Jeff Christian: Zero Sum Gain
He is energy efficiency guru and architect of Oak Ridge National Laboratory's unique living lab of energy-efficient and renewable generating technologies. The pursuit of zero-energy housing has no greater champion than Jeff Christian.
In 2002, when the Department of Energy introduced the daunting concept of a house that would produce as much energy as it used, Christian seized the challenge and has not let go. Guided by the belief that energy-efficient homes should be affordable to working families, he partnered with the Habitat for Humanity in neighboring Lenoir City, building five homes to test the latest in renewable energy producing and energy-efficient technologies. The homes feature such as solar panels, geothermal heat pumps, heat pump water heaters, airtight superinsulated walls and roofing panels and advanced ventilation systems. They demonstrate that such technologies, when properly integrated, work in real-life environments with regular people who can then benefit from the resulting cost savings. That accomplished, he is now helping transition the concept—and the technologies—to the traditional construction industry, with plans under way to begin building locally two "near-zero-energy" homes aimed at traditional home buyers. Christian said he hopes one of the homes will be part of the 25th anniversary of the 1982 World's Fair held in Knoxville.
With the zeal of an evangelist, Christian has brought together a diverse group that includes the nonprofit Habitat organization, utilities, suppliers, contractors, architects and researchers to demonstrate today what Christian believes is becoming a model for America's homes of tomorrow.—Larisa Brass
Q. Talk about how the zero-energy home concept began.
The idea was introduced to me for the first time in March 2002. I was among three representatives from Oak Ridge National Laboratory to go to Washington, D.C., where we heard the message that the Department of Energy was going to fold all of our buildings research under the umbrella of the zero-energy house. I not only said I thought this was a good idea but I came back and approached the Tennessee Valley Authority and Habitat for Humanity with the idea of being the first on the block to get something that was very near zero-energy and affordable. At first I thought of building something like a carport to get on the ground quickly. It was the Habitat coordinators themselves who said, "The people we serve don't need carports—they need groceries and they need a decent house. Why don't we just make it part of one of the houses we build?" By June, we had a house. I went on my annual pilgrimage to TVA in Chattanooga and proposed that they fund five near-zero-energy test houses. They very quickly pointed out that TVA is in business to sell energy and that "zero" did not sound like a good proposition on the surface. Then they realized the potential benefit of peak load reduction, which could be a strong motive for electric utility interest in the project. Before you know it, TVA committed to funding, with the Department of Energy, five zero-energy houses. Then-chairman Glenn McCullough said he hoped the houses would "propagate across the residential, commercial and industrial sectors." We are now in the last year of testing the fifth house.
Q. What are the most influential technologies for energy efficiency and energy savings in a home?
The Habitat houses are, in essence, airtight and mechanically ventilated. That is a clear starting point. This is followed by installing the heating and air conditioning ducts inside the conditioned space. From there we go to high-performance windows and—as a result of creating a well insulated, airtight home—downsizing the heating and cooling distribution system and the mechanical equipment. That means a dollar savings generally, although what we have found is we have pushed the capacity so low that there are no systems small enough to help owners achieve the full cost savings potential. That has spawned a focused effort within the ORNL Buildings Technology Center to develop integrated, high efficiency, affordable, smaller-than-commercially available technologies.
Q. What makes a Habitat for Humanity community ideal for this research?
First of all, these homes are very sustainable. You build something, you test and when you are done testing the home is turned over to a family in need, who gets an upgraded, affordable home out of the deal. The houses are small, they are simple, and they can be fairly easily replicated. The community, in essence, gives us a laboratory facility. We have a half-dozen field exposure facilities spread around the country, as well as world-class laboratory facilities, but there are some pieces of information in which we simply need a whole house to conduct our research. This community provides an unprecedented capacity for building research.
Q. What is the impact of actually having people living in the houses?
It is both a blessing and a curse. You have real people and the interface issues are very important. But you also must have things that are ready for prime time. You do not, for example, want to be responsible for cold showers— something I have been accused of. A real benefit is that many people think a near-zero-energy house needs to be occupied by an engineer, tweaking things at every moment to make the house go. To that I simply say, not true. Our research offers a strong testimony that these homes can be easily occupied by average, non-technically oriented residents.
Q. What must happen to achieve the goal of a true zero-energy home?
The first thing that we will reach is zero-energy cost. Currently, the Tennessee Valley Authority buys all the solar power you generate for 15 cents per kilowatt hour. I am very hopeful that will be increased to at least 20 cents, maybe 25 cents, and I'm asking for 30. The Department of Energy has set a target date of 2020 for development of affordable zero-energy homes. To do that, however, we need a couple of things. We need the cost of solar panels to come down. Researchers looking at solar feel like we can reach affordable cost within that timetable. The second issue is that we need to deal with an increasingly out-of-control miscellaneous electric load. This is not lighting, appliances, heating and cooling or hot water. This is everything else—cell phone chargers, electric toothbrushes, hairdryers, plasma televisions, VCRs, Tivo boxes and your home office with computers, faxes, printers. This extra demand amounts to 2,500 kilowatt hours per year per household and is growing at an outrageous 3.5% per year. With today's technologies and capabilities at ORNL in development of advanced sensors and controls, we can combat this growing problem.
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