The National Institute of Standards and Technology (NIST) is putting the finishing touches on a net-zero-energy demonstration home that the federal agency hopes will identify green and energy-efficient strategies that transfer well to the real world.
“We saw the need for a test bed for new energy-efficient technologies, and we saw it as a way to demonstrate that it is possible to build a house that, over the course of a year, will generate as much energy as it uses,” says Hunter Fanney, chief of the Engineering Laboratory at NIST’s building environment division. “We also wanted to show that a house like that could be designed to fit into a typical suburban neighborhood and look like any other house on the block.”
Announced in March 2011, the Net-Zero Energy Residential Test Facility being built at NIST’s Gaithersburg, Md., campus is a 2,700-square-foot, two-story structure that will feature all the latest innocuous green and energy-efficient elements, such as energy-saving appliances and solar panels. But those elements are merely dregs compared to the real meat of the project.
“This structure is different from an average home because we have built into it multiple systems that can be operated and measured independently, allowing for ongoing, comparative research,” Fanney explains. “For example, whereas a real home might incorporate a single geothermal system, this facility has three—slinky loop, vertical loop, and horizontal loop—as well as three separate sets of ductwork to accommodate three different manners of supplying conditioned air to the facility.”
Even the photovoltaic system is different. It’s “reconfigurable and will allow us to select a power output between 2.6 [kilowatts] and 10.2 [kilowatts],” Fanney explains. “The solar thermal system features a variable-sized collector array and storage tank capacity.”
The NIST project may look like a house, but technically it’s a working laboratory—one that will undergo monitoring and testing in the coming years.
“We will be conducting a year-long test during which we will simulate a family of four living in it,” says Fanney. “The house is fully automated so that we can control details such as when appliances operate, when and where the lights turn on, and when showers run and for how long—even at what temperature.”
“No humans will live in the house, but it will be fully furnished and devices in each room will simulate the ‘family’ moving from room to room, using appliances, emitting body heat and water vapor,” Fanney continues. “We will have control over, and a record of, the energy performance of the entire house over that year, and how its various systems performed. You could not do that in a real home with people living inside.”
After a year of testing and monitoring, the agency will use the facility to develop and evaluate measurement science for low-energy and net-zero-energy buildings. “The data collected during the year-long net-zero test will be used to verify how close energy consumption predictions, made with EnergyPlus software developed by the Department of Energy, come to actual measured performance,” Fanney explains. “The data will also allow us to understand how well the various components work together, providing a clearer picture of their capabilities.”
Designed and built to receive LEED-Platinum, Energy Star 3.0, and Indoor airPLUS ratings, the house is expected to be fully constructed by the end of the month, at which time researchers will begin installing the computers that will run the automated equipment.
NIST, a physical sciences laboratory that is part of the U.S. Department of Commerce, received funding for the project through the American Recovery and Reinvestment Act of 2009.
For a time-lapse video of the construction, visit http://www.flickr.com/photos/usnistgov/.
