Frequently Asked Questions

  • A simple answer is yes but not necessarily often. However, to maintain optimal function and efficiency - cleaning your solar panels on a regular basis is advised. It should be noted that the frequency you clean your solar panels is entirely dependent on your environment or time of year. Living in an area with less rain could mean you should clean your solar panels more often than someone who lives in an area with much rainfall.

    Maybe you are one of those who have researched solar and own a system for your home. You are now enjoying the benefits of it as your electricity bill gets slashed to pieces. You tell your friends what a great investment it is to go solar and how it not only affects the environment positively but it reduces your electricity bill significantly.

    But maybe you aren’t as aware of the maintenance required to optimize your solar system absorption. There are reasons why cleaning solar panels is extremely beneficial for someone who owns a system.

  • Yes, dirty solar panels are less efficient than clean ones. Dust, bird droppings, and leaves hinder the solar panels to operate at maximum efficiency. The efficiency rating of the panels is based on the optimal performance of these panels which are adversely affected by general uncleanness. Though SunPower systems have the highest efficiency rating on the market, even these panels can be affected negatively by the buildup of dust or dirt.

  • The important thing is to maintain the optimal output of your SunPower system. There can be a decrease of 1.5% to 6% of solar output annually due to collected dust or other particles.This is a very conservative figure as the same study showed that in dustier areas or places with higher pollution the numbers can range between 2% and 50% on conventional solar panels.

    The kinds of particles from the pollution that drastically hinder the photovoltaic process the most are:

    Ash
    Calcium
    Limestone
    Soil
    Sand
    Silica

    All pollution has some form of dust that negatively affects the maximum productivity of solar panels. Los Angeles along with Bakersfield are the cities with the worst pollution in the U.S. This means that dust from pollution affects southern Californians and central Californians the most.

  • Not only will dirt and airborne pollutants affect the production of solar panels, but they will also harm the solar cells themselves. A conventional and regular cell shaded by dust gatherings will act as a resistance to the power generated by other cells and this, in turn, causes the shaded cell to heat up and damage cell.

    Many solar systems are not independently connected to a microinverter and rely on the surrounding cells to maintain solar productivity. SunPower cells, however, are all independently connected to the microinverter and the cells around one another are not affected in any way by each other. If one cell were to be shaded or covered in dust, the others will continue working fine without damaging the shaded cell. But the production of that one cell will still be affected by the dust.

  • The National Renewal Energy Laboratory indicated that cleaning solar panels are much more needed in areas with infrequent rainfall, like Southern California. Rain tends to flush out a lot of the unwanted residue sitting patiently and waiting to devour the sunlight headed towards your panels.

    “In Southern California, we do not get frequent rain to clean solar panels naturally,” said DJ Schramm, co-founder of Green Convergence and 30-year plus roofer. “So bird droppings, airborne particles from dirt, pollen, and pollution fall out, mix with dew to create grime and slime that reduces the ability of the solar array to perform at full capacity. Dirty panels reduce the return on your investment. We have seen losses as high as 30%.”

    Rain, however, is not the cure-all for cleaning solar panels because rain still contains within it “airborne dust particles” that will still leave a layer of dust on the panels. This means that although rain may wash out the old dust on the panels, it brings with it new dirty particles.

  • Besides all the “dust talk”, let’s assume that you are interested in cleaning your panels by yourself. A lot of solar companies would not recommend that because of safety and liability reasons. To clean your solar panels you would need to ascend to the top of your roof and scrub the panels yourself which can pose a danger to some. Although this may save you some money, it is highly discouraged because of the delicate nature needed in attending those panels as well as the principle of "safety first."

  • No, you should not use a pressure washer to clean your solar panels. Power washers are good for many things, but cleaning solar panels is not one of them. Pressure washers are too powerful to clean solar panels safely and can end up causing scratches or other damage. If your solar panels are dirty, it's best to use a non-abrasive sponge and soapy water. Better yet, call a professional who can ensure that the job is completed properly and safely.

  • It is generally recommended to clean solar panels every 6 months to a year in order to maintain the productivity, efficiency, and effectiveness of the panels. However, based on where you live and the level of dirt and pollution, the need for cleaning may be more frequent.

  • Our prices range based on the complexity of your roof. For example, the proximity to powerlines or the distance to accessible roof planes could determine the different types of equipment needed. On average we see a $20/panel range.