Archive for the ‘Solar Thermal’ Category

Carlisle-Energy Saving Skin for Roofs

Wednesday, October 8th, 2008

Cities are hot: Filled with skyscrapers, traffic and hot pavement, heat simmers between buildings causing the “heat island effect”. Stagnant heat is trapped in the narrow city gaps and air conditioners cooling the inside of buildings spill even more heat out the walls. Trees offering natural cooling and shade are minimal and soil that helps water evaporation (thereby cooling the area) is non existent. Replacing the trees and soil are dark streets that store heat and reach temperatures up to 70F (21C) hotter than lighter surfaces. Stifling heat is depressing (unless you’re at the beach), and the added smog and clouds that form because of it, don’t help matters either.

The Environmental Protection Agency (EPA) states that “for millions of Americans living in and around cities, heat islands are of growing concern. This phenomenon describes urban and suburban temperatures that are 2 to 10°F (1 to 6°C) hotter than nearby rural areas. Elevated temperatures can impact communities by increasing peak energy demand, air conditioning costs, air pollution levels, and heat-related illness and mortality.”

Sure White Fully Adhered EDPM
(Photo: Carlisle SynTec)

Carlisle Syntec Incorported, one of the biggest single-ply membrane roofing companies, provides a product that helps cut down on the ‘heat island’ issue. If, however, energy costs need to be cut back because of heat escaping in winter climates, they have solutions for that too.

Carlisle has developed membranes for over 40 years and their popularity has increased substantially in that time: Demand exploded as early as the 1970s, during the Arab Oil Embargo when Asphalt became scarce. In the 1980’s Carlisle stretchable roofing technology accounted for 40% of the non-residential roofing market. Now, as continued in their company timeline, “Carlisle reaches out domestically from 21 manufacturing locations, 80 manufacturer and representative offices and eight regional sales offices to serve the non-residential single-ply roofing marketplace.”

Their roofing materials are developed for a variety of needs. Their thermoplastic polyolefin (TPO), is a white reflective material that, after easily being rolled over and attached to rooftops, cuts down on buildings’ cooling costs and energy usage. Logically, the reflecting material also helps cut back on the heat island effect. Cool roof products are becoming increasingly popular: in the past three years, for example, Carlisle has rolled out more than 400,000 square feet of TPO.

Carlisle specializes in a variety of roofing needs: For cooler climates, where it isn’t necessarily beneficial to reflect heat, darker heat absorbing membranes are used on rooftops. The company also designs unique skylights and a variety of roof gardens.

With the ease of application, the environmental benefit and the aesthetic appeal of these roofing systems, it won’t be a surprise if bland dark roofs are soon a thing of the past.

 

Streets for Solar

Tuesday, August 19th, 2008

Steam rises from the never-ending stretch of road ahead. What looks like water rolling over the street, is just heat escaping. Walking on the blacktop barefoot would leave anyone but a fire-walker grunting in pain.

Our planet is covered with a web of streets and this cement absorbs and stores an abundance of the sun’s energy. Researchers at the Worcester Polytechnic Institute (WPI), are looking into ways of using this heat as yet another renewable energy source. They have already developed solar collectors that would transfer the energy into electricity.

The ball started rolling with the president of Novotech Inc., Michael Hulen, who funded the research project meant to prove the efficiency of Novotech’s patented heat absorbing design. Based in Acton, Massachusetts, Novotech is one of the biggest suppliers of infrared optical and semiconductor materials.

WPI’s research was presented at the Annual Symposium of the International Society for Asphalt Pavements August 18-20, in Zurich, but like most things in life, the presentations are not accessible for free so I have no information about WPI’s results as of yet. (In addition to the topic of ‘roads for energy production’, other areas of interest such as noise reduction, recycling, drainage and environmentally friendly maintinence on pavements were also discussed at the event.)

The idea of using already existing streets as solar panels is a promising one; Roads are reworked every few years and the technology can be incorporated when repaving is necessary. Not only that, but the unfortunate truth is that roads, parking lots and sidewalks are more common than anything else in many areas. With Novotech’s design, at least these concrete landmasses can be retrofitted as solar power generators.

The heat collectors would be located a few centimeters underneath the pavement, not changing the outward appearance. Cars will roll along on the roads, as usual, but now power will be generated right underneath the tires.

For more information, check out an in depth article at Science Daily.