People are continually motivated to improve the safety of PV connector systems. There’s more than one way to meet that goal, however. Here’s a closer look at the possibilities.
The U.S. Department of Energy says fires associated with solar panels or their components are uncommon. However, one of the reasons PV system design must always focus on risk mitigation is that blazes can occur and put people at risk. There are also special considerations for firefighters. Switch Disconnector
One Department of Energy program has provided resources to 10,000 firefighting professionals to keep them safe while dealing with solar panel fires. Rapid shutdown connectors are also vital because they allow firefighters to quickly disable the power to a panel in an emergency.
Amazon recently experienced several solar panel fires at its facilities. The e-commerce giant had at least six solar power-related arc events or explosions between April 2020 and June 2021.
A third-party auditing company hired to investigate the events discovered 259 major problems and a critical one. Connectors were partially to blame, too. Some of the issues included improper connector installations and mismatched module-to-module connectors.
This is a sobering reminder that PV system design and associated safety improvements are not guaranteed solutions. Errors, carelessness and insufficient training can make solar panels less safe.
Many business decision-makers are open to solar panels. They appreciate the money-saving opportunities and sustainability benefits. However, the fires and explosions at Amazon caused the company to temporarily disconnect its installations and reinspect them for safety’s sake. That was the right move, but these challenges could discourage leaders from ramping up their solar energy usage as fast as they otherwise might have.
Estimates show a 22% increase in solar panel power in 2021 compared to 2020. Moreover, this option is the third-most installed renewable energy type, behind hydropower and wind. Those are encouraging trends, but safer system designs are essential for retaining interest in panels at the commercial or residential level.
Regulations already require connectors to have rapid-shutdown features in case of electrical-arc emergencies. However, it’s always good to minimize the risk of problems even further by using technological advancements. One recent example comes from Marley, a company that created a connector enclosure called the ArcBox.
Lab testing is a critical part of developing new products. For example, vibration tests verify items have a suitable build for their environment. Similar tests are necessary for PV equipment since it’s constantly exposed to the elements. A university and a fire-testing laboratory independently verified the ArcBox. Customers can install it as part of Marley’s full-roof system.
The ArcBox has a patented, hinged design surrounding the DC connector inside a highly temperature-resistant refractory lining typically used in foundries. Manufacturers have recently started making the material in more complex shapes so they’re suitable for PV applications. The connector is suspended between cable-sealing grommets. The design also uses ventilation and drainage ports to keep it within its specified operating temperature range for the rated current and ensure the area around it remains dry.
Daniel Redfern, marketing manager at Marley, explained the safety benefits. “[The ArcBox] provides further peace of mind for specifiers and end users against the risk of electrical arcing, which can result in extremely high temperatures — beyond the melting points of many metals used in these applications — and benefits from our 15-year guarantee when installed as part of our total roof system. With the ArcBox, any arc is safely contained and cannot spread to combustible materials within or near to the solar installation,” he said.
Shutting off the power quickly when needed is essential. However, the goal is to explore how to reduce the likelihood of emergencies that could necessitate using shutdown connectors.
Some companies are investigating new materials for connectors. For example, chemical company SABIC developed a copolymer resin representatives believe is an excellent candidate for emerging solar panels. This resin can tolerate 1,500 system volts without disintegrating.
Such progress will help consumers feel more confident about installing solar panels and embracing this renewable energy option. Research and development efforts are showing new ways to make PV connectors safer, and these advancements will make solar technology safer for everyone involved.
Elsewhere, people are considering Internet of Things monitoring systems for solar panels. They can provide alerts about malfunctions, energy production and more. Although these don’t solely relate to connector safety, they supplement it by giving users better oversight.
Metal Cable Ties As people progressively learn more about solar panels and their associated risks, they can — and should — apply that knowledge when making safer designs. Rapid shutdown connectors are excellent examples of such improvements, but the enhancements cannot end there. Even though fires are rare, they’re still dangerous and could put lives and properties at risk.