Why clean solar panels on the roof?

Lets begin with the basics – panels are usually installed with the correct amount of tilt. This proves to be advantageous for self-cleaning the panels when rainwater runs across them. But in places that experience long periods of drought, regular cleaning of the panels is essential. The solar panels installed on the roof could build up dust and grime, along with the droppings of the birds. Apart from this, if there are trees located close to the panels, specifically the deciduous ones, the leaves shed by the trees can drop on the panels and attract birds as well. 

The panels on the roof can get dirty due to various reasons as discussed above. Some parts of the panel’s surface covered with dirt can reduce the total amount of current produced by the system per module. As the panels generate electricity by converting the sunlight incident on them, it is important for the panels not to be obstructed by any debris. 

Hence, cleaning the solar panels to ensure they work at their potential is important. 

How to clean solar panels on the roof?

Before starting the process, here is a list of materials required: 

Materials required

• An Extension Ladder
• Garden hose with a spray attachment
• soft brush or a sponge
• Squeegee attached to the extension pole
• One-gallon handheld sprayer
• Gloves
• Commercial cleaning solution or a soap solution

Cleaning the panels

Before cleaning the panels, it is advisable to contact the manufacturers to seek guidance on specifications for Do’s and Don’ts. The manufacturer can tell if the panels need to be cleaned with a specific method, and the type of cleaning solution suitable for the kind of panel. 

Here are the basic steps to clean the solar panels on the roof: 

1. Gather tools and materials: 

Ensure all the materials you need for cleaning are easily accessible. Set up the extension ladder and make sure it is safe to access the roof. While cleaning, get a buddy along with you to hold the ladder and hand the supplies when required. Prepare the cleaning solution and transfer it to the gallon sprayer for use.  

2. Turn off the system: 

Turning off the solar panel system before getting to the task ensures the safety of both the personnel and the system. 

3. Spray Down the Panels and Roof:

Make sure someone is holding the extension ladder on the ground tightly for you, only then climb to the roof height. Use a garden hose with a spray attachment to rinse off the panels and the surrounding roof to remove loose debris or dirt.

4. Spray Cleaning Solution: 

The gallon sprayer sprays a thin layer of cleaning solution on the small section of a solar panel using the gallon sprayer. Let the solution cut through the dust and grime for a minute or two. Take care it does not get dried up. 

5. Wipe Down the Solution: 

Using a soft brush or a sponge, wipe down the section of the solar panel where you had sprayed the cleaning solution. You can also use a towel to wrap around the squeegee on the extension pole if the area is beyond reach. While cleaning, take care not to lean over the panels and always maintain a standing posture on the ladder with flat feet. 

6. Repeat in Small Segments: 

As the panels are to be cleaned in small segments, repeat the steps from 1 to 5 to clean all the panels on the roof. 

7. Rinse the Panels:

Make use of a hose and spray attachment to rinse off the panels one last time. After rinsing off all the residual soap solution, use a squeegee to dry the panels before you turn the power on to the modules. 

Things to avoid While Cleaning Solar Panels

Here is a list of don’ts to avoid any mishap while cleaning the panels: 

• A pressure washer should be avoided as this can harm the glass on the solar panels. 
• Avoid spraying cold water on hot panels as it may cause the panels to crack. 
• Skip using any harsh chemical cleaning agent like bleach because it can not only damage the panels but also be harmful to the nearby wildlife.  
• Avoid using any rough cleaning instruments like abrasive cloths, sponges, or heavily toothed brushes to prevent scratching the surface of the panels while cleaning. 
• Never stand on the solar panels as the weight could cause them to crack and damage the panels. 
• Also, do not forget to inspect the panels routinely. This ensures the panels are free from any damage or cracks, and you can keep a check on the buildup of nests by birds or rodents. 

Regular inspection of panels can ascertain that the panels receive maximum sunlight and cut electricity usage. 

How often To clean Solar panels?

There is no such hard and fast rule for how often the panels must be cleaned. However, a good rule would be to clean the panels once or twice a year. Studying certain factors can help you outline the cleaning schedule: 

• Geographic Location: 

Rainwater can naturally clean the panels for you. But if you live in an area with a dry climate, there might be a need to clean panels more often. 

• Landscaping: 

The panels are installed at sites that have direct access to sunlight. If there are trees nearby in the yard, there is a high possibility that pollen, leaves, branches, and other kinds of debris may end up on the panels. 

• Pitch of the roof: 

Usually, the solar panels that are installed on roofs with steep pitches do not require cleaning as frequently as the solar panels on roofs with low pitches. 

problems when cleaning Solar panels

The solar panels need to be cleaned well to generate the maximum amount of electricity. There are several common problems encountered by people while cleaning. Here are the points of care listed: 

1. Safety Hazards: It is common to face accidents like slips and falls while cleaning. To avoid such accidents, use safety equipment like harnesses and have a buddy to assist you. It is important to take care while working on the roof. 
2. Damaging the Panels: The use of any abrasive cloth a harsh chemical, or a sharp tool can scratch the surface of the panel. This scratch leads to a reduction in the efficiency of the panel. Make use of soft materials like microfiber cloths and gentle cleaning solutions to prevent any injury to the panel. 
3. Damage due to water: If the panel is not well-dried before turning on the system, it can be potentially dangerous. Avoid using excessive water while cleaning to prevent any water seepage into the electrical components of the panel, as it can cause electrical issues or even a short circuit.
4. Wrong Cleaning agent: The wrong choice of cleaning solution can impair the protective coating on the panels. It might also degrade the solar panels over time. Therefore, consult the manufacturer for guidelines for choosing the right cleaning product. 
5. Wrong Time: If the panels are cleaned in direct sunlight or during the hottest hour of the day, it can cause the cleaning solution to evaporate quickly. This results in residues left behind. Hence, it is recommended to clean the panels either in the early morning or late in the evening when the temperature is much cooler. 
6. Lack of Routine maintenance: If the panels are not cleaned regularly, the buildup of dirt and other debris can significantly affect the efficiency of the panels in the long run.
7. Electrical Risks: While cleaning the panels with water, there is a risk of electrocution. You can wear rubber slippers to prevent any such unfortunate incident. You can also hire an expert to help with this risky task. 
8. Wrong Technique: Following the wrong techniques, like harsh scrubbing or using abrasive tools, can ruin the panels. It is of cardinal importance to follow the guidelines provided by the manufacturer or the professional installer to clean the panels. 
9. Ignoring the warranty guidelines: Some of the panel providers have specific guidelines for cleaning to maintain the warranty of the panel. If these guidelines are neglected, it might end up voiding the warranty and leaving you without the courage if needed to repair any damages in the future. 

When to Hire a Professional? 

The simplest, easiest, and most cost-effective method is to let the rainwater clean the panels naturally for you. However, in certain instances, there might be a need to hire a professional, such as: 

• If you live in a heavily polluted or coastal area
• If you have some deciduous trees near the solar panels. 
• If there is some tough buildup on the panels, like bird droppings
• It is difficult to clean the panels by yourself. 
• If there are time constraints 

You can hire a professional to clean and inspect the panels on an annual basis. It costs approximately $150 to clean and inspect the panels. If you just need the panels to be cleaned, it costs roughly $25/panel.

You can install a CCTV camera on the roof to inspect the panels instead of climbing up the ladder for this task.

Benefits of cleaning solar panels

1. Increased Efficiency: As cleaning the surface of the panels removes any obstructions on it, a greater amount of sunlight is incident on the panels. Hence, more light reaches the PV cells and thus increases green energy generation. 
2. Maximum Energy Output: More green energy production leads to energy independence. Also, the excess amount of energy can be sent to the grid if the panels are connected to it. 
3. Prolonged Lifespan: The average lifespan of a panel is 25 years. However, routine maintenance can extend the lifespan, giving you more energy for a lifetime. 
4. Maintaining warranty: To keep the warranty valid, some of the panel manufacturers require the regular cleaning of panels. By adhering to the maintenance requirements, you can maintain the eligibility for warranty coverage in case of any defects with the system. 
5. Optimized Performance: When the solar panels are cleaned well, they can operate at their highest capacity. Thus, it acts as a source of consistent and reliable energy. 
6. Environmental Impact: Solar energy is green energy and an efficient alternative to traditional fossil fuels. By using green energy, you can reduce the greenhouse gas load and help combat climate change.
7. Cost-effective: As you clean the panels, more energy can be generated by the panels for the same amount of light received. This can significantly reduce the electricity bills over time, thereby making the investment in panels worthwhile. 
8. Prevention of Hot Spots: The buildup of dirt and debris on the surface of the panels can cause uneven heating, leading to hot spots. These hot spots prove to be detrimental to the panels and lower their efficacy. Cleaning the panels routinely prevents any formation of such hot spots and confirms the panel performs properly. 
9. Enhances Aesthetics: Clean solar panels enhance the aesthetic value in comparison to dirty ones. As the panels are installed on the roof, they are visible from the ground or the neighboring properties; therefore, cleaning solar panels is important from this point of view as well.