Northwest Power Planning Council, February, 2001 Photovoltaic Warranty Requirements Issue: The recommended 5-year warranty requirements for non- metered solar PV are too onerous and not in keeping with industry practice (Comments 30, 59(b), 70(f)). Need clarification of warranty requirements for systems with battery backup.

Northwest Power Planning Council, February, 2001 Observations (1): The proposed credit for PV systems is based on the estimated present value of system output for a period of 20 years. California’s Emerging Renewable Resources buydown program requires a full 5-year system warranty. Module warranties are complex, and relate to percent rated output. However, PV modules are typically warranted for 20 to 25 years on materials and workmanship. The module warranties typically do not cover labor. The standard warranty for Trace inverters (the predominant inverter used in PV installations) is 2 years parts and labor. However, Trace offers a 5-yr warranty complying with California requirements at a list price ranging from about $50 to $130/kW, depending on model.

Northwest Power Planning Council, February, 2001 Observations (2): The administrator of the California buydown program reports few problems with the warranty requirements. – Module warranties typically cover parts (but not labor) – Inverter extended warranties cover parts & labor. – Installers (including local electricians) warrant balance of system and labor not covered by vendors. Probably add to charges to cover risk. – Warranties not required on installation for owner-installed systems. Warranties were generally not being secured until CEC required copies of warranties to be submitted with buydown applications.

Northwest Power Planning Council, February, 2001 Observations (3) The SMUD PV Pioneer program warranty: – 20 to 25 year warranty on modules (by vendor). – 5-year warranty on inverters (by vendor) – 2-year warranty on balance of-system and installation, including leaks (by utility/installer). – No standard battery system, but will be offering one this fall. The manager of the SMUD PV Pioneer program unequivocally recommends the above as minimum warranty requirements – Inverter mfrs provide SMUD with 5-yr warranties at no extra cost with bulk purchase. – Convinced that extended warranty requirements have lead to substantial improvement in inverter reliability. – Very few problems with modules.

Northwest Power Planning Council, February, 2001 Warranty recommendations Modules - 20-year warranty at 80% specified power output Inverters - 5-year warranty – Consistent with established practice – Encourages properly installed and reliable equipment and systems – Reasonable given that public subsidy is based on 20 years of production Exempt batteries and other equipment specifically associated with battery back up from warranty requirements – Battery backup is owner option and not essential to energy production. – Subsidy is based on unshaped energy production. Installation (inc. equipment replacement & leakage) - 2-year. – Exempt owner-installed systems. Copy of warranty documents be provided to local utility as condition of payment.