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: 2021-07-07