Strategies to Reduce Solar Panel Cleaning Costs

The growth rates for solar in the last 5 years have been double-digit. As each solar panel goes up, however, so does the need for solar panel cleaning maintenance; yet the growth of solar maintenance technicians has not matched demand. This gap creates a significant issue in the supply chain and drives up the cost of solar panel cleaning services. What can solar asset managers do to improve their supply chain and optimize the costs of solar panel cleaning?

Hidden costs 

The field of PV soiling management is new and constantly evolving. Many solar asset managers may know something about solar panel cleaning, but few are experts. Understanding the hidden costs of solar panel cleaning is key to optimally managing nationwide or regional projects. 

Jobsite learning curve

The cleaning crew can improve their productivity by 20-40 percent by understanding the site and its associated challenges. The more a solar panel cleaning crew knows the site, the faster they can service it. If you change crews regularly, each crew must relearn their way around the site.

Equipment optimization

A multi-year contract allows the cleaning company to invest in the optimal equipment for your site, reducing production times by 20 percent or more. For example, the following conditions were listed to obtain a quote:

• 8000 solar panels - The asset owner did not have the dimensions of the solar panels.
• Fixed Tilt Ground Mount
• Water onsite but not near panels
• 4 module landscape configuration solar.
• High soiling levels and “caked-on” conditions due to no rain in the last 170 days
• Very narrow rows but width not available.

Equipment options for this site included:

1. Rotary Brush 
2. Lift and Shift System

Ideally, this site would be cleaned with a Lift and Shift system that allows you to do approximately 3 MW+ per day, but due to the atypical configuration of the panels, a custom lift and shift system was needed. Since a recurring contract was not an option, the area's solar panel cleaning service companies only offered to clean with a powered rotary brush or a non-conductive water-fed pole system. These systems can clean approximately 0.5 MW per day. 

Rotary Brush vs Lift & Shift System

Unexpected costs due to accidents or negligence

Working with a certified solar panel cleaning company trained in safety will avoid accidents and other events that can bring unexpected costs to the solar O&M budget. The North American Board of Certified Energy Practitioners (NABCEP) offers three solar panel cleaning safety courses.                                                                                                          

Solar Panel Cleaning Safety (2 credits)

Solar Panel Cleaning Safety for Residential Installations (4 credits)

Solar Panel Cleaning Safety for Commercial and Utility-Scale Solar Installations (9 credits)

Solar panel cleaning technicians should be trained in solar panel cleaning safety. Ideally, the company providing the service offers the following:

• Pre-Cleaning Safety Inspection by Certified NABCEP - PV System Inspector
• Solar Panel Cleaning Services
• Advanced Reports
• Interactive online reports and high-res PDFs
• JHA
• Safety Leader On-Site

How can solar asset managers bring down the cost of solar panel cleaning? Design sites with optimal PV soiling management features.

The best way to drive the cost of solar panel cleaning to optimal levels is by including the “PV soiling management system” in the project's design phase. Designing for solar maintenance brings 30 years of value, and solar panel cleaning is one of many concepts to include in the design phase. Each solar site is unique, and how a site is maintained is specific to each site. Here are some high-level pointers: 

1. Water on-site
2. Design for safety
3. Improved accessibility for solar panel cleaners
4. Optimal solar panel cleaning equipment
5. Human capital - do we have resources in the area that can service the installation, and if so, how many?

Give your solar panel cleaning company a multi-year contract with recurring cleanings.

Solar is growing at double-digit rates, yet the creation of professional solar panel cleaning technicians is not. This gap causes solar assets to underperform and pose risks. 

Multi-year solar panel cleaning contracts will encourage contractors to:

• Professionalize
• Buy optimal equipment for each site they service
• Invest in knowing the site thoroughly so they can be more efficient

Plenty of people can and want to work in a good job, but the lack of reliable cash flow often deters this group of people from investing in getting credentials. The gap between demand for and supply of professional O&M technicians causes solar assets to underperform. This can be prevented with good contracts and best practices that foster safety and promote investment for reliable growth.

Carla Dawson teaches solar panel cleaning safety, quality, and technology via Soilar.tech. She is an advisor to SEIA, NABCEP, SPCFonline.com, and ASTM. Dawson is also VP of product development at Sol Clarity. She is an Industrial and Systems Engineer with an extensive B2B technology product management background.

Soilar Technologies | https://soilar.tech