[Home]   [Full version]  

Energy-efficient house a wish come true for Santa

Dec 20 ,General Science


Christmas costs can make us all a bit less jolly, but there are a number of ways even Ole St. Nick can save money throughout the year and help offset the high cost of the holiday.
For openers, the Clauses could live in a Department of Energy near-zero-energy house. If the savings are typical of those in Tennessee, this would cut their hypothetical monthly North Pole electric bill from about $400 to $200, said Jeff Christian, director of the Buildings Technology Center at Oak Ridge National Laboratory. ORNL has an important role in DOE's Building America Near-Zero-Energy House program.

While energy-efficient houses save the homeowner money throughout the year, the biggest savings come during the heating months, Christian said. At the North Pole, where the mean monthly temperature is 32 in July and minus-22 degrees in December, the heat bills – and the savings -- never end. Closer to home, the savings vary according to the climate, but in Knoxville, where the average low temperature in December is 32, a homeowner can save $100 or more per month with a near-zero-energy home.

Following are average December low temperatures as provided by Weatherbase for select cities around the country dating back some 40 years: Anchorage, 10; Atlanta, 36; Boston, 27; Chicago, 20; Cincinnati, 27; Denver, 18; Detroit, 22; Kansas City, 26; Knoxville, 32; Memphis, 35; Minneapolis, 11; New York, 31; Nashville, 31; Salt Lake City, 22; Seattle, 38; Tahoe City, Calif., 21; Washington, D.C., 32.

While true near-zero-energy houses are designed from the ground up, owners of existing homes can realize a number of benefits by doing some simple things around the house.

"For example, a fireplace is an enormous source of lost heat if it is not sealed correctly," Christian said. "A lot of people have glass across the front of the fireplace opening, but the damper is left open when no fire is burning, and that can cause a huge air leak into and out of the house. Of course, you'll want to leave the damper open on Christmas eve."

An open damper in a fireplace is the equivalent of having a 30-by-6-inch hole in the roof, or about 180 square inches. And a conventional house has additional air leakage that can be the equivalent of a hole that's even bigger. Meanwhile, a near-zero-energy house has air leakage that equals an area of about 13.5 square inches, Christian said.

Where total energy savings are concerned, the largest gains are possible during the heating months. While buildings consume 36 percent of our country's total energy resources, 33 percent of that is used for heating while 10 percent is used for cooling, 15 percent for heating water and 42 percent for everything else. In a near-zero-energy house, the percentage used for heating drops from 33 percent to 14 percent.

Near-zero-energy houses feature airtight envelope construction, advanced structural insulated panel systems, insulated precast concrete walls, a heat pump water heater, geothermal systems, grid-connected solar photovoltaics, adaptive mechanical ventilation, cool roof and wall coatings with infrared reflective pigments, and solar integrated raised metal seam roofs.

In the future, Christian said geothermal systems have significant energy-saving potential. These systems take advantage of heat that has been stored in the earth all summer. ORNL and a major heating, ventilation and cooling system manufacturer recently signed a cooperative research and development agreement aimed at bringing lower cost geothermal systems to market.

"While today's near-zero energy houses on average are using 50 percent less energy than the national average, our goal is zero energy," Christian said. "And a true zero-energy home would make the Clauses and everyone's Christmas a little better."

ORNL, which is managed by UT-Battelle, employs 1,500 scientists and engineers and is the Department of Energy's largest multipurpose science and energy laboratory.

Source: DOE/Oak Ridge National Laboratory

Related stories:

Scientists view both Obama, McCain as supportive
(AP) -- Call it the political revenge of the nerds. For nearly eight years, many mainstream scientists have been frustrated with the Bush administration. They've claimed that science has been censored, ignored and politicized on issues from global warming to stem cells to evolution. Even the presidential science adviser was booted from the White House, forced to set up office down the street.
Transforming the 1930s house into an energy efficient home of the future
The 1930s semi is an icon of its age. Three million were built and they are still a major part of our current housing stock. Now a three year research project is about to start at The University of Nottingham that will help people living in these properties meet the Government's ambitions to reduce CO2 emissions from homes.
Economic woes chill effort to stop global warming
(AP) -- Attempts to tackle global warming are being made more difficult by the spreading economic crisis even as Democratic congressional leaders say it's still a top goal for next year.
You too can be on the Forbes 400 list. OK, no you can't
Every year I look, and every year my name's not on the list. Yeah, the Forbes 400 Richest People in America. I'm not one and you're not one, either. Unless, of course, someone is reading this to you.
Making metabolism more inefficient can reduce obesity
In a discovery that counters prevailing thought, a study in mice has found that inactivating a pair of key genes involved in "fat-burning" can actually increase energy expenditure and help lower diet-induced obesity. These unusual findings, appearing this week in the JBC, might lead to some new roads in weight-loss therapy.
Writing patterns, logos and lettering in light
(PhysOrg.com) -- Logos and lettering can be written in light using freeform lenses. But how does the surface of the lens have to be structured in order to focus the light in the shape of a specific pattern? This used to be a task that took hours – now it can be done in a few seconds.
Scientists warn US Congress of cancer risk for cell phone use
The potential link between mobile telephones and brain cancer could be similar to the link between lung cancer and smoking -- something tobacco companies took 50 years to recognize, US scientists warned Thursday.
What energy upgrades would you make for $250?
It's a double whammy: Home energy costs are rising just when most of us can least afford it.

News discussion:

General Science news

[Home]   [Full version]