New asphalt chemistry holds solar promise

Researchers at Worchester Polytechnic Institute (WPI) in Western Massachusetts say they've found a way to put pavement surfaces to use for solar energy collection.

The team experimented with various asphalt compositions and found the addition of highly conductive aggregates, like quartzite helps produce good results. The presence of the material increased heat absorption in contrast to the way a special reflective coating of paint can
reduce heat absorption, researchers said.

Roads and parking lots are typically resurfaced every 10-12 years. Retrofitting those lots and roads with equipment to collect solar energy would transform those large surfaces into solar farms, the WPI said.

Experiments were conducted on small slabs of asphalt in research labs in which temperature penetration was measured. The majority of the heat was found to be concentrated in the few centimeters below the surface, a potential optimal location for placing heat exchangers to collect and utilize solar energy.

The research project was sponsored by Novotech, Inc. in Acton, Mass, which holds the patent on the concept of using heat absorbed from pavements for energy uses.

Rajib Mallick, associate professor of civil and environmental engineering and PhD candidate Bao-Liang Chen are to present their research findings next week at the annual symposium of the International Society for Asphalt Pavements in Zurich, Switzerland.

Researchers also suggest heat exchangers with conduits of pipes could produce hot water for buildings or industrial processes. That same hot water could be sent through a thermoelectric generator to produce electricity, the researchers noted.

Cleantech developments making news in the past 24 hours

• Qteros claims 15-fold improvements in cellulosic ethanol yield
• Solairedirect raises €20M to move into commercial solar
• Intel, Numonyx open $20M water treatment plant in Israel
• Booming data-center business creates troubles for India

View the last week of cleantech developments here | Subscribe to full feed