

Illustration by Heather Jones for TIME

How can a six-story, 50,000-sq.-ft. office building in downtown Seattle function completely off the grid? The answer involves solar panels for energy, geothermal wells for heat, a giant rain cistern for water and composting toilets for keeping sewage out of everything else. The toilets were just installed at the Bullitt Center, which is set to be completed this fall. “You have to remember to flush before and after,” says Bullitt Foundation president and Earth Day founder Denis Hayes. “But that may be the single largest lifestyle change.”

Hayes’s Seattle-based sustainability-advocacy group is bankrolling the largest multistory project that is trying to meet the superstringent requirements of the Living Building Challenge (LBC). Created in 2006 by the Portland, Ore.,-based International Living Futures Institute, LBC calls for buildings to not only have net-zero energy and water systems, but to use half the energy required to get LEED platinum certification (which is administered by a fellow nonprofit). LBC won’t certify a building as “living” until it has proven it meets the group’s goals for a full year after people move in. So far LBC has certified only three buildings worldwide, all of them in the U.S. and all exponentially smaller than the Bullitt Center. Another 140 projects in eight countries are vying for the designation.

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What makes the Bullitt Center so impressive is its height — or, more accurately, its relatively small rooftop — and its location. While it’s pretty easy in cloudy Seattle to harvest rainwater and treat it via an onsite biofiltration system, getting enough sunlight to power the building required rethinking every aspect of the project, big and small. The builders had to get a variance from the city to let its rooftop solar panels hang out over the sidewalk. But the solar panels won’t do all the work. The building’s design and its tenants have important roles too. To help cut energy consumption to 23 percent the amount of a traditional building its size, natural light will account for 82 percent of all lighting, thanks to oversized windows and higher ceilings that help get light farther inside. And so will air, as the building’s electronic “brain” automatically opens and shuts the windows based on temperature needs, eliminating the need for air-conditioning units.

Even with the building managing vital systems, users must make lifestyle changes, taking the stairs instead of the elevator, for instance, and choosing MacBook Air laptops — which pull less energy than a 100-watt bulb — over a desktop. As for those special toilets, their contents will get composted and decontaminated before being shipped off-site to be used as fertilizer.

The $30 million facility, at $265 per sq. ft., is expensive, but not outlandish. Mary Ann Lazarus, director of sustainability at HOK, one of the largest architecture firms in the world, is not involved with the Bullitt project, but says she hopes it will meet LBC standards and help prove that “what may have seemed like a wild and crazy idea can work at different scales.” Adds Hayes: “You’ll be surprised at how normal this is.”

Sources for the graphic: Bullitt Foundation; PAE Engineering; Miller Hull

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