Michael Pratt, Brandon Brown
1School of Electrical and Computer Engineering
Georgia Institute of Technology
Atlanta, GA 30332
The average American citizen consumes energy over the course of a year which contributes to mankind’s total carbon emissions. Given current studies on the effects of Global Warming and carbon emissions, it is beneficial to analyze ways to reduce energy usage, and thus carbon emissions. The experimenters are assumed to be average American citizens aged 18 – 25 in terms of yearly carbon emissions. Their yearly energy usage was approximated, and local power plant emission data was used, when necessary, to calculate the total carbon emissions over a year. Practical methods to reduce these emissions were then evaluated.
1. Introduction: The Greenhouse Gas Effect
As more countries begin to go through their own industrial revolutions, American needs to worry more and more about being a paragon for emissions reduction. Globally the US accounted for 18% of total CO2 emissions . The three major carbon-based greenhouse gases are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). All are byproducts of the burning of fossil fuels (coal, natural gas, and oil). Figure 1. Global greenhouse emissions by gas. 
These gases trap heat in the earth’s atmosphere through a process called the Greenhouse Gas Effect. They can remain in the atmosphere from a few years to a few thousand years and subsequently raise the average temperature of the planet, as has happened on Venus over the course of its lifetime. Subsequently, the effects of greenhouse gases may not be experienced in full effect for many years after they are emitted. As seen in Figure 2, the US hasn’t reduced its emissions very much over the past 20 years, but has increased by 8.7% in total. Figure 2. US Greenhouse gas emissions since 1990 3
2. Sources of Energy
According to the EPA, energy production accounted for 85.5% of total carbon emissions in the US in 2011 . The burning of fossil fuels comprises most of these emissions with C02 being the primary byproduct. For the year 2011, Georgia Power supplied energy in relative amounts shown in Figure 3.
Figure 3. Generation sources of energy from Georgia Power in 2011. 
Coal, oil and gas, which comprise 79% of power generation, are the sources which produce carbon emissions. In the US the average level of emissions per MWh for each type of generation is shown in Table 1. The emissions for N2O are factored into the total under the assumption that they have a global warming potential (GWP) 298 times greater than that of CO2 . This gives them what is called a “carbon dioxide equivalent” in terms of lbs of CO2. | |CO2 |N2O |lbs/MWh (CO2 eq.) | |Coal |2249 |6 |4037 | |Gas |1135 |1.7 |1641.6 | |Oil |1672 |4 |2864 | | | |Total |8542.6 |
Table 1. US average carbon emissions per MWh.
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3. Energy Usage to Carbon Emissions
Using Table 1 and Figure 2, one can approximate total carbon emissions based on total energy usage from Georgia Power over a year. Assuming total energy consumption over the course of a year from Georgia Power is X MWh, then total carbon emissions footprint in terms of lbs of CO2 (averaging oil and gas) is approximately
Finding the value of X is complicated. According to the US Energy Information Administration, the average American household uses 11,280 kWh per year. Dividing this by four people yields...