Celebrating Ten Years of PVEL’s Testing at PVUSA

By Jenya Meydbray

March 30th, 2021

In 1986, a PV module cost about 9.40 USD/watt. President Reagan dismantled the solar array on the White House. Solar PV technology was unproven commercially and its outlook was uncertain, to say the least. But in Davis, California, a dedicated team of scientists was beginning to a develop a research site that helped transform solar PV into a scalable technology. The 86-acre, purpose-built testbed was named the Photovoltaics for Utility-Scale Applications research site, or PVUSA.

By the time PV Evolution Labs (PVEL) started testing at PVUSA in 2011, the cost of a PV module had dropped to just 1.39 USD/watt and more than 30 GW of solar was installed worldwide. Over the past decade, the expansion of solar power has continued to skyrocket. Clearly, many different factors have contributed to this growth, but the work conducted at PVUSA played an important part.

“When I was the project manager of PVUSA in the early days there was much speculation but little information about solar panel operation and performance in real-world applications.

The work there was pivotal in gaining a greater understanding of the life and cost challenges that PV faced and helped to focus manufacturing and quality control improvements in the industry.”

Tammie Candelario, former PVUSA project manager
Photo courtesy Tammie Candelario

PVUSA was developed by the utility company PG&E as a public-private partnership to study the impact of high-penetration solar on the electric grid. At the time of construction, it was one of the only grid-connected solar projects in the world. Many utilities were skeptical of solar energy products. There was no consensus on the relative merits of different photovoltaic technologies, installation methods or O&M techniques. However, over time other organizations saw untapped potential in solar energy and lent their support to the project, including the U.S. Department of Energy (DOE) and California Energy Commission. *

According to a PV-USA report from 1993, the project was “designed to narrow the gap between a large utility industry that is unfamiliar with PV, and a small PV industry that is aware of a potentially large utility market but unfamiliar with how to meet its requirements. The objectives are:

  • To evaluate the performance, reliability and cost of promising PV modules and balance-of-system (BOS) components side-by-side at a single location
  • To assess PV system operation and maintenance (O&M) in a utility setting
  • To provide U.S. utilities with hands-on experience in designing, procuring, and operating PV systems”

Then and now at PVUSA

PVUSA in 1990 (left, courtesy Tammie Candelario) and today (right, courtesy Victor Samuel of PVEL).

Then and now at PVUSA

PVUSA in 1990 (top, courtesy Tammie Candelario) and today (bottom, courtesy Victor Samuel of PVEL).

The original PVUSA projects proved so influential that their legacy can be seen in the technical specifications of PV modules: the “P” in PTC rating refers to PVUSA test conditions. PTC ratings are intended to be a more realistic measure of PV module output in central California than ratings at STC, or standard test conditions. As a report issued in 1990 notes, “PVUSA’s suppliers have tended to be optimistic with regard to project array efficiency.” Since then, energy predictions have continued to evolve and today PVEL’s PAN files and IAM profiles are regularly required to develop bankable energy assessments.

“I had the great opportunity to work with PVUSA from 1988 – 1993 which at the time was the world’s leading outdoor PV laboratory. PVUSA empirically tested emerging PV technologies and applications such as bifacial, thin-film, concentrators, inverters, and horizonal single axis trackers.

Nextracker is proud to be part of some current activities at PVUSA including bifacial testing and is thrilled PVEL has continued its valuable contributions advancing photovoltaic system understanding through world-class measurement and verification of key performance attributes.”

Dan Shugar, Founder and CEO, Nextracker
Photo courtesy Nextracker

For the past ten years, PVUSA has been the home of PVEL’s outdoor testing for a broad array of products – everything from mounting systems to PV module coatings and rapid shutdown devices.

Learn More About PVEL's Field Testing

Research through the years

“In 1997 Chuck Whitaker (Endecon) and I (Sandia Labs) teamed up to evaluate the performance and reliability of a variety of aged PV array technologies at PVUSA, in cooperation with the associated module manufacturers. This unique facility played a crucial role in the demonstration and evolution of grid-tied PV systems and BOS components.”

David King, Distinguished Member of Technical Staff, Sandia National Laboratories

PV module failures observed in the field at PVUSA during the 1990s (left, courtesy David King) and in late 2020 as observed by PVEL (right) show that field testing new products remains critical today.

PV module failures observed in the field at PVUSA during the 1990s (top, courtesy David King) and in late 2020 as observed by PVEL (bottom) show that field testing new products remains critical today.

Research at PVUSA helped utilities understand the impact of solar power on the grid and led to the development of net energy metering. It also served as a proving ground for solar PV technology. According to Matt Cheney, who personally owned the site from 2003 to 2016 and played a key role in ensuring the survival of the facility in the aftermath of California’s 2005 energy crisis, the research at PVUSA involved most, if not all, early PV products. He is pictured below with solar concentrators that were tested at PVUSA in the 2000s, but ultimately did not succeed in the market.

I have no doubt that we would not be where we are today without PVUSA’s trove of performance and operational data showing that solar photovoltaic technologies work seamlessly and predictably, making PV project financing very compelling.

Matt Cheney, Managing Partner and Founder of CleanPath Emerging Markets; CEO of Catalyst Energy Partners
Photo courtesy Matt Cheney

Solar products and solar project development have certainly come a long way since the early days of PVUSA. Yet building investor and asset owner confidence in the benefits of a new technology still requires the right combination of data from both the lab and the field. Solar products operate under the sun in the real world, a microcosm of which was created at PVUSA by solar industry pioneers and leaders.

We’re honored to continue the legacy of PVUSA with our testing today.

Learn more about our testing at PVUSA

We offer a broad range of studies for evaluating comparative energy yield, product safety, runtimes and more.

Download our PVUSA Brochure

*PVEL recognizes the following utilities and public agencies that provided support to PVUSA in its early years:

  1. Department of Energy (DOE)
    • Jet Propulsion Laboratory (JPL)
    • National Renewable Energy Laboratory (NREL)
    • Sandia National Laboratories (SNL)
  2. U.S. Department of Defense (DOD) Tri-Service PV Review Panel
  3. Electric Power Research Institute (EPRI)
  4. California Energy Commission (CEC)
  5. Pacific Gas and Electric (PG&E)
  6. Maui Electric/State of Hawaii
  7. City of Austin
  8. Texas New York Power Authority (NYPA)
  9. New York State Energy and Research Development Authority (NYSERDA)
  10. Sacramento Municipal Utility District (SMUD)
  11. Central and South West Services, Incorporated (CSW)
  12. Public Service Company of Colorado (PSCo)