BOULDER, Colo. -- It's "going green" on a gigantic scale.

The University of Colorado is renovating old dorms into state-of-the-art buildings. It said the project will pay for itself and then some.

CU claims Arnett Hall is the only renovated dorm in the country to receive LEED gold certification. LEED stands for Leadership in Energy and Environmental Design.

The residence hall is full of environmentally-friendly features like sensors installed on every window that automatically turn the heater off if students leave them open.

It also boasts recycled carpet, energy-efficient appliances, and low-flow bathroom fixtures.

"That's actually one of the reasons I came here," said Arnett Hall resident and CU freshman Haley Heinemann. She's an active member of the Sierra Club and said CU's commitment to the environment put the school at the top of her list.

The Arnett Hall renovation was completed in August 2008 and cost $12.5 million. The university is now renovating other buildings in the same 40-year-old housing complex.

Utility costs for campus housing are about $6 million per year. It said the upgrades will save a total of 25-30 percent on its bill.

CU said the renovations benefit both the school and the students.

"In one hand you're saving money, you're saving energy. On the other hand, you're providing an opportunity for students to learn because they live in this environment," said Moe Tabrizi, campus energy conservation officer.

The university is paying for the project with money it collects from the students' room and board fees.