Maine considers community solar rules

As Maine utility regulators consider changes to the state’s net metering rule for solar panels and other customer-owned generation, revisions proposed by the Public Utilities Commission could change how consumers can participate in community and shared ownership solar projects.

For years, the Maine Public Utilities Commission’s rules have allowed “net energy billing,” a metering and billing mechanism that promotes the development and operation of smaller renewable generation facilities. Net metering is responsible for nearly all customer-owned solar power projects developed in Maine to date, including a handful of shared ownership or community solar farms. But as utility Central Maine Power Company reported that its customers' net metering reached 1% of peak load last year, the Commission launched a process to consider revisions to its net energy billing rules.

On September 14, 2016, the Commission released a Notice of Rulemaking along with proposed amendments to its rule. As proposed by the Commission, the amended rule would expand net energy billing in Maine in several ways. It would increases the size cap for an eligible facility by 50%, from 660 kilowatts to one megawatt. It would also recognize four different types of net energy billing arrangements that would be allowed: individual customer; customer leases; shared ownership; and community NEB.

Under the shared ownership model, each participating customer must have a shared ownership interest in the eligible facility under which the customers have joint responsibility for the costs of the shared ownership facility and have rights to the output of the shared ownership facility in proportion to their cost responsibilities. Under shared ownership net energy billing, the transmission and distribution utility would allocate the nettable energy of the shared ownership facility to customers in proportion to each customer’s ownership interest in the eligible facility.

The proposed rule would also explicitly allow for “community” net energy billing, a model that the Commission recognized as “increasing as a means to promote smaller solar installations.” The proposal suggests that community projects would have similarities to shared ownership projects, with additional registration and consumer protection provisions, but potentially with different ownership requirements.

The case over the rule change’s adoption remains pending for now. While some elements of the proposal would expand net metering opportunities, the proposal would also ratchet down the amount of energy that new projects could net against their T&D bill, from 100% in 2016 to 0% for new NEB customers after 2025. Elements of the Commission’s proposal remain controversial. Nevertheless the Commission’s proposal suggests a potential direction for future community solar projects in Maine.