‘A troubling reality’: Study claims swathes of US solar projects underperforming

Facebook
Twitter
LinkedIn
Reddit
Email
Image: SEIA/Twitter.

A new study suggests the US solar industry has “turned a blind eye” to the realities of asset performance, with facilities found to be underperforming compared to their production forecasts.

In collaboration with ten of 15 largest US solar asset owners, risk management company kWh Analytics analysed more than 30% of the industry’s utility-scale and commercial and industrial solar projects and found a quarter missed their production targets by over 10%, even after adjusting for weather.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

While the sector uses the same software tools and engineering firms to generate production estimates, a lack of accepted standards means that forecasts can vary depending on who is running the model, the report says.

According to kWh Analytics, when solar was still an untested asset class in the early 2000s, initial estimates were conservative and projects typically outperformed expectations. However, with the pace of market development, new technologies, more complicated site designs and a more competitive landscape, production estimation became more complex, leading to forecasting becoming overly optimistic.

“Fundamentally, it is our hope that this report serves as a platform to discuss the data-driven approaches to inform deployment of capital,” kWh Analytics said in a statement accompanying the study.

The firm quantified the magnitude of the industry’s inaccuracy when relying on P50 estimates, a statistical measure that indicates the base case, predicted energy yield.

The analysis of more than 30% of the industry’s non-residential projects in the US compared actual production against original P50 estimates for operating years between 2016 and 2019 and found that projects on average underperformed by 6.3%. The results do not incorporate system losses due to utility curtailment.

kWh says the performance results against P50 estimates highlight “a troubling reality”: that the industry is “relying on inaccurate and unreliable production estimates”.

Efforts are said to be underway to correct the issue, with solar asset owners collaborating to quantify potential biases and using data to drive accuracy and transparency in future financings.

“While developers may be concerned about the near-term impact on solar asset valuations resulting from adjusted P50 estimates, we believe that this course correction will enable our industry to continue the structural trend of lower-cost capital entering into the industry,” kWh Analytics said in the report. “This ultimately has a positive impact on solar asset valuations.”

13 October 2026
San Francisco Bay Area, USA
PV Tech has been running an annual PV CellTech Conference since 2016. PV CellTech USA, on 13-14 October 2026 is our fourth PV CellTech conference dedicated to solar manufacturing in the USA. From polysilicon, wafers, ingots, cells and modules, to critical component suppliers including glass and frames, the event connects every stage of the value chain under one roof. PV CellTech USA also brings together investors, innovators, manufacturers and industry stakeholders to collaborate and strengthen domestic solar manufacturing across the United States.

Read Next

June 18, 2026
Renewable energy investment platform Chrysalis Renewables LP (Chrysalis) has acquired the Atlas V and Atlas VI solar projects in the US.
June 18, 2026
The Arizona Court of Appeals has vacated a decision that Arizona utilities can impose additional charges on residential solar customers.
June 17, 2026
Distributed solar developers including MCEC, Aligned Climate Capital and Catalyst Power have secured funding across US projects.
June 17, 2026
Independent power producer (IPP) Alluvial Power has reached commercial operation at its 150MWac project in Ford County, Kansas.
June 16, 2026
European inverter manufacturing capacity has now surpassed 100GW, according to figures from PV Tech Market Research.
Premium
June 16, 2026
PV Tech Premium sat down with Anne Loomis, partner at Troutman Pepper Locke, to discuss the safe harbour deadline for US solar developers.

Upcoming Events

Media Partners, Solar Media Events
June 30, 2026
Sacramento, California
Media Partners, Solar Media Events
August 25, 2026
São Paulo, Brazil
Media Partners, Solar Media Events
September 1, 2026
Mexico City, Mexico
Solar Media Events
September 9, 2026
Schaumburg, Illinois
Media Partners, Solar Media Events
September 9, 2026