No. 1: John W. Turk Jr. Power Plant, operated by Southwestern Electric Power Co. in Arkansas. Operating capacity of 609-MW. Heat rate: 8,858 btu/kWh
The John W. Turk Jr. Power Plant is the first plant in the U.S. to use the ultra-supercritical steam cycle that helps cut emissions of SO2, NOX, mercury, CO2, and particulate; reduces the production of solid waste products and reduces requirements for water and commodities such as activated carbon, lime and ammonia. Advanced alloys are used in the steam generator, turbine and piping to operate in conditions about 1,100°F (593°C).