PV Resilience

To better understand why some PV systems failed after the 2017 hurricane season while others survived, GPG hired DOE national laboratories to conduct post-storm field inspections and create guidance to help agency managers identify the most common PV vulnerabilities during weather events. View full-size infographic. [PDF - 508 KB]

GPG Findings 047, May 2021, PV RESILIENCE: ADDRESSING WEATHER VULNERABILITIES. GSA INVESTMENT IN PV: How many solar installations does GSA have? 154 GSA Facilities have PV Arrays. 27MW Total System Capacity. PV IS RELIABLE IN AN ANALYSIS OF 100,000 PV SYSTEMS, 80% TO 90% PERFORMED WITHIN 10% OF PREDICTED PRODUCTION OR BETTER. IMPACT OF 2017 HURRICANE SEASON: What was the major vulnerability found across PV arrays in Region 2? BERKELEY LAB AND NATIONAL RENEWABLE ENERGY LABORATORY assessed the impact of the 2017 hurricane season on 5 PV arrays in the Caribbean. INADEQUATE FASTENERS FOUND ACROSS ALL SITES SMALL UP-FRONT INVESTMENT IN LOCKING HARDWARE, CLAMPS, AND THROUGH-BOLTING CAN HELP PROTECT PV ARRAYS. DEVELOPING GUIDANCE: BERKELEY LAB worked with the Federal Energy Management Program (FEMP) to identify additional weather vulnerability risks. RISK ASSESSMENT FOR SAFETY, PERFORMANCE AND FINANCIAL. 27 CORRECTIVE ACTIONS MANY ARE LOW COST. CONSULT QUALIFIED ENGINEERS TO INTEGRATE BEST PRACTICES. KEY VULNERABILTIES AND POTENTIAL SOLUTIONS. What are the key vulnerabilities that lab researchers identified? STRUCTURAL VULNERABILITIES Top down clamps loosening or bending To correct: Use throughbolting or top-down clamps with improved features. Inadequate structural attachments to building in roof arrays To correct: Add mechanical attachments to improve structural integrity. ELECTRICAL VULNERABILITIES Improper wire management To correct: Protect wires from weather and support every 12 inches with clamps, clips or ties. Inadequate electrical enclosures To correct: Use proper NEMA-rated enclosures for the site’s environmental conditions. SITE VULNERABILITIES Unobstructed wind forces To correct: Use a wind calming fence to reduce wind forces on the PV system. Loose debris and equipment To correct: Secure or remove loose equipment and debris from the area around the PV system. Structural vulnerabilities exhibit the greatest safety, performance and financial risks. Wind is the most damaging weather factor and also the most complex to understand and plan for. [PDF - 508 KB]


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Last Reviewed: 2022-09-15