Why rooftop solar panels need regular maintenance

When a solar panel maintenance service provider attended to a client’s place in Chennai, they were surprised to see big branches of a tree blocking the photovoltaic panel so much that it was affecting the efficiency of electricity generated.

That’s the least of the obstacles solar panels placed on the terrace face. Layers of dust accumulated over months, bird droppings, and equipment faults can significantly reduce its efficiency. A recent study by the Council on Energy, Environment and Water (CEEW) found that only half of rooftop solar (RTS) adopters monitor daily system performance and two-thirds clean their panels at least once a month.

A well-maintained RTS installation is said to take care of the energy needs for at least 25 years. Debanjan Bagui and Prateek Aggarwal from CEEW, who co-authored the study, say that while the current policy mandates five years of free maintenance support for RTS systems, the scope of the free services is not clearly defined. Therefore, the support provided during this period often differs from expectations.

Maintenance costs are embedded in the installation cost, with no explicit mention of cleaning services as part of the maintenance offered. When panels are not cleaned and maintained properly, the deposits can create hotspots that overheat and damage solar cells, causing permanent module degradation.

A poorly maintained system slows electricity generation, reducing savings on electricity bills and revenue from surplus energy exported to the grid, directly impacting financial returns. In worst-case scenarios, electricity bill savings over the RTS’s operational lifetime may decline to zero, while the payback period (the time required to recover the initial investment through savings) may extend beyond 25 years, says the report.

An ill-maintained RTS system also affects the discoms and government as well. For RTS adoption to be scaled, it needs to be matched with reliable, affordable, and accessible maintenance services.

Poor awareness about AMC

Vinoth Kumar, service manager with a solar company, says awareness about the annual maintenance contract (AMC) is poor among households that have invested in solar. Industries are still ready for an AMC. “When you take up a Central or State Government project, the tender has a clause mentioning AMC that usually covers 10 years,” says Vinoth Kumar.

The other challenge this sector faces is getting skilled labour to take up solar maintenance on a regular basis. Cleaning of panels is just one part of the work.

“We look for those with an ITI background, as the technician is supposed to check the functioning of the inverter and fuse, identify the hotspot area, see whether any cables are burnt and if MC4 connections are intact, etc,” says Vinoth. While a basic clean-up of the panel once a month is recommended, a visit by a technician once in three months is ideal.

Follow the SOPs

The report recommends that the Ministry of New and Renewable Energy (MNRE) to issue a standard operating procedure (SOP) on RTS maintenance, highlighting the scope of services, minimum frequency of visits, and service quality standards to be provided during the free maintenance period, along with manufacturer and developer responsibilities in case of panel damage or failures during the warranty period. The SOP could apply only to new installations.

Guidelines on basic do’s and don’ts for self-cleaning and automated alerts to nudge consumers are a few other best practices that can be followed.

The authors suggest tapping into the maintenance market. Like the national RTS portal as a one-stop platform to streamline the consumer experience and application process, maintenance services could also be integrated under the same platform. Discoms, or state nodal agencies, can act as trusted intermediaries rather than delivering services directly.