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*Update* - the below post was originally published in November of 2010.  The below graph shows how U.S. electricity production has shifted in 7 years.  In early 2015 Natural Gas took over from Coal as the leader in US electricity generation!  Also, in Jan of 2014 solar PV production finally grew to a point where it made sense to include it on the graph!  Data on U.S. Electricity produciton can be found on the U.S. Energy Information Administration Electricity Data Brower.

Original Post

Where does your electricity come from? Are you connected and totally dependent on the electrical grid or have you built a net-zero energy home? Does your region rely heavily on coal power like the southeast U.S. or are you blessed with hydro power like the northwest U.S.? We use electricity every day; to make our coffee and toast, microwave our food, iron our clothes, wash our clothes and dishes, light our home and business, cool our home, etc. And yet most people just think that electricity comes from a socket in their home. Before electricity reaches your home, it first has to be generated by something (we have yet to figure out how to capture electricity from lightning!). In the United States, we currently use the following sources to generate electricity (found from the Energy Information Administration link on Net Generation by Energy Source and Other Renewables and ranked from largest generation source to lowest generation source):

• Coal - Fossil Fuel
• Natural Gas - Fossil Fuel
• Nuclear
• Hyrdo - Renewable
• Wind - Renewable
• Petroleum - Fossil Fuel
• Wood and Wood-derived Fuels - Renewable
• Other Biomass (Biogenic municipal solid waste, landfill gas, sludge waste, agricultural byproducts) - Renewable
• Geothermal - Renewable
• Solar Thermal and Photovoltaic - Renewable

I created the table and graph below from the EIA data to show the U.S. electrical generation mix through the first 8 months of 2010.  As you can see, fossil fuels (coal and natural gas) currently make up almost 70% of our electrical generation!

U.S. Net Generation by Source - Jan. 2010 - Aug. 2010

The data above is for the entire U.S., but what sources make up the electricity generation in your state? Luckily the Department of Energy has a nice table showing from what sources each state in the U.S. gets its electricity from. The DOE also lets you see your state energy profile (not just electricity) that is very helpful and educational. What if you could come up with an electricity generation mix that raised the importance of renewable generation sources while lowered the percentage of electricity generated from fossil fuels? Luckily you can (at least in a game) by making your own energy cocktail, a project developed by the people at News 21 at UNC. If you follow the energy cocktail link and click "Play the Game" you can adjust sliders to get a mix of energy from different sources. Keep in mind this is total energy (including things like heat and transportation), not just electricity, but it still gives you a good idea. You can adjust sliders to vary the ratio of which source makes up the energy demand. I lowered the percentage of energy that comes from the dirtiest sources, coal and petroleum, and increased the percentage from nuclear and natural gas. While I would have loved to rely totally on renewable sources like wind and solar, I know technical and economic challenges make it a current reality that nuclear and natural gas will continue to remain a large part of our energy needs. I'm not the only one coming up with an improved energy generation mix. Deutsche Bank Climate Change Advisors has released a report titled "Natural Gas and Renewables: A Secure Low Carbon Future Energy Plan for the United States". Some key points highlighted in the report:

• This plan would involve a reduction in coal’s share of energy generation from 47% currently to 22% by 2030
• The share of natural gas generation increases from 23% in 2009 to 35%
• When combined with further renewables and nuclear deployment this would make the Obama Administration’s targets of a 17% over all economy-wide reduction in greenhouse gas emissions by 2020 and an 83% reduction by 2050, realistically achievable.
• We forecast wind and solar energy increasing to 14% of the US energy mix by 2030 compared to 2% today.
• Total electricity sector coal demand decreases from 930 million tons per year in 2009 to 460 tons per year in 2030.

Electricity is generated from many different sources in the U.S.  It is important for us to find clean sources that don't pollute the environment while also providing affordable electricity.  This is the first post in a series.  In later posts we'll dig a little deeper into each source and take a closer look into the positive and negatives of each generation source.