Summary of collaborative photovoltaic industry work to proactively improve codes and standards for photovoltaic power system applications

Several important milestones in codes and standards pertaining to the design, installation and operation of photovoltaic (PV) power systems have recently been completed with collaboration of participants from all sectors of the PV industry, electric utilities and the US Department of Energy´s National Photovoltaic Program. Codes and standards that have been proposed, written or modified include changes and additions for the 1999 National Electrical Code(R) (NEC(R)), standards for fire and personnel safety, system testing, component qualification and utility interconnection. Project authorization requests with the Institute of Electrical and Electronic Engineers (IEEE) have resulted in standards for listing PV modules and balance-of-system components. Industry collaboration with Underwriter Laboratories, Inc. (UL), with the American Society for Testing and Materials (ASTM), and through critical input and review for international standards with the International Electrotechnical Commission (IEC) have resulted in domestic and international standards for PV. Work related to the codes and standards activities through the International Energy Agency (IEA) is also being supported by the PV industry and the US DOE. This paper concentrates on and summarizes the important new NEC proposals for PV systems and also describes and shows the bonds between the activities in either standards writing activities. The paper also provides an analysis of changes and resulting impacts of selected proposed NEC changes on PV designs, installations and performance