NEW HAVEN, Conn. (AP) -- Yale is seeing green, but it's not the university's multibillion-dollar endowment.

Worried about global warming, Yale has embarked on an ambitious initiative to become the greenest university in the country. The goal is to cut its heat-trapping "greenhouse" gas emissions to 10 percent below the 1990 level by 2020.

"The consequences of global warming are going to be severe if it continues unabated," Yale President Richard Levin said Friday in an interview with The Associated Press. "It's only going to be solved by committed action across the planet."

Yale is among a growing number of universities and smaller colleges around the country cutting emissions in response to concerns about global warming.

At least 70 institutions have adopted commitments to deal with global warming, including Cornell University, Tufts University, Bowdoin College, Middlebury College, the University of California and the University of North Carolina at Chapel Hill, according to Julie Newman, director of Yale's Office of Sustainability, who runs a consortium of colleges and universities dealing with the issue.

Yale's 13 million square feet of buildings are kept a couple of degrees cooler in the winter and warmer in the summer than they were in the past.

The school is buying hybrid cars and using biodiesel fuel for buses. Motion detectors shut off power when no one is around and students in university housing compete to conserve energy.

Yale is also increasing the efficiency of its power plant and using "green architecture" for new buildings. That involves techniques such as installing windows that reflect heat in the summer and absorb it in the winter and placing them to minimize energy use.