Maine allows customers with qualifying distributed electric generation to net the power they produce against their consumption of power from the grid. The Maine Public Utilities Commission adopted rules governing this "net energy billing" or net metering arrangement. Most customer-scale solar photovoltaic projects in Maine rely on net energy billing, including those located in the service territory of utility Central Maine Power or CMP.
One provision of those rules, found in Section 3(J) of Chapter 313, provides for regulatory review of net metering once a utility reaches a threshold of installed net metering capacity:
A transmission and distribution utility shall notify the Commission if the cumulative capacity of generating facilities subject to the provisions of this Chapter reaches 1.0 percent of its peak demand. Upon notification, the Commission will review this Chapter to determine whether net energy billing pursuant to this Chapter should continue or be modified.On January 14, 2016, CMP filed a letter with the Maine Commission requesting that the Commission undertake the review of net energy billing described in Section 3(J) of Chapter 313. In support of that request, CMP notes:
As of the end of calendar year 2015, the cumulative capacity of the generating facilities for which CMP has net energy billing agreements under Chapter 313 is approximately 1.04% of CMP’s annual peak demand. The 1.04% is based upon the ratio of 16.261/1,565.300, where the numerator is the megawatts of nameplate capacity of contracted net energy billing facilities and the denominator represents the Company’s 2015 annual hourly peak demand.The Maine Public Utilities Commission has docketed CMP's request as 2015-00008. At the same time, the Commission is concluding a months-long legislatively mandated stakeholder process to consider alternatives to net energy billing, after which the Commission is scheduled to present a report to the state's legislative energy committee.
These two proceedings have different direct origins, but their effects could be similar. CMP's letter under Chapter 313 says it was triggered by growth of enrolled net metering capacity, while the stakeholder process resulted from a direct legislative requirement. Nevertheless both proceedings may affect the future of net metering in Maine.