An offshoot of Indiana University’s student government is urging students to take short, cold showers to save the planet.

“Living sustainably is one of the easiest things you can do,” the head of the student association’s newly founded sustainability department told the student newspaper. “Turn off your lights, unplug your electric devices, take shorter, cold showers. Maybe some people are deterred by that, but as time progresses these issues are going to become much more pressing and much more internationally important.”

Believe it or not, Indiana University isn’t alone; across the U.S., some students are adopting this goosebump-inducing environmental measure.

At Dickson College’s Center for Sustainable Living—a 14-person campus residence nicknamed the Treehouse—students are allotted just three minutes of warm shower water a day. One sophomore living there recently gushed that she “couldn’t be more excited for cold showers.”

At the Treehouse, heating is also rationed, with the indoor temperature kept no higher than 58 degrees during the winter. And their television, turned on only for “big events like the Super Bowl, Grammys and election debates,” runs on a bike-powered generator.

The University of California Los Angeles published an entire green-living guide, telling students to “always opt for a shower over a bath.” It also encouraged them to buy a waterproof shower timer and install it in their bathroom. That way, students can “measure the length of your shower, and then challenge yourself to shorten your shower!”

At Massachusetts Institute of Technology, dorms compete to save energy. To reduce individual usage, the college urges students to “take shorter and/or colder showers,” and also to “wear layers rather than turning up the heat” on cold winter days.

At other colleges, students have imposed Spartan shower rules on themselves, without institutional pressure.

Last year at Ohio State University, one student decided to replace one normal shower a week with a cold shower. “It’s disappointing because if I were to have been doing this my whole life, just taking one cold shower a week, I could have saved so much water and energy, and my life hasn’t been any better or more enjoyable because I haven’t,” he wrote.

At UC Irvine, a recent graduate said she was inspired to forgo hot showers—and her “entitled millennial” lifestyle in general—after traveling to Costa Rica for the university’s global sustainability program. In addition to taking only cold showers, she also started composting.

— Jillian Kay Melchior writes for Heat Street and is a fellow for the Steamboat Institute and the Independent Women’s Forum.