Balcony Solar in Maine
Maine is the first US state to name UL 3700 in its statute. LD 1730 lets you self-install up to 420 W AC of plug-in solar; 420–1,200 W requires a licensed electrician, a dedicated circuit, and 30-day utility notice.
Reviewed August 6, 2026 against primary sources. Laws change — the sources below let you re-check.
Does Maine require UL 3700?
Yes — the statute names UL 3700.
(1) Listed or certified in accordance with UL 3700, the Outline of Investigation for Interactive Plug-in Photovoltaic Equipment and Systems … by UL LLC …; (2) … a standard comparable to UL 3700 from a nationally recognized testing laboratory; or (3) Configured in accordance with the National Electrical Code …
The first US law to name UL 3700 — but it offers three alternative routes: UL 3700, a comparable NRTL standard, or NEC configuration. It names the standard without making it the only path.
Why this matters: “certified by UL” names an organization; “certified to UL 3700” names a plug-in-PV standard. They are not the same claim. Full explainer →
What the law does
- Inverters must shut off within 0.2 seconds if grid power is disrupted (anti-islanding).
- No interconnection application, agreement, or study required.
- Not eligible for net energy billing — excess export is uncompensated.
What's still unsettled
- The UL 3700 requirement has two alternatives (a comparable NRTL standard, or NEC configuration), so it isn't a hard UL 3700 mandate.
- Systems of 420–1,200 W lose the DIY premise: they require a licensed electrician.
Before you buy in Maine
A state law opening the door is only one of three gates. The gear must actually be certified to what the law asks for — and today no plug-in kit sold in the US carries UL 3700 yet. Your utility may still want notification. If you rent, your lease or HOA is a separate yes. What "UL 3700 certified" really means →