Many customers ask, “Do I need to clean solar panels?” Third-party companies often obtain lists of solar panel owners and contact them, claiming regular cleaning is essential for efficiency. However, is professional solar panel cleaning necessary, or is it unnecessary?
Understanding the Cost vs. Benefit of Cleaning Solar Panels
Yes, solar panels can be cleaned, but homeowners should consider whether the cost justifies the potential benefits. If done professionally, cleaning services typically range from $150 to $200 per session, sometimes even more. However, the additional energy generated from cleaning does not usually offset the expense.
For example, in Las Vegas, electricity costs roughly $0.12 per kWh. If a homeowner spends $200 on professional cleaning, they would need to generate at least 1,660 additional kWh to compensate for the cost. However, solar panels do not produce that much additional energy simply because they are cleaned.
Additionally, companies specializing in solar panel cleaning often recommend cleaning panels at least twice a year. This would bring the total annual cleaning cost to approximately $400, requiring over 3,300 additional kWh of energy production annually to break even. This level of energy gain is simply unrealistic.
Risks of DIY Solar Panel Cleaning
For those with a one-story home, cleaning solar panels independently is an option. However, it is never recommended that anyone climb onto the roof to clean their panels. The falling risk is significant, and no cost savings are worth the potential danger.
If a homeowner chooses to clean their solar panels themselves, it is crucial to follow the manufacturer’s guidelines to prevent damage1:
- Do not scratch off dirt. Use a soft cellulose cloth or sponge to wipe away stubborn dirt gently. Avoid microfleece wool or cotton, which may cause scratches.
- Rinse with lukewarm water. This effectively removes dust, leaves, and other debris without causing damage.
- Use an alcohol-based glass cleaner. Avoid abrasive detergents or surfactants, as they may degrade the panel surface.
- Apply isopropyl alcohol (IPA) selectively. It can remove stubborn stains or dirt within one hour of their appearance.
- Avoid using high-pressure washers. Excessive pressure can damage the panels and reduce their effectiveness over time.
Is Cleaning Necessary?
Many homeowners find that cleaning their solar panels is unnecessary. For example, a homeowner with solar panels for 11 years has relied solely on occasional rain in Las Vegas to keep them clean. Despite this, they have not noticed any significant decrease in energy production. Some years, as observed in their monitoring app, they have produced more energy than the previous year.
Given this, paying $400 per year for two cleanings may not be worth it, especially when considering that just a few days after a professional cleaning, the panels will likely look the same as they did before.
Final Thoughts
While solar panels can be cleaned, the cost-benefit ratio should be carefully evaluated before hiring a professional service. The slight increase in efficiency from cleaning often does not justify the expense. Homeowners with single-story houses may clean their panels themselves, following proper guidelines to avoid damage. However, in many cases, natural rain is sufficient to keep solar panels functioning efficiently.
Ultimately, solar panel cleaning is not a necessity for most homeowners, and the decision should be based on personal circumstances, climate, and the system’s specific performance over time.
