A new generation of high performance buildings are demonstrating they can attain net zero energy use over the course of a year.
But there is great debate over how they do it. Can they buy renewable energy credits to achieve net zero? Must they generate 100 percent of their power from renewables onsite? What about combustion, and is that truly net zero?
"There was a lot of confusion in the marketplace about what net zero really means," Amanda Sturgeon, vice president of the International Living Future Institute (ILFI), said last week during a panel discussion on net zero certification during the Institute's annual Living Future conference.
The Institute is known for administering the Living Building Challenge, formed in 2006 with the aim of being a more stringent approach to green building certification than USGBC's LEED certification. To be certified as a Living Building, a building must not only be net zero energy, but also net zero water and waste.
In response to the varying definitions of net zero energy, ILFI also created a Net Zero Energy Building Certification for net zero buildings in 2011. The first building to achieve Net Zero Certification was IDeAs Z2, the San Jose headquarters of engineering firm Integral Group.
Net Zero criteria
Net Zero and LBC certification require performance monitoring for a full year after occupancy. This verifies the building is truly operating as claimed, and is a value added for the client, according to the panel of architects and engineers pursuing imminent certification on these net zero projects. They include the David & Lucile Packard Foundation (pictured above), zHome residential development, Jackson Sustainable Winery, UC Davis and DPR Construction's Phoenix Regional Office.
All Living Buildings are automatically certified as Net Zero buildings, but not all buildings going for Net Zero Certification need to pursue Living Building status.
However, Net Zero certified projects must meet some of the non-energy requirements of the Living Building Challenge, including site, beauty and equity.
"We require net zero buildings not be built on ecologically sensitive sites," Sturgeon said.
They must also follow the rights to nature imperative so, for example, the buildings are not allowed to block someone else's solar access.
Image courtesy of EHDD.
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