocked small nation, without much natural resources like our country, had developed in leaps and bounds in a very short time. What could have propelled them ahead so fast? Well, in my opinion, though they already have numerous hydro electricity plants producing more electricity than their needs, they built a modern coal-fired power plant in 2015 to augment the electrical power generation. It comprises three 626 Megawatts generators—quite a large one too. It was a result of high demand from Thailand, where there are shortages as they are unable to build coal-fired power plants due to strong oppositions from the NGOs and environmental activists. Though they lacked the natural resources, Laos had made up for that handicap by investing in the electricity exporting business, which supplemented their economic growth significantly. Opponents of the coal-fired power plants should realize that if that power plant in Laos, which utilizes the “clean technologies” is alright for them, it would be okay for us too.

References:—

World Coal Association website,
Energy Education website,
Wikipedia.

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