You sure do. Things like dust, bird droppings or leaves can block sunlight and reduce your system’s efficiency. For most homes, giving your panels a clean once or twice a year does the trick, but if you live somewhere dusty, near the coast or in a high-pollution area, a little more frequent cleaning might be needed.

Here are a few handy cleaning tips:

• Use a soft brush with an extendable pole and a garden hose.
• If your panels are tricky to reach, it’s safest to call a professional.
• Try to clean them on cooler, overcast days to avoid thermal shock and cracking which could be caused by hot panels and cold water.