by

Using Beach To Clean Solar PV Systems

Is it time to clean your solar panels and are pondering if bleach is a good cleaning agent to use?



Here’s a general rule that you should always keep in mind:

Solar panels are delicate and should be cleaned with a mild detergent(anything you can use for your dishes). Bleach, being a harsh chemical, should not be used to clean solar panels.

So, why is it unsafe to use bleach or any other strong cleaning fluid on solar panels? Which components of your solar PV module are at risk of damage by bleach? Read through this post to find out.

Don’t Clean your Solar Panels With a Harsh Chemical Like Bleach!

How does bleach damage your solar panels?

1. Chemical interactions

Bleach has around 6% chlorine. This chemical agent can cause harmful chemical interactions on the surface of the solar panels leading to damage.

2. Discoloration

Discoloration will generally occur when a low-quality Ethylene Vinyl Acetate film (definition on the next section) is exposed to water or UV rays.

Now imagine the kind of discoloration that’ll happen when bleach (which is by itself a discoloring agent) gets to these films. Discoloration significantly reduces the efficiency of solar modules.

3. Corrosion

Bleach can be corrosive to some metals and plastics. The abrasive nature of bleach, combined with the corrosive effect, can significantly damage your solar panels.

What Component of Solar Panels Will Bleach Destroy?

First, if you're not aware of what makes up your solar panels, here are the major components:

  • Anti-reflective coating- Allow maximum absorption of sunlight. This increases the output of solar panels and reduces glare problems, especially when solar panels are installed near airports.
  • Extruded, anodized Aluminum frame- This is the outer housing of the module. The frame increases mechanical stability and also protects the glass and encapsulant films.
  • Highly transparent tempered glass- The main protection for the solar cells from the weather or debris. This component is responsible for increasing the longevity of solar cells.
  • Encapsulant EVA(Ethylene Vinyl Acetate) films– These are inner films covering and protecting the solar cells.
  • Photovoltaic solar cells- This is where light to DC conversion occurs. A P-N junction is leveraged for electron flow.
  • Insulating back sheet- A moisture barrier, mechanical damage protection, UV blocker, and thermal stabilizer installed at the back of the solar module.

Back to our question:

Firstly, bleach will damage the anti-reflective coating. This will happen in form of direct abrasion or through chemical interactions.

Secondly, bleach can cause corrosion on the Aluminum frames. When you use bleach on your solar panels, it'll scraps away Aluminum oxide (a protective layer formed when Aluminum combines with oxygen), exposing the frame to outdoor elements and definitely, more wearing away.

Lastly, bleach will damage the encapsulating films (Silicon nitride or Titanium oxide). As mentioned in the previous section, the damage on these films will be in form of discoloration.

Well, it may be quite hard for bleach to find its way to the encapsulating films, but if this occurs, your PV module's efficiency will be greatly impacted.

No one would like to have low-performing solar panels. So, there's no need to use bleach when you know the kind of damage it'll cause to your PV module.

What other bleach alternatives are safe?

Now that we’ve invalidated bleach as a solar cleaning agent, does it mean that your solar panels should remain dirty?

Definitely not, and here are the best cleaning agents to use for your solar panels instead of bleach:

1. Plain water

Trust me, if you clean your solar panels frequently, water alone will always do the job.

2. Water and mild soap

This is the best and safest cleaning solution for cleaning dirt and grime off solar panels. By ‘mild', I mean anything that you can use to clean your dishes.

3. Vinegar

This is a natural cleaning agent and a great cleaning agent for solar panels. Check out our post on using vinegar to clean solar panels.

4. Isopropyl alcohol for oily stains

Use a little amount of rubbing alcohol if there're tough, stubborn oily stains on your solar panels. Note that this should be used as a last resort.

How not clean solar panels?

In addition to using bleach, here are other things to avoid when cleaning solar panels:

Using abrasive cleaning tools- Something like a hard brush can scratch and mark your solar panels.

Tip: Use a sponge, soft cloth/brush.

Using high pressure- High pressure will cause physical damage to your solar panels.

Tip: Use a normal hose with no pressure setting

Cleaning your solar panels when it’s extremely hot- The mixture of water and the cleaning agent may evaporate fast, leaving a smear that may interfere with the proper functioning of solar panels. If extreme temperature changes occur, your solar panels may even break or crack.

Tip: Clean your solar panels early in the morning or evening.

Accessing your roof without safety equipment- This puts you at risk of falls and injuries.

Tip: Use the right access equipment or hire a solar panel cleaning professional.

Using tap water- Tap water has a high mineral content that may damage your solar panels.

Tip: Use de-ionized water or attach a water softener to your hose.

Using non-specialized tools such as a broom or shovel when removing accumulated snow on your solar panels- This will scratch the anti-reflective coating, reducing the working efficiency of the panels.

Tip: Use a solar panel snow rake. It’ll remove the snow without damaging your solar panels. An even better solution is installing a snow guard to prevent snow from building up.

Takeaways

Bleach is not a safe cleaning agent for your solar panels.

Generally, if you use bleach on solar panels, it'll destroy the anti-reflective coating, meaning that very little light will be seeping into the solar cells.

This translates to low efficiency the last thing you'd want as a solar power consumer.

What's more, if the bleach comes into contact with the delicate encapsulating films and aluminum frame, it may cause damage in form of discoloration and corrosion, respectively, reducing the efficiency even further.

To be on the safe side, avoid using bleach on your solar panels, and consider the alternatives cleaning agents discussed in this guide.