Coal: The Inside Story
Coal has been the first fuel in history. It was what Thomas Edison chose to fuel his power plants, which were spreading like a plague throughout the country. Even now it is the most widely used fuel to generate enough electricity for our growing country. It can also be used in many ways, from generating electricity or providing fuel to burn for a barbecue, to art. But what is the real secret to coal? Coal has advantages to using it, but also very detrimental effects that damage the ecosystem and the planet.
But how does electricity get generated out of plain black rocks? Energy can be changed into different forms. Fuels must go through a couple of energy transformations to get their chemical energy converted into electricity. Fossil fuels have stored energy that can be released through combustion, or burning. This releases the chemical energy in the form of thermal energy, which boils water into water vapor, and that spins a generator, creating electricity. Then the electricity is passed through a transformer to adjust the power, and finally, it is brought to homes and offices through high-tension power lines. This same process is used in many other fuels. In fact, every mechanism for converting energy from an electrical resource like the sun, wind, water, natural gas, or biomass fuels involves turning a generator to produce electricity (except for photovoltaic solar cells, which use balanced ionized silicon to get destabilized by photons and create an electric current). But how does the coal even get to the power plant?
There are four types of coal: bituminous coal, anthracite coal, sub-bituminous coal, and lignite coal. Bituminous coal (C137H97O9NS) is the raw, soft form of anthracite coal that is mined from the ground. Anthracite coal (C240H90O4NS) is a harder coal that contains much more carbon than bituminous coal. Sub-bituminous coal is softer than bituminous coal because it contains more water, and lignite yet more, making it the softest kind of coal. Anthracite is used in coal power plants because the other types contain water and therefore do not burn very well. It also does not emit much smoke when it burns. When the coal is mined, it is arranged in layers of rock called seams. There are many ways to mine for the coal seams. One technique is called strip mining, where layers of rock are removed above the seam. Another method is contour mining, removing earth from above a seam following the contours of a slope. Mountaintop mining involves removing mountaintops to expose coal seams. However, usually coal seams are deep underground, requiring the use of underground mines. This is more dangerous to miners than surface mining, but both types damage the ecosystem. But why has coal always been the fuel of choice?
There are a few advantages to using coal in power plants. Coal contains a lot of stored energy per unit volume because of its complex molecules. It is also not very hard to transport and it is a cheap fuel to use and set up. For this reason, coal has been the most popular fuel since its discovery. However, it is not like it is a perfect fuel. Coal also has many disadvantages. Its mining damages ecosystems, especially surface mining, and underground mining is dangerous due to the ash and toxic gases. Therefore, most coal miners get “black lung disease” from the ash particles and many die from the noxious gases. The burning of coal also causes air pollution, dumping ash into the atmosphere. Even fuels that do not produce ash when they burn still give off carbon dioxide and water vapor, two of the greenhouse gases. The carbon dioxide in the atmosphere is rapidly increasing, making the planet warm up, and this can cause many drastic changes in the global climate and melt the Arctic ice, which raises sea levels. Most of all, coal is a nonrenewable resource. Despite Earth being abundant in coal, someday it will run out, and it will take millions of years to form new coal, because the animals have to decay and have their carbon compressed into coal form, which takes quite a long time. The coal in a local coal-fired power plant may well have been the remains of a dinosaur. So if coal is not a practical fuel to use long-term, what other options are available?
In reality, no fuel is perfect. There are problems with using any fuel, including coal, despite it also having some advantages. However, coal cannot be used forever. The Earth only has a finite supply of coal, and as humans’ need for electricity increases, coal supplies will start decreasing faster. People must start to use renewable resources, cleaner forms of energy that do not run out (at least not for a very long time). That is the only solution to the energy crisis. Nature provides many resources that do not need to be mined. A practical way to use the available fuels will once again allow the Earth to stabilize and return to how it was before the Industrial Revolution, maybe even better. The planet and its life are very delicate, and people must choose fuels wisely.