Skip to main content
Observer Ethical awards Winners 2011

YouGen Blog

How do you clean solar panels?

Posted by Jason Ramsdale on 29 February 2016 at 10:05 am

Whether or not you need to clean your solar panels sparks something of a debate between owners of solar panels. Most roof-mounted systems are self-cleaning as rain-water washes away the majority of the dirt that gathers on the surface. If you’re considering using commercial cleaning services calculate whether the cost of energy saved outweighs the cost of cleaning.

While most equipment loves to be maintained, most solar PV (Photovoltaic) systems have no moving parts, have a lifespan of decades and require very little maintenance.The most maintenance you really need to do is to keep your panels free from obstructions and shade and give them a routine inspection for damage if it is safe to do so.

How often should I clean my solar panels?

This is largely down to your area, if your panels are subject to more dust, leaf litter, grime or bird droppings more frequent inspection and cleaning will be required to maintain maximum output. Under normal conditions solar panels tend to need cleaning one or two times per year. While there’s no such thing as too clean it is worth considering that the more contact you have with the panels, the more likely it is that you will damage them.

What should I use to clean my solar panels?

  • In most cases the panels can be simply rinsed down with a garden hose.
  • For more persistent dirt a soft brush, sponge, cloth or squeegee can be used to wipe the panels. Wiping in small circular strokes should be enough to loosen most dirt allowing them to rinsed clean.
  • Absolutely NO abrasives! Most panels have a coating which is susceptible to scratching and removing this coating will likely mean more dirt and grime will build up in the future.
  • Depending on the coating cleaning products may damage your panels, if in doubt check the supplier’s guidelines or use plain water.
  • Be sure to rinse off any cleaning products to prevent any build up, and ideally dry your panels with a soft cloth to prevent any salt or calcium build up from the water.

Safety considerations:

  • It is best to keep your feet firmly on the ground or use a telescopic brush rather than climbing up to your roof where a small misstep could damage your equipment or result in a fall that could injure or kill you.
  • Check the supplier’s maintenance advice to determine which cleaning products are safe.
  • Check for exposed wiring as it could pose a risk to both your system and yourself.
  • Do not clean your solar panels whilst they are in or have been in direct sunlight, as they can be very hot and cold water could potentially cause them to crack.

Do I need to turn off my solar panels to clean them?

Broadly speaking solar panels cannot be “turned off” during the day. Even a disconnected panel on a cloudy day has the potential to provide a shock. However any electronic components should be sealed within the panel making it safe to clean. If in doubt you should contact your supplier.

Safety first:

If you decide that you want to maximize your energy outputs by cleaning your solar panels, make sure to keep yourself safe doing so. If you’re happy with “good enough” then sit back and enjoy having to do very little to keep the sun dropping your energy bill over the next few decades!

What about the inverter?

The solar panel inverter has an expected life of around 10-15 years and could potentially be the first thing that needs replacing or repairing. While you might think that’s your chance to break out your toolbox, the inverter is a box full of wires and circuit boards and unless you REALLY know what you are doing (we definitely don’t!) you’d best leave it to the professionals. If you’re concerned about the performance of system, try recording the output from the generation meter at regular intervals and contact your supplier with any concerns. The average cost of a replacement inverter is around £500-£1,000.
 

Image: Brian Kusler
 

More information about Solar Electricity on YouGen.

Find a solar PV installer

Need help with any Jargon?

If you have a question about anything in the above blog, please ask it in the comments section below.

Like this blog? Keep up to date with our free monthly newsletter

Comments

3 comments - read them below or add one

NEF Gordon

NEF GordonComment left on: 11 April 2016 at 2:13 pm

A note from a SuperHomer (Neil) with a solar pagoda at his house on this topic...

"I noticed a 2kWh difference in a day from cleaning my panels at peak in the summer last year. I deliberately chose 2 consecutive days where the forecast was for virtually unbroken sunshine. Until then, I had not cleaned my panels, so will be keen to see what the annual numbers are this year - I plan to clean them more frequently.

This got me thinking - could this be something we could undertake a survey about and start gathering numbers, perhaps from some who don't/can't clean their panels easily, some who can/do, and perhaps vary the regularity. This coupled with a general sample of data and tracking by region and age of PC installation, to see if the benefits of PV do track manufacturers estimates?

I know the TnCs state we should not alter our systems. Mine does not get close to its peak load now - I'm lucky to see 3.3kw whereas I regularly got above 3.7kw in year 1. This clearly has an impact over time and might explain the loss of annual yield after year 1.

I would appreciate your thoughts."

report abuse

morrisok

morrisokComment left on: 18 March 2016 at 11:34 am

I looked into this recently and decided to DIY, not 100% sure it helped but as far as I am concered even a small increase in efficiancy pays for itself if you have bought the equipment.  I am not sure I agree with using tap water though (garden hose). 

I wrote about it here and my tip is to use RO water from aquariam shops, its "pure" water on the cheap.

Happy cleaning all.

Kevin

report abuse

TerryS

TerrySComment left on: 16 March 2016 at 8:09 am

Whereas I can agree with the idea that too much interaction with the solar panels might easily result in them being damaged, I somehow disagree with the opinion that they don't require regular cleaning because the rain takes care of the majority of the dust, litter and such. Rain can actually leave your solar panels even more dirty that before, depending on your area. Besides, it usually leaves the panels full of spots and marks which isn't very good for them either.

Anyhow, some pretty good advice here :) Thank you for sharing, I bet many people will find it useful.

- Terry

report abuse

Leave a comment

You must log in to make a comment. If you haven't already registered, please sign up as a company or an individual, then come back and have your say.