Plug-in solar energy, also known as balcony solar energy, is a popular choice in Europe and is now starting to be introduced in the United States. Last year, Utah introduced legislation, becoming the first state to allow the use of a 1.2 kW plug-in solar panel system without utility approval. Now, the largest solar energy state in the country has shown interest in plug-in solar energy.

Earlier this week, Senate Bill 868, drafted by Democratic Senator Scott Wiener of San Francisco, was introduced to the California Senate. The Access the Sun Act would eliminate red tape and establish statewide safety standards for portable solar systems, which are commonly found on balconies throughout Europe. Reducing permitting and interconnection barriers would enable households to generate their own clean electricity and reduce electricity costs through plug-and-play solar technology.

According to the Environmental Working Group, balcony solar systems can be installed on railings or tilted in the backyard, and plugged directly into a standard 120V outlet using an integrated micro-inverter. Some plug-in systems also include batteries. The solar systems are small, typically no more than 1.2 kW, and cost little more than $1,000.

UL Solutions has noticed this and has launched a new testing program for plug-in solar systems. The program is based on the evaluation of UL 3700 (Outline Investigation for Interactive Plug-in Photovoltaic Devices). It defines the construction, performance, and labeling standards for plug-in solar systems, providing a reliable foundation for manufacturers to design products that consistently meet safety and performance requirements.

Ken Boyce, Chief Engineering Vice President of UL Solutions' Industrial Testing, Inspection, and Certification Division, stated, "Our new certification program for plug-in solar systems provides clear information for manufacturers and consumers, allowing them to confidently adopt plug-in solar systems. "By defining how to construct these systems, evaluate safety, and ensure safe installation, UL 3700 helps reduce potential risks and opens the way for more people to access resilient solar energy. ”

Solar energy systems connected to household circuits pose certain risks, such as system overload and the potential for electricity to flow back into the lines. In addition to defining safety standards for manufacturers, UL 3700 addresses these additional risks by requiring features that reduce the risk of accidental contact with hazardous electrical components, promote safe installation, prevent overload, and prevent current from flowing in the wrong direction. Plug-in solar energy systems certified by UL 3700 are suitable for tenants and homeowners who cannot install rooftop systems and can be used to provide backup power for critical equipment during power outages.