When you think about the sun, heat is usually the first impression one gets. A recent twist on the idea has led to the possibility of cooling your home with the sun. Seriously!

Environmental concerns are a very important factor in a number of areas and air conditioning is one of them. The wide spread use of air conditioning has created ever increasing electrical energy demands, and the power generating capacity is struggling to keep up with this demand. During demand peaks created by hot spells, there have been power outages and brown-outs in the past. One of the ideas that has been developed to cope with this problem is the use of the sun as a power source. This seems a logical concept since the sun creates the problem by creating heat. How great it would be if the sun could also provide the solution.

In Europe, the technology for using solar energy for both heating and cooling is quite advanced and many larger building have been using a form of it for years. The method used is based on the thermo-chemical process known as sorption. Sorption takes two forms. When a liquid or gas is attached to a porous, solid material it is called adsorption. When the liquid or gas is taken in by liquid or a solid, it is called absorption. The European technology involves the use of a sorbant, usually silica gel. The silica gel is heated by the sun and is dehumidified. When water vapor or steam is added to the dehumidified gel, adsorption takes place and heat is released.

Basically, when heated ambient air is drawn through the system in what is called a heat reclamation rotor, the heat is drawn out of the air, cooling it. The cooled air is recycled back into the building. The major drawback to this system is the large size of the units, and of the area that must be exposed to the sun. This makes its use practical in large buildings, but not applicable for home use.

Solar energy for home use is an emerging technology also. However, the idea here is to use the energy to power existing air conditioning units rather than replacing them with new technology. Photovoltaic cells mounted on the roof converts solar energy into AC power that can be used to power the air conditioner. In most cases, the amount of power is not sufficient to run the unit, but can supplement the regular electrical supply. The major advantage here is that when the electrical demand is the highest, which would be during the peak daylight hours, the sun will be bearing down most directly on the PV cells.

There is a surge in power consumption during start up of an air conditioner unit. Solar photovoltaic cells can be used to keep the unit running at a very low speed during times it would normally be shut down. This can further reduce the regular electrical use by eliminating many of the starts and stops of the cycle. Solar energy is an emerging technology in a world that is seeking alternative sources of power. Hopefully, in the future, the sun, which creates the heat and humidity that we seek to eliminate with air conditioning, will provide the solution to our continued comfort.

Quinton Williams is with AirConditioningRepairCompanies.com - a directory of air conditioning repair companies as the name suggests.