How to Clean Solar Panels

If you want to maintain the best performance, you need to maintain clean solar panels. Often, solar panels accumulate pollen, dust, sea salt, and pollution. If there are elements in the air, expect them to build up on your panels eventually.

Additionally, if your panels are located near freeways, factories, highways, or airports, they have an increased tendency to build up more grime, dirt, or oil, which affects their efficiency. Notably, not cleaning your panels effectively can affect their efficacy by about 15-25%. For this reason, it is crucial to know the best way to clean solar panels. Let’s get started.

Step-by-step Guide on How to Clean Solar Panels

cleaning solar panels

Step 1: Shut Down Your Entire System

The first step in how to clean solar panels safely guide is to ensure you shut down the entire system. Follow the shutdown procedure indicated in the manual. You can also check the inverter manufacturer’s operating manual for guidance. Ensure the DC or direct current systems are fully shut down. For the AC systems, you can use the solar supply main switch to shut them off.

Step 2: Block-Off or Disconnect Gutters or Rainwater Collections

If you have rainwater tanks installed in your home or connected to your gutters, you need to disconnect them temporarily. This ensures dirty run-off water does not go into your clean water tanks.

Step 3: Choose the Best Time

When learning how to clean solar panels on the roof, choosing the best time of day is important. When you combine the hot glass on the panels with cold water, you can cause cracks due to sudden temperature changes. Moreover, when the sun is brightly shining, it can cause any water you pour on the panels to dry out quickly and leave dirty marks.

It is crucial to choose a cool time of day, such as the early morning. Additionally, the dew that settles on the panels overnight can help soften the dirt, making the cleaning process easier. If it’s impossible to clean the panels early in the morning, you can do so during a mild or cool evening or an overcast day.

Step 4: Clean the Panels from the Ground

One of the important tips to consider when cleaning your solar panels is doing so from the ground. It is safer. To do so, use a hosepipe and direct the water on the PV solar panels. Ensure you choose a suitable nozzle that can allow the directed water stream to reach the solar panels.

Step 5: Direct Water to the Top of the Panels

Though clean solar panels’ efficiency is much higher, you need to clean them properly to avoid damages. You need to ensure you only direct the water onto the top of the panels. Some water may touch the back of the PV modules during the cleaning process; however, you need to avoid it getting into the gap between the panels and the roof.

Step 6: Use Mild Soap and Soft Cloth

In the cases where your panels have an accumulation of grime and dirt, you can use a soft cloth and mild soap during the cleaning process. You can also use a good-quality soft brush, a plastic blade, or a cloth-covered sponge. Adding a long extension code can help you clean the panels safely from the ground.

Once you remove the stubborn grime and dirt, rinse off the panels using clean water. Ensure all the used soap is washed off completely and dry out the panels. Air dying the panels prevents any residue water or soap streaks from accumulating.

Step 7: Use Appropriate Safety Equipment if You Want to Climb on the Roof

It is not always possible to clean solar panels from the ground. If you need to go up the roof to do a good job, ensure you wear the appropriate safety equipment. Remember, the risk of going up the roof increases when you are using water and soap. It can become extremely slippery. In such cases, it is best to hire a professional to do the job if you do not have the appropriate equipment.

Step 8: Hook your panels back up & turn them on

Once the panels dry completely, you can now switch the system on at the inverter. Then, confirm if everything is working appropriately.

What to Avoid When Cleaning Solar Panels

When looking for tools to clean solar panels, it’s good to remember that some can do more harm than good. Therefore, you should avoid:

  • Hard water because it leaves residue on the panels that can reduce their efficiency.
  • Abrasive sponges can scratch and damage the panels.
  • High-pressure water because can cause damage to the panel frame. Use moderate temperature when cleaning the panels using a nozzle.
  • Freezing water can lead to thermal shock, permanently destroying the panels. Use water that closely matches the panel’s temperature.
  • Detergents and solvents can cause damage to the solar collector’s surface. 

Frequently Asked Questions

1. Do You Need to Clean Solar Panels?

Cleaning solar panels is crucial for maintaining their efficiency. Solar panels accumulate dirt over time which blocks out sunlight from reaching the solar cells. As a result, the photovoltaic output reduces. Additionally, leaving such residue on the panels for long degrades them. Clearing solar panels:

  • Increases energy production and efficiency
  • Maintains the warranty as some companies add cleaning as a condition for replacement.
  • Improves lifespan.

2. How Do I Tell if My Panels Need Cleaning?

You can do so in two ways. First, physical inspection of the modules. When you look at the panels, you can tell if you should clear the solar panels. If they contain bird droppings, leaves, dirt, or dust, it’s time to get them cleaned.

Second, you can monitor the solar panels’ output. If you notice that their production has reduced, it can indicate that you need to clean the solar panels. However, if cleaning the solar panels does not solve the issue, you may need to call an expert to diagnose your system.

3. Does Rain Clean the Panels?

Rain can clean the solar panels; but, only to a certain degree. Rain can effectively rinse off fine sand or dirt. However, sometimes, something sticky gets on the panels, such as bird droppings which will require effort to clean off. In these cases, human labor is necessary to get clean panels.

4. Can You Clean Solar Panels with Windex?

Notably, different manufacturers have different guidelines regarding cleaning solar panels. Therefore, it is important to follow these requirements. When cleaning solar panels, it is not recommended to use abrasive cleaners or Windex. These additives can leave a residue that can degrade the ability to absorb light.

5. Can I Use Tap Water to Clean Panels?

Most manufacturers recommend that you use de-ionized water or distilled water when cleaning the panels. In areas where the tap water is hard, you cannot use it to clean the panels. You can purchase a hose attachment that can filter out minerals from the water. Hard water is rich in minerals, and it can cause damages to the solar panels.