“Cool” took on a whole new meaning at University of California in 2015. The 10 campuses took the Cool Campus Challenge to see which campus could slash its carbon emissions by the most points.

More than 19,000 students, staff and faculty enrolled, making pledges online to do everything from carpooling to getting rid of mini-fridges to unplugging phone chargers and other “energy vampires” that suck up power even when they’re not in use.

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The challenge is part of the Carbon Neutrality Initiative from UC President Janet Napolitano, former chief of Homeland Security. She has pledged to reach zero emissions at California’s state university system by 2025 and has urged students, staff and faculty “to wipe out our carbon footprint for good.”

Kira Stoll, University of California at Berkeley's sustainability manager, helped develop the Cool Campus Challenge. “If each one of us takes a handful of new actions — turning off lights in our offices and common areas, or holding a virtual meeting instead of jumping in a car or phone to attend — we can knock these emissions down,” she said at the start of the competition.

Noting that UC Berkeley’s energy use contributes about 3 tons in greenhouse gases per campus person, Stoll added, “It’s conceivable that individual and team action can reduce emissions by five to 10 percent. This is the equivalent of taking 3,000 cars off the road or switching 11,000 California homes to solar electricity. And if everyone in the UC system does the same, the savings could be 10 times that, or more.”

As part of the challenge, UC Berkeley's Cal Dining invited students to join its “Green Bear” program, which includes efforts to compost food waste; others worked on campus gardens. Each action taken at all the campuses garnered a certain number of points based on Berkeley’s Renewable and Appropriate Energy Laboratory’s carbon footprint calculator, which shows how lifestyle habits can reduce (or contribute to) global warming.

On December 15 the University of California at Irvine was pronounced the winner of the challenge. Among its “cool” innovations:

  • A “Smart Labs Initiative.” Before it, an “enormous amount” of energy was expended in labs as the air was exchanged every four to eight minutes. Now the rate of air recycling depends on the number of people in the labs.
  • “Hydration stations” at which students can fill reusable water bottles to reduce plastic bottle waste. These stations have helped save more than 37 tons of plastic waste annually.
  • A sustainable transportation program designed to reduce the number of cars on campus by encouraging everyone to walk or bike to class and offering incentives to take public transportations, such as subsidized bus passes and train ticket rebates. The program also matches students with campus carpools and vanpools.
  • Recycling, “Meatless Mondays” and “Carbon Foodprint” labels (which tell students how sustainable their food choices are) in dining areas, as well as three zero-waste dining commons. UCI’s food sustainability program also sends food waste as fuel to the local water district to help power its plant. The program runs four campus community gardens and helps source organic, locally grown and sustainable foods (such as cage-free eggs) for student dining.
  • Solar energy expansion. UC Irvine is quadrupling the amount of green power it produces on-site by adding solar photovoltaic canopies on three campus parking structure roofs.

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Susan Suleman is a freelance writer who divides her time between the United States and Africa.