Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New ORNL roof system means savings for homeowners

29.08.2007
Homeowners could see their summer utility bills fall by 8 percent or more with a new roof and attic system being developed at the Department of Energy's Oak Ridge National Laboratory.

From an energy efficiency perspective, roof technology has not progressed substantially in hundreds of years, but that is changing with the use of active thermal mass components, reflective pigments and coatings, subventing, radiant barriers and other novel techniques being tested by a team led by Bill Miller and Jan Kosny of ORNL's Building Envelopes group. Their prototype roof and attic system works by reducing attic temperatures by about 22 degrees Fahrenheit during a typical summer afternoon and decreasing the amount of heat that gets transferred through the attic floor to the living space.

At the heart of new roof system is a proprietary inorganic phase change material sandwiched between two reflective surfaces made of aluminum foil. This material is installed as a dynamic thermal barrier between the roof and attic area, creating separate air channels between roof rafters. The configuration is compatible with traditional wood and steel framing technologies. Moreover, the new phase change material overcomes problems that have plagued phase change materials for the past 40 years.

"In the 1970s and 1980s the housing industry made several moderately successful attempts to use phase change materials," Kosny said. "While these materials enhanced building energy performance, they were in many cases chemically unstable, were subject to corrosion or other durability problems and suffered from loss of phase change capability."

Another shortcoming of some previous phase change materials was their susceptibility to fire. Fire is not a problem with the ORNL material, according to Kosny, who noted that ORNL researchers are working with leading manufacturers of phase change material on the development of non-flammable organic material.

In tests at ORNL, phase change materials perform like conventional materials by absorbing heat as the temperature increases. However, as the material melts it continues to absorb large amounts of heat without a significant increase in temperature. Then, as night falls and the ambient temperature around the liquid phase change material decreases, it solidifies again and releases the stored heat to the night sky, Miller said.

With an outside temperature of 92 degrees Fahrenheit, tests at ORNL's Buildings Technology Center show temperatures of conventional attics at 127 degrees Fahrenheit vs. attic temperatures of 105 degrees with the Dynamic Attic Heat Exhaust System. Kosny and Miller filed a patent last year for this technology.

"The next generation roof will consist of infrared reflective materials that are dark in color yet reflect light as if they were white," Miller said. "In addition, radiant barriers and phase change materials will be integrated into a dynamic attic system that reduces utility bills for homeowners. The conservation strategies contribute on a much grander scale by lowering peak demand on utilities, reducing carbon emissions and, ultimately, they could lead to cleaner air."

If just half of the homeowners in the U.S. made sure they had R30 attic floor insulation and used this roof and attic system, the nation could reduce its Btu (British Thermal Unit) demand by about 100 trillion Btu.

This research is funded by the DOE Office of Energy Efficiency and Renewable Energy's Building Technologies program. UT-Battelle manages Oak Ridge National Laboratory for the Department of Energy.

Ron Walli | EurekAlert!
Further information:
http://www.ornl.gov

More articles from Architecture and Construction:

nachricht Smart homes will “LISTEN” to your voice
17.01.2017 | EML European Media Laboratory GmbH

nachricht Designing Architecture with Solar Building Envelopes
16.01.2017 | Fraunhofer-Institut für Solare Energiesysteme ISE

All articles from Architecture and Construction >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

Sandia uses confined nanoparticles to improve hydrogen storage materials performance

27.02.2017 | Interdisciplinary Research

Decoding the genome's cryptic language

27.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>