The Maine Public Utilities Commission voted last week to exempt nonresidential solar customers with larger solar arrays from its controversial new gross metering rules. The PUC granted the request to Insource Renewables, a Pittsfield-based solar installer that argued the new regulations made it cost-prohibitive for their larger customers.

“Ultimately, today’s decision is an important step in protecting the interests of Maine ratepayers,” said Vaughan Woodruff of Insource Renewables in a statement. “Insource Renewables is appreciative of the Commission’s willingness to evaluate the actual costs that we reported and to recognize that gross metering is clearly not effective regulatory policy for certain classes of Maine solar customers.”

Earlier this year, the PUC gave final approval to net energy billing regulations that gradually reduce the compensation new solar customers receive for the energy they produce, including power that is generated and consumed on-site and never makes it to the grid. But in order to charge solar customers those additional transmission and delivery fees, the rules require all electric customers to shoulder the cost of installing a second meter in the homes and businesses with rooftop solar arrays to measure the total energy generated, not just the energy exported to the grid. 

Initially, Central Maine Power estimated that the cost of the new meters would be between $500 and $660, but later revised the cost to $1,410 per residential meter and $3,200 per commercial meter. In his request, Woodruff argued that the rate design for medium and large customers is primarily based on the magnitude of their power demand rather than their volumetric energy consumption, which provides little return for the investment in the new meters because the PUC’s nettable energy provisions are designed to recover revenue based on the solar project’s volumetric energy generation.

Before the vote on Dec. 12, PUC Chairman Mark Vannoy agreed with Woodruff that the rules don’t work for medium and large net metering customers, but he also reiterated his view that distributed energy sources like rooftop solar that use net energy billing shift the cost of the maintenance of power lines to other electricity customers.

“The rule is a sustainable path for distributed generation installation that ultimately contains in part, and eliminates in time, the cost shifting between customers,” said Vannoy.

The PUC also voted to require the utilities Central Maine Power and Emera Maine to provide a detailed accounting of the costs of complying with the rules, including the costs of the new meters. But the rules may not be around much longer, as Gov.-elect Janet Mills has made it a priority to eliminate them after she takes office in January. Woodruff said he was encouraged that the commission recognized that the cost of its rules are much higher than the estimates CMP initially provided.

“Responsible and informed decision making requires accurate data, and CMP clearly did not perform their due diligence in assessing the costs associated with this program,” he wrote. “As the state continues to modernize its regulatory policy to reflect technological changes in electrical generation and consumption, it is imperative that CMP work collaboratively — and in good faith — with other stakeholders in Maine to further avoid saddling ratepayers with unnecessary costs.”