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The power output delivered from a photovoltaic module highly depends on the amount of
irradiance which reaches the solar cells. Many factors determine the ideal output or
optimum yield in a photovoltaic module. However, the environment is one of the
contributing parameters which directly affect the photovoltaic performance.
The soiling accumulated on the front transparent substrate of a PV panel may reduce the
power output and may even cause a hot-spot effect. The industrial effluents or bird
drops may be severe factors for affecting output, and the extent of the severity depends
on the transparency of the foreign objects. In general, when PV modules work, ideally no
environmental influencing factors should affect their operation, as these may distinctly
reduce the power output. Overall, there should be no obstructed object over the modules
surface at any time.
Soiling is basically the constant build-up of atmospheric dust, pollen, pollution, minerals and salts from rain water and other substances such as bird or insect droppings on your solar panels. Soiling reduces the energy output of the PV array, and can lead to various types of localized failures if the soiling is uneven.
Shading due to soiling is divided in two categories, soft shading such as air pollution, and hard shading which occurs when a solid such as accumulated dust blocks the sunlight. Studies show that soft shading affects the current provided by the PV module, but the voltage remains the same as the light intensity is still homogeneous on the dusty front surface of the PV module. In hard shading, the performance of the PV module depends on whether some cells are shaded, or all cells of the PV module are shaded. If some cells are shaded, then as long as the unshaded cells receive solar irradiance, there will be some output although there will be a decrease in the voltage output of the PV module.
This myth has been around for years, but the truth is slightly different. This is a myth! When a panel is called self-cleaning, it tends to mean that the surface is hydrophobic meaning water droplets cannot stick to the surface. In essence though, these surfaces are not exactly self-cleaning and maintenance free. They do reduce mineral residue that can block the sun reaching the cells, however, in a dusty environment a single solar cell within the panel can become inefficient and this will affect the performance of the rest of the cells within the panel. As they are wired in series, if one cell is shaded, then the output of the entire cell string is lower as a result. Additionally, rain alone is not enough to ensure solar panels remain free from a build-up of dirt throughout one year, let alone a lifetime.
Solar PV panels have been designed for easy maintenance. However, cleaning solar panels can assist in optimizing electricity output. The need for cleaning will vary dependent on the accumulating velocity of the fouling, location, rainfall, pollution levels and the angle of installation – the lower the angle of installation, the more cleaning will be required. To optimize electrical output, it is recommended to clean the panels when soiling can clearly be seen on their front surface. Depending on the place and environment, the front surface needs to be cleaned with different frequency periods. This is a matter of how much soiling would harm the expected solar yield.
‘Normal’ rainfall will naturally clean the panels if installed at a sufficient angle to ensure water runs off the surface. Nonetheless, even though rainfalls are free of charge, still there are seasonally volatile. Therefore, the reliability of this cleaning method is questionable especially when soiling is intense, and rainfall is not enough either in quantity or in intensity to wash off the soil. It is observed that sharp declines in performance have been noticed in various cases after a light rainfall. Wind can also assist to reduce or eliminate soiling to a certain extent, but there is a need of water to clean the surface for optimum power generation.
A good way to illustrate why rainwater will not clean solar panels is by looking at your car windscreen. If you didn’t clean your windscreen for 6 months, how much visibility would you lose? Even if the car is rained on, the rain contains airborne dust particles that settle and attach to the surface after the rainwater evaporates. When we use our windscreen wipers, we clean the center of the screen, but where the wipers do not reach, there is a film of dirt. The whole of your solar panel is in exactly the same condition as the edge of your car windscreen because they are both exposed to the same elements. Visibility through your windscreen is lost due to the loss of light. Therefore, the same principles hold true for solar panel cleaning. It is very important to maximize the light getting into the solar panel and in turn, increase your financial reward.
Yes. Just like dust gathers on your shelves and window sills, atmospheric dust, pollen,
pollution, minerals and salts from rain water and other substances such as bird or
insect droppings are constantly building up on your solar panels causing decrease of
their power productivity. Cleaning your panels does not just save you money, it gives
your panels a longer productive life span.
Eventually, the benefit of cleaning dirt and debris from the PV modules is a trade-off
between the cost of cleaning, the increased energy production as a result of this
cleaning, and the inevitable re-soiling of the PV modules over a period of time once
they have been cleaned.
Never attempt to clean solar panels yourself. There is always a risk of damage and
inefficient cleaning, but most importantly, a risk of electric shock.
Solar panel cleaning & inspection costs vary according to the installation size and
accessibility. WORKBEE can provide you with a solar panel cleaning & inspection price
estimate based on the installation size, but it is very useful for us to provide more
information of the PV array which will enable us to give an accurate solar panel
cleaning & inspection pricing.
Many owners of solar installations deal with the dirt on their solar panels in a fairly
haphazard way: with water, a mop and a brush. But a solar panel is not a window or the
kitchen table! Make no mistake: The panels are covered by glass, but it usually is a
specialised kind of glass often coated in an invisible and extremely thin
anti-reflective layer.
By simply wiping or brushing dust away, you risk voiding the manufacturer’s product
warranties. The manufacturers usually give quite specific instructions on how to clean
their solar panels. Sometimes these instructions can be very meticulous, as if calling
for you to clean your panels with a toothbrush.
For that reason, it is best to simply leave the cleaning to an expert. A professional,
specialist solar panel cleaning company like WORKBEE
will ensure that your panels are cleaned – while keeping the warranties valid.
The harshness of untreated water will leave marks behind containing mineral deposits,
especially in hard water areas. Untreated water marks can actually attract dirt as well
as being an inefficient cleaning process. Using only purified water to clean your solar
panels means that the minerals have been removed from the water using two processes.
Firstly reverse osmosis, this is then followed by de-ionisation, leaving behind a
purified water.
Manufacturers do not recommend the use of harmful chemicals or detergents to clean solar
panels. However, they do advise regular cleaning using purified water, especially before
the onset of summer and winter. Manufacturers also state that regular cleaning will
preserve their limited warranty and help to maintain the optimum output performance of
the solar panels.
Solar Panel Manufacturers recommend against using chemicals or detergents to clean your solar panels as these leave behind a sticky microfilm that attracts more dust and grime decreasing their efficiency. Abrasives also damage the glass and can even void the warranty of your solar panels. Tap water and rain will not keep solar panels running at maximum efficiency.
Every solar array is unique and depending upon different environmental factors, the
recommended frequency of each clean will vary. Special attention should be given to
panels situated in dustier areas, for example; next to a main road, by the sea and on or
near industrial zones and farmlands. These solar panels will require more frequent
cleaning as the dust build up will be considerably more.
When solar panels remain dirty for long periods of time, they suffer from modular
shading, in addition to this, permanent module staining may also occur and the larger
the array, the bigger the loss of return on investment.
In case of feed in tariff rates in place, this should also be taken into consideration
when choosing the frequency of solar panel cleans.
Our experience is that areas with low atmospheric dust, pollen, pollution, minerals and
salts from rain water and other substances such as bird or insect droppings require an
annual or even a bi-annual clean, with agricultural, city and coastal PV systems being
the dirtiest, therefore requiring a more frequent cleaning schedule.
Many clients contact us before their clean is due because they are experiencing a drop
in output due to their systems environment, especially following long periods of dry
weather, Sahara desert dust storms and light rainfalls.
Manufacturers state that dirty solar panels will result in a loss of output and may also
affect your warranty.
WORKBEE strongly advices on reading the entire
Installation and Operation & Maintenance manuals from PV panels manufacturers carefully.
The manuals contain critical information on safety, as well as detailed instructions for
the installation, operation, and maintenance of the PV panels. Failure to follow these
instructions and procedures will invalidate the product warranties.
Production increase varies according to the age of the installation, the location and
the angle that the solar panels are positioned. When anyone has solar panels installed,
they want to know how long it will take for them to get their return on investment
(ROI). Your solar panel installer may have told you or provided you with an attractive
estimation for your expected ROI. This figure was based on your solar panels always
running at their maximum possible efficiency during the course of a year. If your solar
panels continue to lose 30-35% of their output from not being cleaned, it will take you
some years extra to meet your expected ROI.
By having your solar panels cleaned by a professional company for a reasonable cost, you
will keep your solar panels running to their maximum efficiency and you will meet your
ROI expectations much sooner.
Solar panel cleaning & inspection costs vary according to the installation size and accessibility. WORKBEE can provide you with a solar panel cleaning & inspection price estimate based on the installation size, but it is very useful for us to provide more information of the PV array during your registration on our website which will enable us to give an accurate solar panel cleaning & inspection pricing.
The provided costing is based on the frequency of cleaning & inspection. For these reasons, each quote that we provide for solar panel cleaning is tailored specifically for you. Our prices do not outweigh the financial rewards that solar panel cleaning & inspection services will bring to your PV system. Please check our Solar Trust Plans for more information.
Solar panel cleaning & inspection services is what we do best. Because we haven't
diversified, we remain focused on perfecting the service we deliver to you. We are
experienced in cleaning & inspecting complex roof mounted solar panels to large-scale
solar farms, and everything in-between.
By working closely with our clients, we constantly strive to offer a robust value
proposition, to meet target deadlines, to problem solve and optimize our internal
processes, and earn ourselves an outstanding reputation within the solar industry.
With our strict “No subcontracting” policy, we ensure the solar panel cleaning &
inspection is completed by ourselves. This allows us to maintain consistent and
integrated solutions that sit under a robust value proposition and tailored to ensure
efficiency, effectiveness and cost optimization.
In addition to our broad experience and expertise, what makes us stand out is our total
commitment to our clients. As consultants, we can provide you with sector-specific
advice and support for all aspects of solar panel cleaning & inspection services.
We recognize that every project and client is unique. Our expert, targeted and
practical assistance can help support your organization for the cleaning & inspection
process.
Please contact us to openly discuss your requirements and to find the best offered
solution for your PV project today.