Natural gas from Devonian shales is usually composed primarily of methane (80-95%), with a small mix of ethane and propane (3-15%) which require processing before commercial sale. When natural gas and other fossil fuels are burned to
produce energy, the amount of energy produced is measured in BTUs (British thermal units) per standard
cubic foot (scf), with higher BTUs indicating greater energy production. One BTU is the amount of energy
it takes to heat 1 pound of water by 1˚ F. Because of the composition of the natural gas varies, the potential
energy production from Devonian natural gas ranges from 900-1300 BTUs per scf.