Harnessing the sun to cool the air
The very source of energy that creates the hot desert climate is now being used to keep desert dwellers cool, using a new technology unveiled last week by SRP and the Department of Emergency and Military Affairs (DEMA).
A demonstration solar absorption cooling system was installed to cool the Ecobuilding, a 5,200 sq. ft. structure at the Arizona National Guard's Papago Park Military Reservation.
"We know how important air conditioning is to our way of life here in the desert and we need to solve the technological challenge so that we can make solar-powered air conditioning a reality. Our work with DEMA is a step in that direction," said SRP Associate General Manager Richard Hayslip.
The solar thermal cooling system uses hot water produced by solar evacuated tubes. The cooling is provided by an absorption process that uses hot water, chemistry and a vaccum to make cold water. Cold water is piped to an air handler where cold air is blown into the Ecobuilding.
The building is a high-mass structure constructed primarily of used tires and earth that saves energy with active and passive day-lighting systems and generates energy with an 11-kilowatt solar photovoltaic (PV) array. The air conditioning system, which is powered by solar thermal collectors and an absorption chiller, is part of a research study into the feasibility of the technology. Solar cooling provides an advantage over traditional heating, ventilating and air conditioning (HVAC) by matching the highest cooling demand with the strongest summer sunshine.
SRP, in partnership with DEMA, contracted with Berquam Energy Systems of Sacramento, California for the design and installation of the system. DEMA owns and operates the solar system, while maintenance is provided by SRP. SRP has contracted with a third party to investigate the actual energy savings for this system over the next year.
