ScienceDaily: Americans used less energy overall in 2015 than the previous year, according to the most recent energy flow charts released by Lawrence Livermore National Laboratory. Each year, the Laboratory releases energy flow charts that illustrate the nation's consumption and use of energy. Overall, Americans used 0.8 quadrillion BTU, or quads, less in 2015 than in 2014. (A BTU or British Thermal Unit is a unit of measurement for energy; 3,400 BTU is equivalent to about 1 kilowatt-hour). Natural gas use increased...