Monday, July 25, 2011:

Shade the Outside Central A/C Coil

Using the TED home power monitoring system, I noticed that between the hours of 5-8 pm, the duty cycle of the air conditioner goes way up. I also noticed that it was during those same hours that the setting sun is beating down on the air conditioner unit outside.

I decided to build a shade to see if that would improve anything.  

To my surprise, with the tarp shade, the power consumption of the air conditioner while it was running did not change much but the duty cycle of the air conditioner's "on" cycle, shortened.

That worked so well that I spent $100 on a couple sheets of grey PVC lattis and channel pieces.  I built a more permanent trellis shade that looks nice and still shortens the A/C duty cycle during the evening sun hours.

This shade results in a 1.9 kWh/day air conditioner energy savings with the added benefit of looking less like a crime scene than the tarp.