Anatomy of Power Loss: Where Solar Performance Is Slipping

As global solar capacity races past two terawatts, the industry’s next major test is shifting from rapid deployment to sustained performance. New insights from the Global Solar Report 2025 by Raptor Maps, based on analysis of 193 GWdc of solar assets, reveal that underperformance is becoming a growing financial and operational challenge for asset owners worldwide.

In 2024, the average solar site experienced 5.77% power loss, translating to roughly $5,720 per MWdc in annual lost revenue. That figure represents a 15% increase from 2023 and more than a threefold rise over the past five years, signaling that performance erosion is no longer a minor inefficiency but a material risk to project returns. At industry scale, this underperformance equates to billions of dollars in unrealized revenue.

The data confirms that large system-level equipment failures remain the dominant drivers of power loss. Inverter faults alone account for about 37% of total observed losses, while string and combiner issues rose significantly year-over-year. Tracker malfunctions continue to contribute meaningful losses, particularly in regions exposed to extreme weather. Because these failures affect entire plant segments, they represent some of the highest-impact opportunities for corrective maintenance and revenue recovery.

At the same time, module-level damage is emerging as the fastest-growing category of risk. The report finds that module-related power loss doubled between 2023 and 2024, driven largely by physical damage, cracked modules, diode failures, and offline panels. While these defects typically produce smaller short-term losses than system-level faults, they carry long-term degradation, safety, and fire risks, making them increasingly important from both reliability and asset-protection perspectives.

Climate-driven events are accelerating this trend. Solar markets exposed to storms and hail are reporting significantly higher rates of module damage per megawatt, reinforcing that extreme weather is becoming a structural factor in solar operations rather than an occasional disruption. The report also highlights variation by module technology, with thin-film systems exhibiting fewer module-level defects than crystalline alternatives, though physical damage remains a leading cause across all technologies.

Perhaps the most actionable takeaway lies in fault prioritization. Only about one-third of detected issues are classified as high priority, yet these defects account for roughly 90% of total observed revenue loss. As portfolios expand and labor constraints intensify, leading operators are increasingly turning to data-driven triage, aerial inspections, automation, and performance analytics to focus resources on the most financially impactful interventions.

Ultimately, the anatomy of power loss underscores a broader industry shift: solar competitiveness will increasingly depend not just on how much capacity is built, but on how effectively existing assets are monitored, maintained, and optimized over time.