As you will be knowing by now, solar PV power plants require only a small amount of maintenance. But that does not imply no maintenance.

The usual O&M activities in a solar power plant are listed below:

  • Module Cleaning – Cleaning the panels in order to get rid of dust and other debris accumulated over time is an absolute must. The panels are to be also checked for any sort of cracks and other mechanical defects. A cleaning routine of once every two-three weeks (could be less in a region with high rainfall) is considered optimal.
  • Inverter Maintenance – Output from inverters should be more or less continuously monitored by the O&M team. The maintenance team usually ensures that the there are no loose wires or cables from or to the inverters, and also looks out for any loose nuts or bolts once every month. They also are expected to make sure that there is no dust or dirt accumulation on the inverters.
  • Maintenance of Cables and Combiner Boxes – Visual inspection of all the cables and combiner boxes is ideally done once a week. Similarly, visual inspection will detect any insulation failure in cables or corrosion issues in combiner boxes.

 

  • Maintenance of Civil and Structural Sub-Systems – One of the tasks of the O&M personnel will be to make sure that the growth of shrubs and other vegetation are kept in control. As part of routine inspection, the O&M personnel also usually check out for any misalignment or bends in mounting structures.
  • Maintaining the battery pack (in case you use batteries for your rooftop solar power plant) – This includes weekly cleaning of battery terminals and ensuring all connections are tight. Battery maintenance also includes routine checking of electrolyte levels and recharging them at regular intervals.

How much could these O&M activities cost?

The cost could differ across installations owing to differences in the frequency in which such maintenance is done, and also owing to the different labour costs in different regions.

For rooftop solar power plants, the cost could be a lot lower (less than Rs 500/kW/year) if existing office or factory personnel are used for cleaning and maintenance.

The benchmark costs for maintenance of large solar power plants can be taken as Rs 5 lacs/MW per year and for small and medium rooftop solar power plants at about Rs 1000/kW per year.

 

Stuff to Remember

The O&M costs for solar power plants are low, with typical O&M expenses in India being only about 1% of the total capital cost.