PUC warns committee to clarify whether S.202’s 1,200‑watt cap refers to panels or inverters

Representative Scott Campbell, vice chair of the House Energy and Digital Infrastructure Committee, opened a March 18 hearing on S.202, a Senate bill that would define and allow portable solar electric generation devices for customers.

Jake Marin, an attorney for the Vermont Public Utility Commission, told the committee the PUC “doesn’t have any significant concerns with the bill as it's been drafted,” but he flagged a key ambiguity: the bill's 1,200‑watt limit could be read as applying to a solar panel's DC rating or to the inverter's AC nameplate rating. "As I read this statute ... the maximum capacity meaning the capacity of the inverters can be not more than 1,200 watts," Marin said, and he urged the committee to confirm the intended meaning with technical witnesses.

Why it matters: legal and technical definitions determine whether some devices remain within PUC oversight and how the energy they produce is measured for billing and safety. Marin explained that under Vermont law, a facility’s capacity is typically defined by the inverter (the device that converts DC produced by panels to AC used on the grid), while product listings and vendor literature often quote panel or DC ratings, which can be larger. That mismatch can affect whether a device is treated as a regulated generation facility and how utilities account for its output.

Committee members pressed several practical points. One asked whether the PUC regulates consumer protections for panel sales and installers; Marin said the PUC’s consumer‑protection jurisdiction covers utility service and billing up to the meter but generally does not extend to the sale of panels or the business practices of installers — matters he said would fall to the Attorney General’s Office. He added that the PUC's jurisdiction “ends at that meter,” and issues inside a building such as wiring, fire safety or egress are governed by building and fire codes enforced by other agencies.

Lawmakers also asked whether utilities had been consulted. Marin said the commission had not undertaken a formal investigation but had informal conversations and recommended the committee hear from distribution utilities about how to account for any energy from portable devices so customers’ bills remain accurate. Committee members indicated they would support utility requests for notification of on‑site generation for safety reasons, particularly during outages when nonutility generation can be on the line.

Members queried smart‑meter deployment and Marin said smart meters are widely adopted in the state though some customers have opted out; he recommended utilities provide precise deployment information. The committee and Marin discussed that rooftop systems requiring Section 248 review normally receive a Certificate of Public Good (CPG) and that where a system ties into the customer's wiring (before or after the meter and main panel) can change oversight and interconnection practices.

Marin also noted that standards such as UL 3700 are not always explicit about whether they use panel or inverter ratings, reinforcing the need to ask technical standards organizations or UL representatives for clarification.

What’s next: committee members said they will call technical witnesses and representatives from the utilities later in the hearing to resolve the capacity definition and related safety, metering and notification questions. The committee paused for a short break to await one late member.

The hearing produced no formal votes or motions on S.202 during the session described.