As Yale struggles to catch up to its more environmentally-conscious peer institutions, some campus activists are pushing for initiatives they say may help make the University more green.

Hundreds of student advocates for Yale environmental reform joined the Climate Campaign to petition for superior fuel efficiency and reliance on renewable energy sources during last Friday’s “Fossil Fools Day” drive. Yale students involved in the Climate Campaign — a coalition of 12 student environmental networks with 308 participating universities — are pressuring administrators to import at least 10 percent of the school’s energy from renewable sources like solar or wind power.

The 10 percent mark is necessary in order for Yale to join the greener ranks of its Ivy League counterparts such as Harvard or regional peers such as Connecticut College, Climate Campaign members said. But some Yale officials said the process will not be as quick as activists would like.

While Yale’s School of Forestry and Environmental Studies gets approximately 20 percent of its energy from renewable sources, Sustainability Coordinator Julie Newman said the rest of the campus is not in a position to take that approach.

“There’s no way that any one of these sources can run our whole system,” Newman said. “Hopefully we can find a way to aggregate energy to get ourselves there. Professionally, I want to make sure that whatever promises we make, we can achieve them.”

Some members of the Climate Campaign said although the 10 percent mark would be difficult to reach by their target date of next year, New Haven and state officials have committed to the more aggressive “20 percent by 2010” campaign, and Yale should be expected to rise to the challenge.

“It’s a pretty bold demand, but we’re pretty sure Yale can do it,” Caroline Howe ’07, the campaign’s state coordinator, said. “What President [Richard] Levin said in his most recent open forum was that he would commit to that.”

Levin said Monday that he supports such initiatives, but objected to the most efficient current methods of purchasing renewable energy — buying renewable energy “credits” to subsidize producers.

“They’re simply substitutes,” Levin said. “Unless you actually are going to create new hydropower or wind power, you’re just transferring money to the producers of the renewable power and not actually reducing pollution or carbon dioxide.”

Still, Howe said the renewable-energy subsidy program is the simplest way to make the University as a whole more environmentally friendly. While Newman’s position is less than a year old, Harvard has been investing in renewable energy credits for nearly five years, culminating in a recent $100,000 commitment to additional credits.

“I think Harvard’s recent actions should push Yale in a really positive way,” Howe said. “Harvard is doing a really great job and is really putting us to shame. I hope the administration is really taking that to heart.”

Howe and environment school spokesman Dave DeFusco said the environment school is a major advantage in Yale’s campaign. Among some Green Fund-sponsored projects are a “bio-fuel project” designed to recycle waste cooking oil into fuel to heat Yale’s Bethany Observing Station; a new “electric recycling vehicle” billed at $10,600; and $12,000 worth of new recycling bins strategically placed around campus.

“We’re starting to see a rapid greening of the blue,” DeFusco said.

Senior Energy Engineer Tom Downing said an open forum on energy reform will be held Thursday to discuss basic existing plans and future possibilities.