Cogeneration is proving to be the most cost-effective use of sludge gas at many wastewater treatment plants. The cogeneration system Brown and Caldwell designed for a wastewater treatment plant at Oxnard, California, completed in 1981, recently won an award for energy innovation from the U.S. Department of Energy. In recognizing the Oxnard system, DOE stressed the technology’s ability to be transferred and used by other organizations in similar circumstances. Charles R. Imbrecht, chairman of the California Energy Commission, stated at the award ceremony that the Oxnard system has already been emulated at 12 other cities in California and is expected to be used throughout the country.