All About Solar > How Solar Cooling Works

Solar absorption cooling – or solar air conditioning using an absorption chiller – is one of the most efficient and cost effective solutions for commercial air conditioning and space heating. The world's first air conditioners used thermal energy to provide cooling, and this technology is common in the northern east coast USA and is used for refrigeration in campers, RVs and the like.

This type of cooling is powered by solar evacuated tube collectors, which collects solar thermal heat from the sun. This energy is then collected and transmitted into a solar absorption chiller by means of a heat transfer fluid (HTF). This HTF is generally comprised of water and corn or propylene glycol, it is designed for the most efficient heat transfer as well as providing freeze protection in the winter. The HTF then passes into the solar absorption chiller and thus powering it, providing free, solar air conditioning.

Absorption chiller air conditioners are not new, they have been commercially used in the U.S. since the early 20th century and are a very widely deployed technology. Absorption chiller AC units are also very popular in Asian countries like Japan, where the high cost of electricity make them very desirable and they constitute up to 40% of all installed commercial air conditioning tonnage. They are simple and dependable, using no harmful CFC (Freon, etc.) and some units actually operate without any moving parts.

When engineered to run on solar energy the absorption chiller AC units provide the lowest cost to operate and the best return on investment of any air conditioning system in the world.

Our solar heating and air conditioning units can be used anywhere that the sun shines; they are low in operating and maintenance costs. They consume little or no electrical energy – essentially the only parts that use electricity are low amp fan motors and small pumps that move the thermal transfer fluid (Glycol, a food-grade antifreeze) from the collectors to the chiller and then back up to the collectors - all of these small electrical loads can run from solar PV panels if desired. Inside the unit is another small pump that circulates the refrigerant. There is no "compressor" to consume power.