(1) There is hereby levied and there shall be collected from every district operating a thermal electric generating facility, as defined in RCW
54.28.010 as now or hereafter amended, having a design capacity of two hundred fifty thousand kilowatts or more, located on a federal reservation, which is placed in operation after September 21, 1977, a tax for the act or privilege of engaging within the state in the business of generating electricity for use or sale, equal to one and one-half percent of wholesale value of energy produced for use or sale, except energy used in the operation of component parts of the power plant and associated transmission facilities under control of the person operating the power plant.