Preventive maintenance on solar power plants

There are 4 common types of maintenance: corrective maintenance, preventive maintenance, risk-based maintenance and condition-based maintenance. The solar panel cleaning robot from SolarCleano is one of the key elements of predictive maintenance for solar power plants.

What is preventive maintenance?

Preventive Maintenance, also referred to as PM, is a proactive maintenance strategy that involves regular and routine maintenance of equipment to reduce the likelihood of failure leading to unplanned downtime. Through scheduled cleaning, repairs, adjustments, and part replacements, a preventive approach increases the availability and operational output of equipment and machinery.¹

Specifically, solar panel preventive maintenance focuses on testing regularly electrical connections, controlling the status of the panel’s fixations and the good general state of the solar panels. Solar panel manufacturers give specifications as to how to inspect a solar installation, and large-scale power plants dedicate team to these inspections so as not to run any risk of failure. If any of these test yield issues or raise concern, corrective measures will be undertaken.

What are the risks of not using preventive maintenance on solar power plants?

For many years, it was commonly believed that solar panels do not need any cleaning. Their natural inclination and precipitations would result in an automatic cleaning. Measurements however show that the energy output of solar panels reduces drastically when they are left uncleaned. This is particularly visible in dusty, arid and windy areas, as the wind blows sand on the panels.

However, even in milder conditions, with rainy weather and an inclination that helps water to flow downwards, it is noticeable that dried dirt remains on the panels. Moreover, it tends to become engrained dirt and stay on the panels for a longer amount of time.

While shade on the panels temporarily diminishes their production, dirt will keep production down permanently. On any size plant, the accumulated dirt on the panels within a year, can lead to a productivity decrease anywhere from 1.5% to 30%.
In some desertic areas, even higher productivity decreases were noted.

Without routine maintenance, the probability increases for a larger issue to arise, which could substantially impact the overall production or the safety of the system.²