How to maintain a solar power system
A guide to commercial solar power system maintenance is provided by Energy Matters.
The decision to install a commercial-scale solar power system has been a wise choice for many businesses. In addition to enhancing a company’s credibility on a sustainability front, rapidly increasing electricity prices mean a commercial-scale solar panel array can have a significant positive impact on a company’s bottom line.
While a solar panel has no moving parts and a good quality system in its entirety is very robust – requiring little outlay in terms of care – by ensuring recommended maintenance and monitoring is carried out, the performance of a system and its expected service life can be preserved.
DAILY SYSTEM CHECKS
Daily system checks usually involve casting an eye over reports generated by the automated monitoring system. A good quality monitoring system will show detailed system output data and flag any issues. All of this detail should be accessible via the manager’s desktop computer, notebook or smartphone, rather than having to physically inspect the array and inverters.
Some monitors will also interface with a building management system and, depending on the configuration, set off alarms if a problem is detected that can be sent via email or SMS to the system manager.
While solar panels are generally self-cleaning, dust may accumulate in areas experiencing high dust levels and little rainfall, and this can have an impact on system performance.
The cleanliness of the modules should be verified every three months – check for accumulation of debris, dust or fungus on, around and/or under the array. There should also be a check to ensure that no shading of the array is beginning to occur; for example, due to surrounding tree growth.
ANNUAL SYSTEM MAINTENANCE
While the system owner can carry out some of the following annual system maintenance checks, we recommend the following be performed by a suitably qualified person each year.
- perform a general check of performance over the year by referring to the available automated monitoring data or on-site records.
- clean panels to retain optimum performance
- check panel mounting hardware
- visually inspect for any damage to the panels – fractures, browning, moisture penetration or frame corrosion
- check conduits and all cabling are protected and secure
- check voltage of each string is within the manufacturer’s tolerances
- check earth connection for continuity, and
- if accessible, inspect junction boxes for tightness of connections, water accumulation/build-up, integrity of lid seals, integrity of cable entrance, glands and/or conduit sealing, integrity of clamping devices and, if external, verify bypass diodes.
Other junction boxes
- check the tightness of connections, water accumulation/build-up, integrity of lid seals, integrity of cable entrance and/or conduit sealing, and integrity of clamping devices
- if applicable, check blocking diodes and surge arresters for degradation, and
- check connections for tightness of connection and corrosion.
- visually inspect fuse boxes for any damage or water ingress, and
- check fuses and connections for resistive joints.
- visually inspect breakers/isolators for any damage
- check breaker and connections for resistive joints
- measure open circuit voltages and short circuit currents, and
- verify the operation of isolation devices.
- visually inspect inverters for any damage
- check connections for resistive joints
- check the DC voltage applied to inverter input, and
- ensure that there is free space around the units for cooling purposes.
- check the alignment and rigidity of the framing system, and
- check for loose fittings.
Every five years, the mechanical integrity of conduits and cables installed without conduit should be confirmed, and the framing/mounting system should be inspected for corrosion.
MAINTENANCE TIME INVESTMENT MINIMAL
While all the above may sound quite time-consuming, a 10-kilowatt solar panel system’s yearly maintenance, including daily monitoring, involves fewer than a dozen hours annually. A 50-kilowatt system only represents an 18-hour investment per year in maintenance and monitoring activities. Systems larger than 100 kilowatts will, however, require some extra maintenance tasks not mentioned above and, therefore, an increased investment of time.
All in all, solar power offers a viable way to produce cheap electricity that requires little in the way of maintenance.
One of Australia’s longest established companies purely focused on solar panel systems, Energy Matters has installed over 15,000 solar PV systems, including commercial-scale arrays for Australia Post, Johnson & Johnson, NEXTDC and Dexus Property Group.