Solar panels are a significant investment and keeping them clean is essential for maintaining peak performance. Environmental factors, site location, and industrial exposure can all contribute to dirt accumulation, making regular maintenance crucial. In this guide, we explore the tell-tale signs that it’s time to clean your solar panels, the risks of neglecting maintenance, and the best cleaning practices to maximise efficiency.
What Are the Key Indicators That My Solar Panels Need Cleaning?
There are a few clear signs that indicate when it’s time to clean your solar panels:
- Declining System Performance: If your solar system starts underperforming, particularly during peak afternoon hours, the first checks should be on the inverter or meter. If these components are working correctly, dirty panels are often the culprit.
- Location-Specific Factors:Sites surrounded by trees tend to accumulate dirt faster due to bird droppings and pollen. Similarly, commercial locations near factories or industrial zones may experience higher levels of dust and chemical residue. If the site is a factory, what it produces will impact how quickly the panels become dirty–for example, our customers Krispy Kreme and Darrell Lea need their rooftop solar arrays cleaned more often due to the vaporised sugar emitting from their facilities!
- Persistent Dirt Buildup: Any debris that rain cannot easily wash away should be considered alarming. A prime example is lichen growth on rooftop panels, which spreads rapidly and can significantly impact energy production if not addressed professionally.
What Kind of Dirt Requires Immediate Attention?
Certain types of dirt and debris can pose serious risks to your solar panels:
- Chemical Buildup: Some commercial sites, such as metal recycling factories, can experience a layer of chemical residue on panels. If not cleaned professionally, these chemicals can cause long-term damage.
- Lichen Growth: Lichen, a combination of fungus and algae, thrives in environments where natural elements alone are not strong enough to eliminate it. Left unchecked, it spreads rapidly and significantly reduces system efficiency.
- Bird Droppings & Heavy Pollen: Unlike dust, these substances create stubborn coatings that block sunlight and lower energy generation.
When is the Best Time to Clean Solar Panels?
To maximise efficiency, it’s important to time panel cleaning strategically:
- Autumn to Spring: Cleaning before peak summer months ensures optimal energy production during the highest-demand season.
- After Long Dry Periods: In regions with minimal rainfall, dust and dirt gradually build up, requiring manual cleaning.
- After Heavy Storms: Wind and rain can deposit debris, including leaves and bird droppings, necessitating a thorough clean.
Step-by-Step Guide to Cleaning Solar Panels
For systems under 100kW, manual cleaning is viable, while systems over 100kW benefit from robotic cleaning for consistency and efficiency.
Robotic Cleaning for Large-Scale Systems:
- Automated robotic systems ensure consistent cleaning and eliminate human error.
- Waterless robotic cleaners are available for water-restricted areas.
- Soft-bristled robotic scrubbers are effective in removing lichen and organic growth without damaging the panels.
Beyond cleaning, ongoing maintenance plays a crucial role in ensuring your solar system operates at peak efficiency. With a comprehensive approach to Operations & Maintenance (O&M), we at Smart Commercial Solar help businesses stay ahead of potential issues, maximising long-term performance and return on investment.
Maximise Your Solar ROI with Professional Maintenance
Ensuring your solar panels remain clean is a simple yet crucial step in ensuring consistent energy production and long-term system efficiency. Over time, even minor debris accumulation can reduce output, affecting financial returns and system longevity.
By adopting a proactive approach to maintenance—whether through routine inspections, professional cleaning, or advanced robotic solutions—businesses can protect their investment and optimise performance. With the right upkeep strategy, solar energy remains a reliable and cost-effective asset for years to come.
Special thanks to Christoph Beluz, Head of Operations and Technology at Geckon, for sharing valuable firsthand insights that helped shape this discussion.