The solar energy industry has experienced remarkable growth in recent years, ushering in a new era of clean, renewable power. However, as the first wave of solar arrays nears end-of-life — in 2023 alone, over 67 gigawatts of solar capacity reached the 20-year mark worldwide — it’s becoming evident that aging and degrading components are leading to decreased efficiency, high maintenance costs, and performance issues.
For investors in solar projects, underperformance means lower returns. For utilities and grid operators sourcing power from solar projects, underperformance risks grid instability at times of peak demand. For the larger energy transition, meanwhile, underperforming solar projects thwart progress to phase out fossil fuels from our power mix.
Repowering can restore and even enhance the performance of existing solar projects by upgrading or replacing key components like modules, inverters, and trackers. By upgrading existing systems with advanced technology, stakeholders can extend a project’s operational lifespan, optimize returns on investment, and ensure grid resilience.
While the prospect of repowering existing solar installations holds great promise, barriers stand in the way of widespread adoption. These include operational disruptions, significant upfront costs, and technical challenges (as retrofitting existing infrastructure with new technologies can introduce compatibility issues).
But overcoming these is urgent. The opportunity to fully leverage the benefits of repowering is diminishing with each passing day. It’s like a favorite pair of sneakers — they’re just not as springy after a few years.
And here’s the kicker: delaying maintenance leads to a point where the cost-effectiveness of replacement outweighs that of repair. Thus, utilities and developers stand to benefit hugely from quick, increased investment in repowering projects. After all, who doesn’t love a good comeback story?
When to repower
Crafting a repowering strategy requires a comprehensive site assessment to identify areas for improvement and prioritize components with the most significant performance impact. Inverters, PV modules, trackers, and electrical infrastructure are common candidates for repowering, as they offer the potential for substantial gains in system efficiency while minimizing downtime.
Developments in solar module technology continue to level up system efficiency and power. New, high-powered solar modules often have efficiencies above 20%, compared to older models at 15-18%; many can better withstand environmental extremes.
For utility-scale solar arrays with thousands of modules, new, high-efficiency module technology can drastically increase production. From tandem solar cells with their multiple layers of solar materials to bifacial solar panels that produce energy from both their front and rear sides, module technology continues to advance what’s possible from utility-scale systems.
Several energy providers have recognized the advantages of repowering, and their strategies aren’t being limited to solar alone.
In 2023, NextEra Energy announced its plans to repower the majority of its wind portfolio in the coming years. And DEPCOM Power in Arizona repowered a 70-MW solar plant after inverter fire-damaged equipment, and even integrated energy storage during the process. Meanwhile, Cooperative Energy also successfully repowered a retired coal-fired power plant into a combined cycle gas turbine power plant.
In each of these cases, repowering proves significantly more cost-effective than the alternative, particularly when factoring in new incentives and federal programs.
Best practices
When the signs point towards declining performance and increased maintenance demands, it’s time to consider repowering your utility-scale PV system.
Integrating energy storage into utility-scale solar systems more widely is critical to overcoming grid instability and boosting grid flexibility. For systems that already include energy storage, new battery technology offers advantages like ramp control, peak load compensation, capacity firming, and improved blackout recovery. While lithium-ion batteries remain dominant, alternative grid-scale short and long-duration energy storage technologies are approaching full commercialization. Meanwhile, thermal energy storage, iron-air batteries, and nickel-hydrogen batteries present the industry with an opportunity to not just repower aging systems, but also to revitalize them.
Repowering solar energy systems also requires a skilled workforce trained to work effectively, efficiently, and safely in high-voltage environments and understand the latest developments in solar component technologies. It is estimated that about one million solar workers will be needed to scale, maintain, and operate the clean energy infrastructure required to meet 2030 solar energy targets.
As the lynchpin of the clean energy transition, many utility-scale solar and storage systems have the potential to provide value far beyond their initial specifications and lifespan. Repowering unlocks this massive potential, ensuring that solar systems meet the evolving demands of clean energy production — and serving as a strategic investment that maximizes their returns.
Repowering utility-scale solar systems is not only a solution to aging infrastructure, but also a catalyst for the continued growth and evolution of the solar energy industry.
Will White is a solar application specialist at the manufacturer Fluke. The opinions represented in this article are solely those of the author and do not reflect the views of Latitude Media or any of its staff.
