Getting Maximum Performance from Flexible and Semi-rigid Walk-on PV Solar Panels

eSolar cell output degrades and the cell heats up.  A solar panel power rating is established at standard test condition (STC) of 77 degrees Fahrenheit and at 1,000 W/sq meter of light.  At 135 degrees Fahrenheit, a typical solar panel will degrade in performance by at least 10%.  It is not uncommon for a solar panel to reach 170 degrees in full sun on a warm day.  So, it is beneficial to solar panel performance to cool the panel as much as possible.  One way to accomplish this is to place 4 or 6 mm twinwall polycarbonate under the panel.  This enables some airflow under the panel thus cooling the panel.  Twinwall polycarbonate is often available at Home Depot or Lowe's or online.  Twinwall polycarbonate can also be used under a flexible pane on bimini canvas installation where the panel is going over a support tube.  This takes the pressure off the solar cells caused by bending at the support tube.  The panel and twinwall polycarbonate can be attached to the supporting surface using the CMP bolt on system or for semi-rigid panels the J extrusion system.

Bonus water heating idea:.  8 mm twinwall polycarbonate will accept 1/4" irrigation tubing.  The tubing can be run through the twinwall polycarbonate and attached to a small pump and the boat water heater.  Circulating water through the tubing under the panel will both cool the solar panel and heat the water in the hot water tank.  Free warm water!  See our water heating section on the website for further ideas on how to install such a system. 

6mm Twinwall Polycarbonate

Twinwall Polycarbonate Under a Semi-rigid Walk-on PV Solar Panel

8 mm Twinwall Polycarbonate with 1/4" tubing for water heating and panel cooling.