Our Origins

October 21, 1991: Letter from Bob Hammond to Dr. Chuck Backus: "...Wouldn't you like to have an internationally recognized PV module qualification facility located at Arizona State University?"

November 25, 1991: Dr. Backus, Dr. Wood, and Mr. Bob Hammond met at Denny's (fast food restaurant) in Tempe, Arizona; and agreed to establish a "Photovoltaic Testing Laboratory" (PTL) at Arizona State University (ASU) with a start date of January 1, 1992. The objectives were defined as followed:

  • Develop a hands-on training laboratory for graduate and undergraduate students.
  • Provide state-of-the-art laboratory equipment with which faculty, staff, and students could perform research related to Photovoltaic (PV) module reliability, durability, and performance.
  • Establish the capability to perform qualification testing per all relevant national and international standards.
  • Provide PV module qualification testing services to the PV industry.
  • Provide related applied research to the PV industry.


Arizona State University's PTL (ASU-PTL) Evolution

Two events occurred in 1992 that established the beginning of the PTL in terms of hardware: First, development of a  hail impact tester. This placed Arizona State University in the unique position of being the only non-government laboratory in the world with a PV module hail impact tester. Secondly, Sandia National Labs provided Arizona State University with a surplus environmental chamber. This chamber, originally used by the Jet Propulsion Laboratory (JPL) for PV module environmental tests, was shipped to Arizona State University in mid 1992 and installed at Arizona State University.

From October 1993 to December 1995, the PTL worked under contract to the National Renewable Energy Laboratory (funded by the U.S. Department of Energy, DOE) to develop the criteria for PV module certification and laboratory accreditation. The "Photovoltaic Module Certification / Laboratory Accreditation Criteria Development: Implementation Handbook" (figure 2) was published in 1996.

As the PTL continued to evolve, a variety of related contract work was performed. This work included PV module characterization, hot spot endurance testing and hail impact testing. In 1994, another essential piece of testing equipment was developed, a dynamic load tester.

By June of 1995, the PTL was fully equipped to perform the full Institute of Electrical and Electronics Engineers (IEEE) 1262 and much of the Underwriters Laboratories (UL) 1703 qualification test series. At this time, a multi-client program was initiated to test per IEEE 1262, IEEE Recommended Practice for Qualification of Photovoltaic (PV) Modules for two manufacturers and UL 1703, Standard for Safety - Flat Plate Photovoltaic Modules and Panels for three module manufacturers. This test program established the Arizona State University- PTL as the only non-government laboratory in the United States with the capability to perform all of the tests required by IEEE 1262, International Electrotechnical Commission (IEC) 61215, JPL Block V, and UL 1703.

In July 1996, PTL moved to the new Arizona State University East (Arizona State University) campus in Mesa which provided the space required to fully develop an international testing laboratory. This campus was created from the acquisition of property from the Williams Air Force Base, located at 6001 South Power Road in Mesa, Arizona.

In December 1996, the PTL applied for accreditation to the American Association for Laboratory Accreditation (A2LA). A2LA was chosen for this task because it is one of two agencies within the U.S. recognized to accredit laboratories to the International Organization for Standardization (ISO) Guide 25, General Requirements for the Competence of Calibration and Testing Laboratories. This accreditation would also recognize Arizona State University-PTL's compliance with the relevant International Standards Organization (ISO) 9000 series of standards as well as PV-1, Criteria for a Model Quality System for Laboratories Engaged in Testing Photovoltaic Modules. The A2LA audit was completed on March 21, 1997. The audit resulted in a total of eleven deficiencies (the majority of which were the result of calibration laboratories that the PTL used) and these deficiencies were corrected by June 3, 1997. Accreditation was awarded on June 23, 1997 and made the PTL one of only three laboratories in the world that are officially recognized as testing laboratories in the field of photovoltaics.

In 2000, a third environmental chamber was installed. This chamber was designed specifically for "Thermal Shock" tests of PV modules. With three chambers online, all three environmental tests (temperature cycling, humidity-freeze, and damp heat) can be conducted in parallel, reducing the total qualification test time from 110 days to 90 days. In August 2001, Arizona State University-PTL was qualified by Underwriters Laboratories Inc. (UL) to participate in its Third Party Test Data Program. The program allows PTL to perform qualified safety testing on photovoltaic modules to the UL 1703 standard. The test results are then reported directly to UL after test performance. This helps the PV manufacturer by providing faster quotation response time from PTL, and full test witnessing by UL will no longer be required. The UL Qualification was successfully renewed every year.

Dr. Mani efforts extended to testing fuel cells, membranes, catalysts and MEA. By 2003, PTL technical capabilities and exclusivity included: First laboratory testing a residential fuel cell system in Arizona; First academic research laboratory to develop a unique UPS based on fuel cell capable of supporting a computer for up to 192 hours; First laboratory to develop a thermal test bed (TTB) for the outdoor testing and energy rating of PV modules; Only university laboratory in the united states to consistenly participate in the PV standards development activities

In 2008, the PV certification testing division of PTL was spun off as a commercial testing lab to meet the demands of the unprecedented growth of the PV industry which currently operates as TUV Rheinland PTL in Tempe. The fuel cell division was spun off into another academic lab at ASU. The PV research division was renamed ASU Photovoltaic Reliability Lab (ASU-PRL) in January 2009 and continued to operate in Mesa.


 Arizona State University Photovoltaic Reliability Lab (ASU-PRL)

The mission of ASU-PRL is to predict climate-specific and construction specific lifetime of PV modules based on actual field failure modes and mechanisms, accelerated lifetime testing (ALT), physics based models and statistical models. ASU-PRL has been funded by DOE, Science Foundation Arizona, Arizona Public Service (APS) and Salt River Project (SRP) and Electric Power Research Institute (EPRI). ASU-PRL has already performed field reliability evaluations of several thousand modules in diverse climates of Arizona, California, Colorado, Florida, Texas and New York, and is currently funded to study methods to reduce module operating temperature, long-term durability and reliability of . These field evaluations include: extensive visual inspection including snail trail observation, IR imaging, EL imaging and I-V measurements on several thousand statistically selected strings and modules. Since 2010, ASU-PRL has generated more than 50 graduate students with over 20 in the last three years alone. In the last three years, ASU-PRL has published more than 31 papers on PV reliability in peerreviewed conferences and journals. At 40th and 41st IEEE Photovoltaic Specialist Conferences (PVSC), ASU-PRL student Jaewon Oh won the Best Student Paper Award for Topical Area 12 on “Reliability of PV”.