Thursday, June 24, 2010

“Net-zero energy” home nearing completion in Urbana

“Net-zero energy” home nearing completion in Urbana

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Last September, on the Fall equinox, Debra and Ty Newell began construction of a new home in northeast Urbana. Barring any unforeseen hang-ups, they will move into it this July. In some ways, the house is like other 1-story homes in Beringer Commons, where it is located. It features about one-fourth an acre of usable yard, approximately 2,100 square feet of living space and a two-car attached garage. The Newell’s home differs from others nearby in that it will generate as much energy as it uses in a year, making it a net-zero energy house.

How is that possible? There’s nothing futuristic about it.

The Equinox house will achieve net-zero in part by using far less energy than even a well-built conventional home—about one-fifth as much.

The walls and roof of the Equinox House are constructed with twelve-inch thick structural insulated panels, which are four to five times more effective at preventing thermal transfer than the walls of a typical house. Great care has also been taken to minimize any leakage of air through envelope of the house

The Equinox House uses high performance, triple-pane windows, which also help to prevent thermal transfer. Beyond that, the windows are oriented to allow direct sunlight into living space for the heat it provides during the cooler half of the year—beginning on the Fall equinox—and to exclude direct sunlight during the warmer half of the year—beginning on the Spring equinox—when it would increase the load on the cooling system.

The demands of the Equinox House for heating, cooling, ventilation, and humidity control will all be met by a single, heat-pump based system, developed by Ty Newell and his son Ben through their company, Newell Instruments. Aside from the fact that it maintains a comfortable temperature and level of humidity in the house, this system also delivers a constant flow of fresh air from the outside, and it does that without the loss of conditioned air that occurs in a drafty house.

Of course the Equinox House will be fitted out in other ways that emphasize conservation, including LED lighting, low-flow plumbing fixtures, etc. It even features a system for collecting rainwater that is designed to meet 80 percent of the annual water needs for a family of four.

Although the Equinox House is designed from top to bottom to conserve energy, it will still require electricity to operate. So to be “net-zero energy,” it will produce some, by means of a ground-mounted array of solar panels. The solar array has been in service since February of this year and already produced enough electricity to offset all of the power used in construction of the house.

In addition to providing the energy required to run the Equinox House, the Newell’s solar array will also generate enough electricity to power an electric car (c’mon Chevy Volt, go Nissan Leaf!) for something like six to nine thousand miles worth of driving every year.

Does the idea of a net-zero energy home intrigue you? The Newells hope so. That’s partly why they chose to build where they did—so people could see their house in the context of a conventional development, and understand building it as a natural step for conservation-minded baby boomers preparing for retirement.

You can learn more about the Newell's home at the Equinox House Construction Blog at
http://newellinstruments.com/equinoxblog.html