^{*}*One measure of the efficiency of agas turbine that converts a fuel into heat and into electricity is the heat rate. To express the efficiency of agas turbine as a percentage, divide the equivalent Btu content of a kWh of electricity (which is 3,412 Btu) by the heat rate. For example, if the heat rate is 10,140 Btu, the efficiency is 34%. If the heat rate is 7,500 Btu, the efficiency is 45%*.