Report on Joint DOE/SEMI PV Group Crystalline Silicon PV Cell Workshop
On May 13, 2009, SEMI PV Group, the US Department of Energy (DOE), the Solar America Board of Codes and Standards (ABCs), Arizona State University (ASU) and TUV Rheinland Photovoltaic Testing Lab (PTL) hosted a workshop on Crystalline Silicon Terrestrial Photovoltaic Cells at Arizona State University. The goal of this workshop was to assess the need for an industry-supported standard specification for c-Si Terrestrial PV cells, based on a report prepared by Dr. GovindaSamy TamizhMani of ASU’s Photovoltaic Reliability Laboratory. The report, Crystalline Silicon Terrestrial Photovoltaic Cells –Supply Chain Procurement Specification Guideline, also recommends additional supply-chain specification standards related to PV module manufacturing including encapsulant, backsheet, junction box, cables, glass superstrate, and framing materials.
The workshop drew attendees from over 40 organizations. The group first toured TUV Rheinland’s state of the art testing lab, which conducts tests (including hail resistance, heat endurance, cell performance, module impact, and safety) as specified by IEC 61215, 61730 and UL 1703. Most, if not all modules, are required to pass these tests before they can be sold in various parts of the world. The TUV tour was followed by a visit to the Arizona Public Service Solar Test and Research Center, one of the larger outdoor multi-product array test facilities. After touring these facilities, the the workshop continued at Arizona State University’s Polytechnic campus.
- Dr. TamizhMani presented the need for a PV cell procurement specification. Although a large number of module manufacturers acquire PV cells from their suppliers, there is no baseline requirement standard for PV cells. A large portion of module qualification failures are related to either a cell itself or a cell interconnect break. Quantitatively, 45% of module failures came from corrosion, and 41 % are from either the cell itself or interconnect break. As PV modules are typically guaranteed to last over 20 years by most manufacturers, it is critical to have the cell performs the way they were designed for the life of module.
- Kevin Nguyen of SEMI PV Groupgave a report on current Standards activities at SEMI PV Group, including individual updates on ongoing efforts in Europe, Japan, North America, and Taiwan. PV Group is currently engaged in developing a PV Standards Roadmap.
- Richard Bozicevich from TUV Rheinland delivered details of testing standards and how each module is tested as described in IEC and UL standards. Jack Castagna, also from TUV, presented how each component of the PV module is tested at TUV Rheinland.
- Marie Mapes of the DOE showed the landscape of the renewable energy department and how DOE is helping with PV technology roadmap.
- Christine DeJong of ASTM introduced the ASTM organization and its current standards activities in Committee E44 on Solar, Geothermal and Alternative Energy Sources, and also listed existing PV standards developed by all standards organizations.
- Win Baylies of Baytech reported on cell yield management.
- Kevin Lynn of Sentech presented ongoing research at Solar ABCs on topics including expedited permitting for PV systems and high wind loads and model codes for PV arrays at Solar ABCs.
These reports can be accessed at: http://teams.semi.org/stds_napv.
While some attendees remarked that convincing cell-makers to agree to a cell specification would be difficult, the general consensus was that a template for describing c-Si cell specifications is urgently needed. Both PV Cell and Module producers need a specification for c-Si cells that serves their mutual needs: defining appropriate cell details, values and tolerances for producing, purchasing and testing these products. To start work on a c-Si cell specification template, a SEMI PV Cell Specification Standards Working Group has been formed, and includes representatives from BP Solar, Schott Solar, Advent Solar, TUV Rheinland, and NREL. This template will reference Dr. TamizhMani’s work and the cell specification format recently introduced in Germany by several cell makers including Q-Cells and Ersol. Discussion of the first draft of the template will take place at the Working Group’s inaugural meeting on July 14th during InterSolar America 2009 in San Francisco, California. For more information, please contact Kevin Nguyen of SEMI PV Group, at firstname.lastname@example.org