For the purpose of section 103 of the Powerplant and Industrial Fuel Use Act of 1978, a powerplant's design capacity shall be determined as follows:

(a) Steam-electric generating unit. The design capacity of a steam-electric generating unit shall be maximum generator nameplate rating measured in kilowatts or, if the nameplate does not have a rating measured in kilowatts, the product of the generator's kilovolt-amperes nameplate rating and power factor nameplate rating.

(b) Combustion turbine. The design capacity of a combustion turbine shall be its nameplate rating measured in kilowatts, adjusted for peaking service at an ambient temperature of 59 degrees Fahrenheit (15 degrees Celsius) and at the unit's site elevation.

(c) Combined cycle unit. The design capacity of a combined cycle shall be the sum of its combustion turbine nameplate rating measured in kilowatts, based on baseload operation adjusted for site elevation, and the maximum generator nameplate rating measured in kilowatts of the steam turbine portion of the unit.

(d) Internal combustion engine. The design capacity of an internal combustion engine shall be the generator's nameplate rating measured in kilowatts.

(e) Sunsetting provisions. This section shall cease to have effect on December 5, 2026, unless the Commission determines that the cessation deadline should be extended to a date not more than 5 years in the future after offering the public an opportunity to provide input on the costs and benefits of this section and considering that input. The Commission will publish a document in the Federal Register announcing its determination and revising or removing this section accordingly.