Large-scale O&M standards are changing. What once was an afterthought handled by third-party technicians is now an in-house business line for huge solar contractors like SOLV Energy and Primoris Renewable Energy. As the scope of solar projects has grown, so has the need for technicians whose whole focus is preventive and corrective maintenance of solar arrays.
“I think it took from 2008 through 2016 that we, as an EPC, put a gigawatt in the ground,” said Reegan Moen, VP of business development for services at SOLV Energy, a utility-scale solar EPC with an O&M program. Now, SOLV is maintaining individual arrays pushing 700 MW and pursuing contracts for projects larger than 1 GW.
Without this tailored oversight from O&M techs, a project in the range of hundreds of megawatts can underperform and result in massive financial consequences for stakeholders.
“It’s not like it was 10 years ago. If you miss [daily performance goals] by a few pennies, maybe it was a few thousand dollars,” Moen said. “Nowadays, the projects are so big, you miss it by a few pennies, and it’s hundreds of thousands of dollars, and it can affect your internal bottom line.”
Keeping the plant on
A solar O&M technician with Primoris Renewable Energy checks wire management on a solar tracker project. Primoris Renewable Energy
As the size of solar projects has increased, the methods of maintaining them have evolved, especially as new O&M standards and technologies enter the scene.
With each project having different demands, there is no rigid metric for how many technicians to place on a solar array. Billy Watts, VP of O&M services with Primoris Renewable Energy, a large-scale solar EPC, said the company generally employs four technicians at a 250-MW solar project.
“We try to have people at the site at all times,” Watts said. “Just in case … something’s down, it doesn’t take two or three days to get someone there.”
O&M technicians do not need to be electricians, although having some electrical knowledge is helpful. Primoris works with technical high school and college programs to build O&M technician curricula and expand the hiring pool for this career. The company also prioritizes hiring military veterans.
SOLV, meanwhile, aims to hire technicians directly from the local contractors that construct its projects, keeping jobs within communities.
O&M technician training covers safety practices necessary for working within a live electrical plant. Technicians become certified to handle, repair and replace specific components from original equipment manufacturers to preserve warranties and keep the array running.
Their work is a combination of preventive and corrective maintenance. Daily tasks are delegated from monitoring and data sets pulled from their respective arrays. These sources can pinpoint certain components that are underperforming or malfunctioning.
A typical day for a technician would first begin with checking system monitoring to ensure all inverters are functioning. If a particular area isn’t producing as expected, technicians will check panels, combiner boxes or wires for issues. Regular maintenance would then be performed, such as greasing solar tracker drives, tightening bolts and visually inspecting components.
Regular array upkeep
SOLV Energy O&M technicians wearing arc flash-resistant equipment check a combiner box. Maintaining solar projects at this scale poses some safety risks. SOLV Energy
Inverters require the most attention, because their failure can heavily impede a solar array’s production. Fans and filters can become clogged with debris, especially in dusty environments. Substations similarly have filters and HVAC systems that require regular checks. Fuses inside combiner boxes can overheat and blow, as well. If not properly lubricated, tracker drives can seize and stop moving, cutting a panel row’s production.
Each element of the array has different methods for upkeep, but if something breaks, Moen said it’s best practice to keep a stock of replacement components as backup. Long lead times for replacement components can be the difference between a profitable or non-profitable array.
Besides solar technology, site maintenance also includes the land itself. Many solar trackers have integrated articulating posts that work on steeper inclines and reduce the need for grading land, but some land may need to be disturbed to build access roads and establish water retention measures. This means technicians are responsible for ensuring stormwater outlets are unobstructed to avoid runoff that could wash away access roads.
Landscaping and agricultural abatement requires regular attention either with mowing equipment or livestock such as sheep. Project owners are increasingly concerned with reducing long-term grounds maintenance costs.
“Previously, it was all about CapEx — get the project built — but there was no consideration, really, of what does OpEx mean, and how much does it cost to mow a site five times? That’s going to eat into your budget,” Moen said.
Tools of the maintenance trade
Solar O&M technicians aren’t simply equipped with hand tools and electrical meters to tackle maintenance on these large project sites. They’re in constant contact with remote operating centers (ROC) that help them address areas of underperformance and act as an additional layer of safety, especially on more remote sites.
O&M technicians are responsible for upkeep of all technologies on a solar array — including storage, power electronics and the solar panels themselves. SOLV Energy
Sending a person out into an active power plant of this scale poses risks, so using technologies like drones reduces the inherent danger and amount of labor necessary to complete this work. Technicians can fly drones along fence lines to ensure they’re intact. Drones can also inspect for hotspots and use on-board GPS to mark where replacements are needed.
“The days of being a technician and just going out there and doing it and no paperwork — those days are gone,” Watts said. “You need a technician that’s not only technically sound but also has the ability to type and work in computerized systems.”
While performing maintenance on electrical components, technicians wear full-body arc flash suits. They always work at least in pairs as a safety precaution. “Safety seconds” watch over the person performing the maintenance, remaining in frequent contact with the ROC. On more remote solar sites, SOLV gives technicians satellite phones and has contracted with helicopter services in case anyone needs evacuated.
“These bigger projects nowadays are not cookie-cutter squares, nice ground, previously a cornfield,” Moen said. “These are found by developers, and they happen to be close to an interconnection or a [transmission] line, and they could be hours away from population.”
One branch helping the other
Large-scale solar project maintenance remains in a state of flux, because arrays will continue to be built at larger capacities and in places further from population centers. O&M service runners are trying to make projects pencil while dealing with details like meeting prevailing wage requirements county-by-county, stockpiling enough equipment to make immediate replacements and ensuring technicians are trained to work safely in sometimes perilous conditions.
Watts said that while Primoris both builds and maintains solar projects, the two services are connected. The company takes lessons from each side to improve how the other works.
“The main thing is getting that [O&M] information and turning it back in so that we can build a better site,”
he said
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