Generally speaking, the answer is yes. Even you cleaning them yourself is a viable option. And it’s probably the most cost-effective. However, there are risks involved, that’s why most people are nervous about going up on their roofs and may not have enough of the equipment (like a long hose and spray nozzle).

Getting the pressure right can also be a little tricky. You don’t want to spray it too hard and violate the seal on the unit. But you need enough pressure to remove the dirt. Often times the best option is to hire a professional to clean your solar panels for you. This will guarantee the job is done right and protects your investment.

Pricing varies widely across Chicagoland. And a lot of it depends on the size of your solar panel installation, how easy it is to access it and where they can get water and power to their equipment. However, those are relatively cheap services and good value for money.

Your solar system represents a significant investment of capital. Allowing your solar modules to get soiled due to airborne particles, bird droppings, leaves, etc. can greatly reduce your electricity output. Additionally, by not cleaning your solar system at all, you may not only risk losing a significant amount of electricity output, but you may risk losing your modules too. Indeed, certain airborne particles may be quite abrasive and scratch the surface of the solar modules, causing permanent damage when they are not removed. Other organic deposits (e.g. windborne dirt, bird and other animal droppings, urban pollution (e.g. soot from burning coal or diesel), as well as decomposing organic plant matter from leaves, pollen, etc., can become wet and cause potential corrosion.

Hot spots are parts of your solar modules where heat is produced instead of electrical power. These hot spots not only decrease the energy efficiency of your solar modules but can also reduce their lifetime significantly. It is clear that the economic benefit of increased production and preserving the lifetime of the panels greatly outweighs the cost of periodic maintenance of the PV modules’ surface.

The frequency by which solar modules should be cleaned is of course dependent on the location and environment in which they are placed. However, the presence of heavy industry nearby, coastal areas, and heavy bird populations may warrant more frequent cleaning to assure optimal output and maintenance of your solar modules.

For solar modules placed in more dry and desert-like environments (subject to more dust) it is recommended to have the solar panels cleaned on a more periodic basis (e.g. on a monthly basis).

Over short periods of time dust, debris and droppings from birds will accumulate on your solar panels and reduce their efficiency. Many experts claim that this reduction can easily be as much as 25%. Only regular cleaning will keep them working at their highest output possible.

Rainfall alone does not suffice to properly clean and maintain your solar modules. Rain can remove some dust and dirt off the solar modules as a result of their smooth surface and tilted position. However, rain cannot deal with all dust and dirt and it is not an effective means to remove the contamination from bird droppings, chemicals, acid rain, and other air pollution. Additionally, rain may itself leave mineral deposits on the solar modules after evaporation.

Consequently, it is highly recommended to use proper and specifically designed cleaning products, which provide an all-in-one solution for all kinds of contamination.

In most of the cases no, it does not. In many cases, it is just the opposite. Regular cleaning of your solar panels will protect your investment and protect your warranty because it is recommended by the manufacturer.

However, if you lease your panels you should make sure whether you can clean them or not!

Although PV systems and their output have been well studied and statistically measured over the last 25 years, the effects of module soiling on performance have only recently been the subject of scientific analysis. It is a scientific fact that any object or element preventing photovoltaic cells from being exposed fully to the sunlight will decrease their output. International scientific research shows that the yield of solar panels is reduced by 3% to up to 15% on an annual basis as a consequence of soiling!

A study of the Netherlands Organization for Applied Scientific Research (TNO) has shown a decrease in energy production of 4,4% to up to 7,7% in 1 year caused solely by pollution. A 12-year lasting scientific research study by Mr. H. Haberlin proved a similar result. According to the Solar Electric Power Association (SEPA), photovoltaic electricity output will decline approximately 10% due to the accumulation of dirt, dust, and other residues.

Further research by the US-based Solar Electric Power Association (SEPA) indicates that PV electricity generation will decline 15-20% in areas where bird droppings, urban pollution, or dust from farming operations are common. Individual dealers have even reported losses as high as 25% from some customers who neglected to ever clean their solar modules.

Soiling of solar module surfaces is a complex phenomenon varying by climate, environment, and location. A surface in a dry desert-like location will be subject to electrostatically attracted inorganic materials, a surface in a coastal area will be subject to salts and rain-driven dirt, and a surface in an industrial and cooler location will be subject to organic windblown dirt, deposits from evaporated rain and atmospheric pollutants from fossil fuels. Generally, the soiling of an exposed outdoor surface (such as a solar module) will be a mix of organic and inorganic solids. Some of these solids will be windborne whilst others will be deposited from evaporated liquid (rainwater, dew, fog).

In wet and cooler places like Chicago, most of the soiling is organic and windborne, like organic droppings, algae, and plant matter (mainly from trees). All that can cause corrosion. In other words, it reduces the life and performance of a panel.