Zero Energy Idea House
Zero Energy Idea House
Demonstrates Energy Independence
"Conserve first, generate energy second" was the mantra behind the design of the Zero Energy Idea House created by Shirey Contracting Inc. The 1,630-square-foot, two bedroom home in the Bass Cove area of Bellevue combines energy generation with conservation, resulting in total energy bills that are expected to be less than $40 per month.
Owners-developers Donna and Riley Shirey say they built the structure, which overlooks Lake Sammamish, to inspire other homeowners to adopt technologies that work toward energy independence.
The house incorporates several green construction features and displays energy statistics so homeowners get instant feedback on consumption and can adjust their input and output. On-site power generation is combined with efficiency measures so the home meets its own energy requirements. Rooftop panels power the home's electrical needs.
In late July, the home underwent pressurized blower door test conditions and subsequent thermal imager inspection on its building envelope. Tests showed it was more than three times as efficient as the standard for Energy Star homes.
The tests were performed by energy audit professionals from Fluke Corporation in cooperation with the Washington State University (WSU) Extension Energy Program.
The tests also revealed some unexpected results, but nothing that alarmed the project team, according to Mike Lubliner, Building Science Specialist with the WSU Extension Energy Program. "All of the unexpected areas of potential energy loss were found using thermal imagers and we believe with minor modifications, even greater energy savings will be recouped because of this technology," he explained.
"We are encouraged with the thermal imaging test results and think we may have built the most energy efficient home in the Pacific Northwest," said Donna Shirey. "Reducing airflow in a house is one of the best ways to conserve energy, and here we have built a home that exchanges air only twice every hour. Compare this to the average new construction home which exchanges air about 10 times an hour; an old home which has about 20 air exchanges per hour; even an Energy Star qualified home needs to be just under 7.0. At 2.0 we think we are looking really good," she exclaimed.
The project's technical tem opted to forego "true" zero energy by installing a gas-powered hydronic in-floor radiant heating system, described by Mike Lubliner of Washington State University Extension's Energy Program as the most efficient heating system available. Lubliner's office manages the Northwest ENERGY STAR® Homes program as well as the U.S. Department of Energy's Building America program, which has adopted the project as a case study.
The house at Bass Cove is built with structural insulated panels (SIPs), polystyrene panels that combine framing, insulation and exterior sheathing in one system that can be used for roofing, walls or floors over crawl spaces. SIPs are custom-manufactured from project drawings, and although they are a little more expensive than typical framing materials, they save considerable time, labor and waste on the jobsite and result in a structure that is tightly built and extremely well insulated.
Along with energy efficiency features, the "Idea House" incorporates sustainably produced and durable materials, healthy indoor environmental features, low impact site development, and natural landscaping.
The Zero Energy Idea House (www.zeroenergyideahouse.com) is the latest in "green" home projects around the state. Others include the Built Green™ Home at Suncadia (Roslyn), Going Green at the Beach (Stanwood), Elder Health Home (Tacoma) and Puget Sound Energy Build Green™ Idea Home.
Thanks to the NWREporter for this article.