Rocky Mountain Institute and Clinton Foundation launch guide for hurricane-resistant rooftop solar

Colorado — Rocky Mountain Institute (RMI) and the Clinton Foundation released a new report, Solar Under Storm II, focusing on best practices for installing climate-resistant rooftop solar in high-wind regions.

A sequel to Solar Under Storm, published in 2018, this latest report offers new and sought-after analysis of rooftop solar survivability from the Caribbean during extreme weather events and hurricane-force winds. The report is available at no cost to researchers, solar installers, policymakers, and the general public to help spread best practices for solar installations.

Chris Burgess, RMI’s project director for the Islands Energy Program, said “The first Solar Under Storm was one of RMI’s most popular reports in 2018. It provides a set of best practices for ground-mounted solar projects in high wind zones. The report was adopted into the Eastern Caribbean Building Code and is used to inform technical requirements for utility-scale projects across the Caribbean.”

Solar under Storm II is a follow-up, focused on the resilience of roof-mounted solar. The report was written in collaboration with the Clinton Foundation, FCX Solar and several solar professionals from Puerto Rico, the US Virgin Islands, the British Virgin Islands, the Bahamas, and Turks & Caicos Islands. According to Burgess, “Rooftop solar is a critical energy asset that is experiencing tremendous growth globally. Solar is the number one source of electricity for many island nations, so it is important to understand how to secure these assets from major storms.”

Sanya Detweiler, associate director of the Clinton Climate Initiative, said “Our work across the Caribbean is to support island governments and vulnerable communities as they transition from fossil fuels to clean, renewable energy sources. In light of more intense and frequent storms, the knowledge and lessons captured in this report help to ensure that solar energy can be installed—and stay in place—even following extreme weather events.”

The new Solar Under Storm Part II report shows that rooftop solar survival in the face of major hurricanes and cyclones is achievable and lists a number of technical considerations and recommendations for system specifications in future projects in hurricane-prone areas. These recommendations include:

– If top-down clamps are required, use clamps that hold modules individually or independently;
– Specify bolt hardware that is vibration-resistant and appropriate for the environment and workforce;
– Do not use self-tapping screws for structural connections.

The report also identifies areas of opportunity for multi-party collaboration to improve the entire value chain and life cycle of rooftop solar in the region. These collaboration recommendations include:

– Collaborate with installers to implement and continuously improve QA/QC and operation and maintenance (O&M) processes;
– Collaborate with racking suppliers to carry out full-scale and connection tests representative of ASCE 7 3-second (Category 5 hurricane) wind speeds;
– Collaborate with solar module suppliers and distributers to ensure local availability of high-load, robust-frame PV modules.

The new report has been designed as guide for both technical and non-technical audiences, with the goal of creating more informed solar professionals, regulators, government officials, utilities, and customers. Ensuring roof-mounted solar installations survive hurricane-force storms applies not only to the Caribbean but also in other regions which have growing distributed energy systems and face intense storms, such as the Southeastern United States, Southeast Asia, East Africa, and the Pacific Islands.