Ever wondered where your electricity comes from? What are the origins of the invisible force powering your iPhone and allowing you to have YouTube at your constant disposal? Sixty-four percent of American electricity comes from fossil fuels (coal 43%, natural gas 22%, petroleum 1% ). The other 36% comes from nuclear, hydroelectric, and other renewable sources. This means 64% of the charge in your battery comes from these carbon-rich energy sources. I am not here to educate you on how burning fossil fuels creates electricity. I am here to talk about some of the unfortunate byproducts of this relentless burning.
Coal (the number one offender) is formed over many years when heat and pressure decompose organic material like plants. Burning coal releases carbon dioxide, sulfur dioxide, nitrogen oxides, and mercury compounds into the atmosphere. The average emission for coal in the U.S. is-
- 2,248 lbs/MWh of CO2
- 13 lbs/MWh of SO2
- 6lbs/MWh of nitrogen oxides .
For reference, one MWh (Megawatt hour) is equal to the electricity used by 330 homes in one hour.
While the contribution of SO2 and NOx gases may seem small in comparison to CO2, they pack a punch with respect to their affect on our environment. Nitrogen oxides cause smog, which burns lung tissue, and makes people more susceptible to chronic respiratory diseases. Next time you see a smog alert understand that it is not only from the burning of gasoline, but also from industrial coal burning. Sulfur dioxide is a chief contributor to acid rain, causing acidification of rivers, lakes, and streams. It also aggravates respiratory and cardiovascular problems .
Lastly, carbon dioxide has been increasing in the earth’s atmosphere since the industrial revolution. For all the naysayers out there, pay attention. Fossil fuels contain mainly carbon. When they are burned they react with oxygen and produce carbon dioxide. I know, common sense, keep reading. Light energy from the sun arriving at the earth has wavelengths shorter than 4,000 nm. Carbon dioxide in our atmosphere is not able to absorb these small wavelengths of energy. Therefore, energy from the sun passes through the atmosphere and reaches earth where it is absorbed and thus heats the planet. Here is where it gets interesting; heat energy from the earth has wavelengths greater than 4,000 nm, which CO2 can absorb. When heat leaves earth it is absorbed by the CO2 in the atmosphere. This sends CO2 into an unstable state, and to stabilize it releases the energy it just absorbed, but some of this energy is sent back to earth and some is sent out to space . This next figure from the Schlumberger (world’s largest oilfield services company) educational website shows this process. From the Schlumberger website they state, “There is a clear relationship between atmospheric CO2 concentrations and global temperature.”
Figure 1. CO2 molecules trapping heat energy and sending the heat out in all directions .
As seen above, CO2 is trapping heat from our own earth and sending it back down to us, hence the greenhouse effect. If you do not believe me, look up how carbon dioxide works yourself. This graph from the NOAA shows the trend of increasing CO2 in the atmosphere.
Figure 2. Chart shows increase of atmospheric carbon dioxide .
Not only is the atmosphere paying for this abundance of CO2, so are the oceans. The NOAA states in their May 2008 State of Science Fact Sheet that the oceans have absorbed 50% of the carbon dioxide released from burning fossil fuels, resulting in chemical reactions that lower the pH of the ocean. This has caused an increase of the Hydrogen Ions in the ocean leading to the acidification of our oceans. Ocean acidification slows down the rate at which corals, marine algae and free-swimming zooplankton produce and maintain their skeletons. Also, studies have indicated that this acidification has adverse impacts on the survival of larval marine species, including commercial fish and shellfish .
Burning coal to produce electricity is the single biggest man-made contributor to atmospheric carbon dioxide in the world . Just because electricity “looks” clean, do not be fooled.
 U.S. Energy Information Administration. Coal Explained. Energy Explained. [Online]. Available: http://www.eia.gov/energyexplained/index.cfm?page=coal_environment
 U.S. Environmental Protection Agency. Coal. Clean Energy. [Online]. Available: http://epa.gov/cleanenergy/energy-and-you/affect/coal.html
 A.H. Lockwood et al., “Coal’s Assault on Human Health,” Physicians for Social Responsibility.
 NASA Earth Observatory. Climate Forcings and Global Warming. [Online]. Available: http://earthobservatory.nasa.gov/Features/EnergyBalance/page7.php
 NOAA. Atmospheric CO2 at Mauna Loa Observatory. [Online]. Available: http://www.esrl.noaa.gov/gmd/webdata/ccgg/trends/co2_data_mlo.pdf
 NOAA. Ocean Acidification. State of the Science Fact Sheet. [Online]. Available: http://oceanservice.noaa.gov/education/yos/resource/01state_of_science.pdf
 Schlumberger Excellence in Education Development. CO2 and Temperature Change. Global Climate Change and Energy. [Online]. Available: http://www.planetseed.com/relatedarticle/co2-and-temperature-change