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Anthropogenic carbon dioxide (CO2) emissions and the resulting influence on global climate change have motivated nations throughout the world to reconsider how we obtain, move, and utilize energy. Use of the Sankey diagrams produced annually by Lawrence Livermore National Labs (see https://flowcharts.llnl.gov) indicates that in 2011, energy harvested in the United States was converted to electricity (40%), used for transportation (28%), or used for heating and industrial processes (32%). Similarly, in 2010, energy-related CO2 emissions were due to electric conversion (40%), transportation (33%), and heating and industrial processes (27%). (Including non-CO2 greenhouse-gas emissions does not significantly change these percentages.) Because energy-related CO2 emissions come from the combustion of fossil fuels (coal, petroleum, and natural gas), there has been much emphasis on reducing reliance on these fuels or shifting some use of coal or petroleum to the use of cleaner-burning natural gas, along with reducing energy consumption via efficiency improvements and conservation.