Cornell is ranked No. 21 out of 162 colleges and universities nationwide by Sierra magazine, a bimonthly magazine published by the Sierra Club.

The magazine singled out Cornell's new Combined Heating and Power Plant, which was designed to reduce the university's carbon dioxide emissions by about 75,000 tons per year and eliminate coal consumption completely by 2011.

The plant, which uses natural gas and steam power, is part of a campuswide effort to reduce the university's net greenhouse gas emissions to zero by 2050.

The magazine's rankings were based on submitted surveys covering 10 categories: energy supply, efficiency, food, academics, purchasing, transportation, waste management, administration, financial investments and other initiatives. Universities were scored from zero to 10 in each category based on their survey answers.

Cornell scored 10 in investments and other Initiatives; and 9 in academics, purchasing and administration.

The university didn't participate in the survey last year, but the ranking is up from years past, said sustainability coordinator Dan Roth. "It's gratifying to get recognition for all that Cornell is doing in so many sustainability areas," Roth added.

The survey was constructed by the Sierra Club's editorial team, according to the magazine, with guidance from the Sierra Club's Conservation Department and outside campus sustainability experts.