Hoymiles launches first UL 3700 balcony microinverter
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- Hoymiles launched the HiFlow Pro, the first US microinverter certified under UL 3700, North America's new safety standard for plug-in balcony solar.
- UL 3700, officially published in December 2025, creates a dedicated certification pathway for plug-in PV systems that existing rules — written for much larger rooftop arrays — had failed to address.
- Eight states had signed plug-in solar legislation into law as of July 2026 — Utah, Maine, Virginia, Maryland, Colorado, Connecticut, Vermont, and New Hampshire — with nearly 30 states in total having introduced such bills.
- New York's legislature passed a balcony solar bill, but it was still awaiting the governor's signature as of July 16.
- Balcony solar is already hugely popular in Europe, particularly in Germany, and the US is now building the regulatory and safety framework to support the same technology domestically.
- The HiFlow Pro delivers 99.8% static MPPT efficiency, weighs 4 lbs (1.8 kg), operates from -40°F to 149°F, and one 360W unit produces up to 721.08 kWh annually; up to four units can run in parallel for 1,200W total output.
Why it matters: For renters and apartment dwellers who can't install rooftop panels, the HiFlow Pro is the first hardware certified under a national safety standard specifically for plug-in solar. With eight states already on the books and nearly 30 considering legislation, that certification removes a key regulatory hurdle for utility-compliant adoption.
