Green tech yields many benefits of passive design

Passive houses may not be well suited to the Mid-South, although green technology is making it easier to achieve the same goal.

Jack Cowan, owner of an energy audit and healthy home performance business called Cowanhouse (cowanhouse.com), has built two zeroenergy homes in Atwood, Tenn., that generate rather than consume energy.

They are not passive houses, which adhere to a rigorous set of standards that emerged from development in Europe and which, Cowan says, aren’t well suited to the Mid-South.

“The climate here is different,” Cowan says. “The passive house movement in Europe had different models, energy costs are much higher and the weather is wintry.”

Building a passive house to those standards in the Mid-South would, Cowan says, entail huge costs and the climate here is more of a mixed bag.

“The passive house works better in cooler environments,” he says.

But the zero-energy houses that Cowan has built utilize enough green technology so that energy is sent back to the grid, enough that the homeowners get a rebate. These homes score high on the HERS (Home Energy Rating System) Index, a method of scoring the energy efficiency of a house.

Jimmie Tucker, a founding principal at Self+Tucker Architects, says that the increasing use of LEED (Leadership in Energy and Environmental Design) ratings is changing the marketplace. LEED ratings gauge the design, construction and operation of high performance green buildings.

“Material costs are coming down,” Tucker says. “We’re seeing more companies that have the expertise to utilize the techniques.”

Tucker notes that the TERRA house in the Uptown area “has pushed the envelope — it was the first LEED -certified home in the area.”

The structure was a cooperative venture with the University of Memphis’ architecture department and private firms to include the latest green technology.

It is one of eight homes in the state to earn LEED Platinum status, the organization’s highest standard for green design.