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Can Coal Go Green?

 

Coal is indispensable. No other energy source is as cheap and provides such high power output. Historically, coal has always been one of the most important elements to development. It is essential for electricity generators that provide the industrialized world with the energy it needs to succeed. Power creation from burning coal fueled the fire behind the industrial revolution. It has developed all major economies and their respective countries. It is a very established practice that has strong bureaucratic and cultural ties. Coal is easy and coal is cheap, but coal is not green. As David G. Victor and Richard K. Morse skillfully explain in “Living with Coal: Climate Policy’s Most Inconvenient Truth,” coal has always been the dirtiest energy source. The combustion of coal produces high quantities of carbon dioxide, one of the leading greenhouse gases responsible for global warming. This major issue is in addition to local air and water pollution. It is even more inconvenient that coal can be found almost anywhere in world, its global distribution is very even. Almost every country can easily access it.

Accessing Coal

The methods to access coal do not create a greener reputation for the material. Historically coal was mined for by chipping away and into mountains. This put miners in incredibly dangerous situations that had long term side effects. Today, the most common way to extract coal is through mountaintop removal. In this process, the peak of a mountain is blown up using an explosive. The detached rock is then harvested for coal. To read more about the transformation of mining techniques click here. Although modern mining is less dangerous for the workers, it is detrimental on the environment. It causes problems below the mountain as many trees are uprooted for the process, making the lowlands more susceptible to mudslides. The coal is also more likely to pollute the water supply as it is not contained inside of the mountain.

 Image 1. A mountaintop removal sight.

One of the largest questions is what to do with a quarry once it has been emptied of the coal. Some have thought of possible green solutions, such as turning the area into farmland or planting various trees on it to reforest that area. Although these are valiant efforts, there has not been proof of any great success in reforming these regions, nor are many governments keen on funding the efforts.

No matter how awful coal is for the environment, it is so essential, that the consumption of coal across the globe has only continued to increase. According to the International Energy Agency, the largest consumer of coal is China at 42% of the total coal consumed in the world. The United States consumes 16%, the same amount as the rest of the world’s coal consumption combined. The USA used coal to promote its development and build one of the greatest economies in the world, which is exactly what China is doing with its coal consumption now. China is trying to develop rapidly. The foundation of their ever growing economy lies on the back of the black, gritty surface of coal. Renewable energy options are simply not affordable nor powerful enough to compete in the commercial energy market. That is why coal must try to go green.

Green Coal Technologies

The consumption of coal is only estimated to increase according to the International Energy Agency, and it is barely sustainable at its current levels. There will be no green future is coal production and management does not change. This is where there have been many developments. MIT is one of the leading research facilities on carbon capture and sequestration technologies. To learn more about their program click here. According to the Global Carbon Capture and Storage Institute (GCCSI), these technologies involve capturing the carbon dioxide that is produced when burning coal and pumping it into various deep rock formations or the ocean. The carbon dioxide is compressed for transportation through a pipeline to the storage site.

Image 2. the basics behind carbon capture and storage.

Carbon is captured in three main ways, pre-combustion, post-combustion, and oxyfuel with post-combustion. Pre-combustion converts fuel into a mixture of hydrogen and carbon dioxide. The hydrogen can then be burned without releasing the carbon, and thus the carbon dioxide is separated, compressed, and transported. This method is hard to apply to pre-existing power stations, unlike post-combustion.

Post-combustion operates by separating the carbon dioxide from the mixture of combustion exhaust gases. The carbon dioxide is then captured using a liquid solvent.

The oxyfuel and post-combustion method uses pure carbon as the second reactant for the combustion of coal. This produces exhausts that are mainly water vapor and some carbon dioxide, which is then separated using the post-combustion method mentioned above. For more detailed information on the technology please see the GCCSI website.

Many of these methods are becoming common in new power plants as they often help companies make money by selling the carbon dioxide collected and through government funding. Although these methods are critical in helping to turn carbon green they have their downfalls. Pumping carbon dioxide into the ocean can change the pH levels of the water. These levels are directly correlated with the health of the underwater ecosystem as many of the plants and animals can not withstand a more basic or acidic environment. It is also unclear as to how pumping carbon dioxide into geological formations will impact the environment in that region. So, many people are skeptical of carbon capture methods.

Will it be enough?

Even with these developments and the continued growth of renewable, nuclear, and geothermal energy options, coal continues to be the biggest producer of both energy and pollutants. There is not much that can be done to tackle the giant that is the coal business, it is central to many jobs, economies, and culture. Tackling the giant means encouraging people to embrace greener lifestyles overall as there most likely would be something lost with the end of coal. However, the question comes down to if coal can ever be green. Can coal be a part of creating a more sustainable global society?  Victor and Morse both believe that a coal free future in impossible, at least in the near future. By the time that renewables really take off as a viable, industrial energy option, it will be too late. The only options are to continue to promote greener coal practices such that carbon dioxide pollution will decrease even as the consumption of coal increases or to prove to governments that a growing economy can be achieved without the use of coal.

To read more about coal, its impact and evolution please see the Victor and Morse article, “Living with Coal: Climate Policy’s Most Inconvenient Truth” here.

Editor: Daryn Dever