Optim Energy and NRG Energy Inc. (NYSE: NRG) jointly built a 550-megawatt (MW) combined cycle natural gas unit, Cedar Bayou unit 4, at the existing NRG Cedar Bayou Generating Station in Chambers County, Texas near Houston. This unit reached commercial operation in June 2009.

Optim Energy Marketing is the energy manager for all of the capacity of Cedar Bayou 4. The Marketing group exercises full control over unit dispatch decisions related to the plant.

Cedar Bayou 4 is one of the most efficient generating plants in the Houston area. This unit starts quickly to respond to rapidly changing load conditions.

Cedar Bayou 4 operates on clean-burning natural gas. The plant uses emissions control systems that the Texas Commission on Environmental Quality approved as Best Available Control Technology. The combustion turbines are fitted with ultra-low nitrogen oxide (NOx) burners which minimize the production of NOx. In addition to the low production of NOx, the plant uses Selective Catalytic Reduction technology to further reduce NOx emissions.