Solar thermal collectors: Tips for beginners
Dr. Jay Sampat of Southeast Solar Co. breaks down solar thermal collectors for laymen.
Fri, Jun 17 2011 at 3:49 PM
Photo: Southeast Solar Co.
Dr. Jay Sampat is a distributor of solar thermal collectors and the owner of Southeast Solar Co. His company has successfully installed solar thermal collectors in several homes and businesses in and around Atlanta, and is expanding his market nationwide. Dr. Sampat is a physician turned green enthusiast who designed and built his own home after moving to Atlanta from Arizona. He proudly claims to have the most energy efficient home in Atlanta.
Dr. Sampat explained how solar thermal collectors are more viable to home and business owner not only in terms of the costs of materials, but also installation and maintenance costs.
Solar Thermal Collectors
Solar thermal energy is based on a simple concept where thermal energy absorbed from the sun is converted to usable heat. The thermal energy is absorbed by water, or a freeze resistant water mix in an evacuated tube which is then converted to heat through a fluid-to-air heat exchanger that can be installed in the existing plenum of your home. This heat can then be used to supplement hot water heating for daily activities, radiant floor heating and space heating through baseboards. The basic functions of a solar thermal collectors are:
Solar heat absorption
Solar heat transfer
Solar energy storage.
Key Components of Solar Thermal Collectors
To understand in depth how the system functions, learning about the key components of the solar thermal collectors is a good place to start. Here is the breakup of all the parts:
Copper heat pipes
Copper header pipe
Glass wool insulation
Mounting frame – there are several different methods of mounting.
Solar collectors that consist of hollow evacuated glass solar tubes made from extremely strong borosilicate glass, which collects energy from the sun. Also In the tube is a copper heat pipe that contains purified water or a freeze-resistant water mix. As the tube absorbs heat from the sun, the air inside this evacuated glass tubes is pumped out, creating a vacuum trapping the heat inside.
It's a Vacuum in There
Remember the thermos flask your parents used when you were a kid? Well, the heat is trapped pretty much the same way liquids stayed hot in the thermos. A vacuum is considered a very good heat insulator, and thus helps trap the heat inside the evacuated tube. The inside of the solar tube is lined with barium to maintain the vacuum state of the tube. The heat from this tube is then transferred via the heat pipe to the copper header, where a fluid (glycol) in the header helps transfer the heat to a air heat exchanger and finally stores the energy in a storage tank.
Each of these tubes are arrayed on a frame whose angle is designed to meet the Insolation levels in your geographical area. The entire system is then mounted on the your roof of your home. Sounds too complicated to DIY? Dr. Sampat and Southeast Solar Co. would be happy to help you.