Solar O&M in India: Why Preventive Maintenance and Panel Cleaning Now Decide Project Returns

Introduction

India's solar industry is currently at the point where project success is no longer just based on how reliable the capacity is when the project is done. Solar systems now operate beyond their expected lifespan, which underlines the importance of maintenance in terms of generation, costs of operations, and profitability.

Dust buildup, faulty inverters, imperfection in wiring, loose connections, and unexpected downtime can cause problems in energy generation. Although individually, these problems don't sound too serious, taken together they can hurt the amount of energy produced and diminish project performance. Thus, preventive maintenance and timely cleaning of panels are becoming more important than before.

SolarPower Europe together with the National Solar Energy Federation of India (NSEFI) have developed India-specific O&M guidance, which consists of maintenance practices in line with India's operating conditions. The organizations had also created separate EPC best practice guidelines, which focus on project quality and occupational wellness. In combination, these guides provide a useful reference for different groups, including developers and asset owners interested in enhancing the reliability of solar projects.

Why Solar Panel Cleaning Matters in India

Dust and soiling are enduring challenges in the operations of solar plants in India. Factors such as dry climate, airborne dust, farming dust, construction activities and bird droppings may become layers of dirt on the modules and obstruct sunlight to reach the panels.

Impacts of dust can vary from location to location, depending on the weather conditions and design of the power plants as well as the type of dirt falling on the modules.

Cleaning schedules for utility-scale projects in Rajasthan and Gujarat as well as installations in urban and industrial areas must be based on the real conditions of the facility because a cleaning schedule set in advance can lead to cleaning in unsuitable conditions and resulting energy losses.

A paper published in Solar Energy in April 2025 written by researchers titled Estimation of non-uniform soiling loss in a utility-scale PV plant in India and strategies for enhanced performance through optimal cleaning schedules studies the patterns of soiling on the solar plants through the data collected at the level of solar strings.

An important operational consideration highlighted within the study is that soiling might not impact all components of the solar system equally. Monitoring performance at a more segmented level allows operators to determine where cleaning will be most beneficial rather than applying the same approach to cleaning all of these components.

Thus, for project owners, the situation is simple: is the surplus energy recovered by cleaning worth the costs related to this cleaning?

Preventive Maintenance: Finding Problems Before They Affect Generation

Panel cleaning addresses only one part of solar plant performance. Preventive maintenance covers the wider system, including inverters, electrical connections, cables, mounting structures, monitoring equipment and other balance-of-system components.

Operators can determine upcoming faults before significant downtime occurs and costly repairs are needed via a systematic maintenance program. Thermal imaging methods, electrical testing, inverter evaluations, etc. can help detect abnormal working situations, excessive heating, insulation failures and construction issues.

Vegetation growth, shading, intrusion of water, corrosion, etc. should also be considered in maintenance. Keeping records of inspections and faults will help find the equipment that should be paid more attention.

For large solar parks, these activities are particularly important because a fault affecting one component may reduce generation across an individual string, inverter block or a larger section of the plant. Early detection can limit the duration and cost of disruption.

Preventive maintenance also needs to be distinguished from corrective maintenance. Preventive work is planned to reduce the likelihood of failure, while corrective work addresses faults after they occur. A well-designed O&M programme combines both, with the balance depending on equipment condition, contractual requirements and the cost of downtime.

The Business Case: How O&M Protects Project Returns

Solar project economics depend on generating the expected volume of electricity while controlling operating expenditure. When cleaning is postposed and equipment is kept unrepaired, a project loses generation but still needs to keep incurring fixed costs.

For example, if a fictitious 10 MW solar installation loses 2% of its annual output due to avoidable cleaning and maintenance difficulties, this means losing 320,000 kWh if the output is expected to be 16 million kWh per year.

This is an illustrative calculation, not an estimate of typical losses across Indian solar plants. Actual results depend on location, generation forecasts, tariffs, contractual arrangements and the proportion of losses that maintenance can recover.

The calculation nevertheless demonstrates why O&M decisions should be evaluated against energy recovery and avoided downtime, not just the cost of hiring a service provider. An inexpensive maintenance contract may prove costly if it fails to detect faults promptly or maintain the plant’s expected performance.

Project owners should therefore assess maintenance expenditure alongside generation data, equipment availability, recurring faults and the financial value of recovered electricity. This makes it easier to determine whether a proposed intervention offers a meaningful operational benefit.

From Fixed Cleaning Schedules to Data-Driven Maintenance

The future of solar operations and maintenance (O&M) lies in its movement towards using practices that revolve around performance-based and data-informed methods.Unlike adhering to fixed time frames for solar panel cleaning procedures, currently used gadgets allow solar operators to keep track of weather forecasts, generation indicators, soiling assessment and trends of performance ratios.

An article published in Energy for Sustainable Development journal in June 2026 titled Opti-Clean: a predictive solar power systems framework for efficient PV panel cleaning describes a data-based cleaning framework that has been applied to a 24 kw solar facility in Delhi. The framework calculated environmental conditions such as the quantity of suspended particles and the wind speed, and produced forecasts of dust accumulation and energy losses, which enabled quick implementations of the forecasts in the cleaning actions.

The findings illustrate how local environmental data can inform maintenance schedules. However, results from a particular installation and modelling framework should not be assumed to apply directly to every utility-scale plant.

For larger installations, monitoring platforms can help maintenance teams compare actual generation with expected performance, identify underperforming sections and prioritise site inspections. Automated alerts can also help teams respond to inverter failures and other faults before they remain unresolved for extended periods.

The objective is not to clean panels less frequently in every situation. It is to determine the appropriate cleaning frequency and maintenance intervention for each site, balancing recovered generation against cost, water availability and operational requirements.

Water Efficiency and New Solar Cleaning Technologies

Another consideration worth mentioning is water availability, especially in areas suffering from lack of water resources. Regular wet cleaning operations require water. The amount of water needed will depend on the size of the PV plant, panel layout, cleaning frequency, installations, and other site-specific factors. It is advisable to study actual site operations instead of taking the average number.

Now, operators are also considering alternatives to regular wet cleaning methods, including robotic systems, mechanisation, and dry cleaning options. The effectiveness and efficiency of these methods depend on the type of method, location, and terrain. Therefore, it is important to distinguish between two types of automatic cleaning procedures: dry and wet robotic cleaning.

Cleaning methods must also be compatible with module manufacturers’ instructions. Abrasive materials, unsuitable water quality and inappropriate cleaning pressure can damage module surfaces or compromise warranties. Work on rooftops and elevated structures requires suitable electrical precautions and fall protection.

The most effective approach is one that restores performance without introducing avoidable water, labour, safety or equipment costs.

What Lies Ahead for India’s Solar O&M Market?

The next stage of solar project management will place greater emphasis on operational performance throughout an asset’s life. As project owners focus on predictable generation and cost control, preventive maintenance, effective cleaning strategies and reliable performance data will become increasingly important in managing solar assets.

Technology alone will not solve every operational challenge. Cleaning systems need to suit local conditions, monitoring data must translate into timely action, and maintenance contracts must establish clear responsibilities. Projects that integrate these elements into their operating plans will be better positioned to manage avoidable losses and protect long-term asset value.

For solar developers, asset owners and O&M providers, the central consideration is no longer simply whether maintenance is being performed. It is whether the maintenance programme is helping the plant generate electricity reliably, safely and cost-effectively.