by Jason Deign, Solarplaza

Italian solar leader believes it’s time for wind industry-style preventive maintenance to cut operations costs.

Stern Energy, a Parma, Italy-based firm, is joining forces with PV test and inspection leader Suncycle to bring about a new approach to solar operations and maintenance (O&M). The two companies are hoping to cut long-term PV plant O&M costs through preventive maintenance, a technique that has already been shown to cut the cost of O&M by up to almost 40% in the wind industry.

Preventive maintenance involves a modest increase in ongoing O&M yearly budgets to allow for greater data collection that can help head off the chances of major equipment faults and consequent significant loss of revenue. Stern Energy’s managing director, Stefan Torri, said minor increases in current PV O&M yearly budgets will have a similar kind of positive return to that seen in the wind sector.

“We are fighting hard to show O&M cost reduction is not a matter of saving a few thousand euros a year, but rather of increasing the quality of services with the aim of keeping the asset fully functioning for its lifetime,” he told Solarplaza.

The predictive maintenance concept has been developed in response to numerous situations where Stern Energy has been called in to solve unforeseen severe technical problems that investors were able to discover only at a late stage when production was already seriously affected, according to Torri. The added O&M expense for highly specialized predictive maintenance would work out at between €2,000 and €4,000 a year per megawatt. Torri compared the preventive maintenance approach to medical care where prevention has proven to be much more cost effective than cure.

“In Italy we have seen O&M services drop in price from a range of€35,000 to €25,000 per megawatt down to a range of €14,000 to €12,000, according to the scope of work,” he noted. “This decrease in O&M prices was natural and right for a sector evolving towards maturity, economies of scale and greater expertise, but it was also the result of pressure from investors that had to face hard times, especially in Italy."

He continued: "This second price-oriented approach not only brought prices down but also led to a decrease in ordinary as well as preventive service quality. My message to investors is that precisely because they have reached the lowest possible O&M prices, in many cases under real cost levels, their savings can be partially used to increase quality for their plants."

Thus, said Torri: "For few thousand euros more per megawatt a year, they can take a different approach and preserve value by having the plant performing at its best for its whole lifetime.”

Stern Energy will be presenting its predictive maintenance offering alongside Suncycle at the upcoming Solar Asset Management Europe conference in Milan, Italy, on November 9 and 10. The companies are joint Diamond Sponsors of the event.

Their service offering will include Suncycle analyses of panel quality to reveal early signs of problems such as solar cell potential induced degradation or PID, which can lead to power losses of up to 50% and may be difficult to spot at very early stages within traditional operations and maintenance schedules. At the same time, Stern Energy will be able to provide expert maintenance services for solar inverters.

“We hire most of our technicians from inverter manufacturers so we can provide deep service capabilities on inverters when their warranties expire,” said Torri.

Stern Energy manages a portfolio of 140 MW of solar power spread across more than 60 sites in the Italian market.

Does wind provide a guide to future O&M cost reductions?

Stern Energy's move into preventive maintenance emulates a trend that has already led to significant savings in the wind industry. A 2013 study by the US Department of Energy Sandia National Laboratories, for example, showed the use of preventive O&M schedules could cut the annual cost of corrective measures from between USD$17 and $18 per horsepower to between $11 and $13.

Whether similar savings could be achieved in the solar industry is open to question, since PV arrays have far fewer moving parts than wind turbines and are therefore less susceptible to failure. Nevertheless, Stern's experience shows it may often be more cost effective to prevent faults rather than deal with them after the event.

And if preventive maintenance takes off in solar, the wind industry may provide a clue about where a further level of cost benefit could come from. Wind asset owners are now embracing Computer Maintenance Management Systems for predictive maintenance, which allows them to forecast in advance where faults are likely to occur. The concept is said to cut costs by 47% compared to reactive maintenance.

Meet Stern Energy and Suncycle at Solar Asset Management Europe, on November 9 and 10 in Milan, Italy. Register now for your early bird discount.