Now that Spring is upon us, we need to start thinking about making changes that will save energy during cooling season.  One of the things that can make a difference is shading your outdoor HVAC unit.  At our first house, the unit was located on the south side of the house and received full sun all day long.  The heat from the summer sun beat down on the unit relentlessly. 

The heat generated the sun’s rays beating down during a long summer day makes your unit run less efficient than it would if it were operating at a cooler temperature.  The solution?

Provide some shade to your unit.  I’ve seen this done primarily with fencing, but you could a plant a trellis with fast growing climbing plants.

It is crucial that you don’t block the air flow to the condensing unit of your system.  Be sure that whatever method of shade you use allows air to flow through it.  A fence should have gaps between the fence slats.  Build your fence at least 24 inches from the unit.

Can this really make a difference?  Research is mixed on whether shading your unit makes enough of a difference.  However, even studies critical of shading air conditioning units suggest that savings of up to 5% are possible.  A 5% reduction in your air conditioning bill during the hottest part of the summer certainly warrants a small investment in materials and a few hours on a Saturday morning.

Photo credit:  cabrantes