Solar Air Heat Solutions

Solar air heat systems that use air to move heat are an extremely cost effective way to supplement the heating load in your home or business.  Where the site is appropriate for a solar hot air system, we expect that when properly installed only insulation, weatherization and air sealing measures will be more cost effective for the homeowner or building owner.

Solar hot air collectors have the appearance of a large window box or sliding door, and mount vertically on the outside southern wall of a home or commercial building.  During the winter months, the sun’s rays come in at a low angle to the earth, hit the solar hot air collector and warm up the absorptive metal plate inside.  The air inside the collector is warmed and blown into the conditioned space through a short length of duct work.  The cool air from the room is drawn back in through a return.  The amount of electricity used to power the blower and a damper is a fraction of that which would be used to heat the space with electric resistance heating.

Some other considerations include:

-While solar hot air systems do not contribute to reducing the heating load at night, which can be less of an issue with a commercial building that is not used heavily at night;

-Although solar hot air collectors can be mounted on a relatively steep roof, this is not preferable; and

-Although the heat output from solar hot air collectors can be brought into the existing ducting/distribution system of a house or commercial building, this is not ideal.

Sound application of a solar hot air system requires a site assessment.  While there are rules of thumb regarding sizing of a system, all installations ought to account for the characteristics of the home or commercial building that is the installation is planned for.  These factors include not only solar exposure during winter months, but seasonal heating load, occupant comfort or discomfort, draftiness, and the extent of prior energy audit, insulation, weatherization and air sealing work.