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The DOE’s Change a Light, Change the World campaign misses the bigger point.

October 4th, 2007 · No Comments

The U.S. Department of Energy (DOE) is quite correct in suggesting that if every household in the U.S. substituted a 100-watt standard light bulb for a Compact Fluorescent Light bulb (CFL), it would eliminate an amount of carbon dioxide (CO2) equivalent to one million automobiles. However, it is the bigger picture that matters, – motor vehicles contribute the most to CO2 emissions. We must not forget that by focusing on CO2 emissions, they are admitting that CO2 is a real issue that potentially leads to global warming and climate change.

Let’s look at some facts about our carbon footprint. A 100-watt light in operation for 13.3 hours produces approximately one pound of CO2 when the electricity is generated by coal. Coal has significantly higher carbon emissions per kilowatt-hour (KWH) than oil or gas. Please see Carbon content of fossil fuels . Coal generates about half the electric power in the U.S. and produces roughly ¾ of a pound of CO2 for every KWH of electric. That means for every 1.3 KWH of electricity used (a 100-watt light used for 13.3 hours) we produce 1 pound of CO2. And remember it’s the oxygen in the air that contributes nearly 73% to the weight of CO2. This is why more CO2 is created than the actual weight of the fuel.

Using the same fuel emissions data, a motor vehicle with an average fuel efficiency of 22 miles per gallon (MPG), produces approximately 90 pounds of CO2 for every 100 miles driven. A gallon of gasoline produces nearly 20 pounds of CO2. That equates to one pound of CO2 for every mile driven by an SUV with a fuel efficiency of 19 MPG. (19.9 pounds/gallon times 1 mile divided by 19 MPG)

While it makes sense to address the issue of CO2 emissions, particularly as coal accounts for half of electric power generation and has higher CO2 emissions per KWH than oil, the real issue is an energy plan that givers us energy independence. Energy independence should equate to national security.

Tags: Alternative Energy · Automobile Fuel Efficiency · Carbon and Climate · Carbon Economics · Carbon Emissions · Carbon Footprint · CO2 Emissions · Coal Energy · Energy Economics · Energy Independence · Energy Security · Fuel Efficiency · Global Warming · Oil Energy · Transportation Energy Economics