Maine PUC Establishes Integrated Grid Planning Process

On July 12, 2024, the Maine Public Utilities Commission (PUC) released the final Order in its Integrated Grid Planning (IGP) proceeding. The Order is the culmination of several years’ worth of effort from the PUC, the Legislature, Maine’s investor-owned utilities, nonprofit advocacy groups (including Acadia Center), the Governor’s Energy Office, the Office of the Public Advocate, Efficiency Maine Trust, and numerous other entities.

With its recent Order, the PUC lays the foundation for a formal 18–month grid planning process, which will occur every five years. As part of their planning efforts, Central Maine Power and Versant Power must develop a 10-year vision for Maine’s electric grid, as well as an investment roadmap for improving reliability and resiliency while keeping costs affordable and enabling the cost-effective achievement of Maine’s climate policies and greenhouse gas emissions reductions requirements. 

Integrated Grid Plans Offer a More Holistic View of Future Utility Investments

The required grid plans are intended to ensure that Maine’s investor-owned utilities are well prepared to meet the challenges of climate change and the needs of a rapid transition to clean energy. In developing their grid plans, the utilities are directed to place equity and environmental justice impacts more centrally within their planning efforts and to ensure greater transparency and stakeholder input compared to previous utility planning processes. 

The PUC directs the utilities to prioritize load flexibility through measures such as demand response that can shift energy demand to times of day when electricity is less expensive and less polluting. These kinds of load flexibility programs can enable more dynamic grid operations and reductions in peak demand. The plans must also identify strategies to accelerate the deployment of non-wires alternatives (NWA) like energy storage, which are often cleaner and cheaper than traditional infrastructure investments. And the utilities must develop a roadmap for more advanced modeling of the distribution system, which will allow for detailed analysis of the impact of electric vehicles, heat pumps, and other distributed energy resources on the grid.  

After the completion of an extensive modeling and forecasting process, the utilities will conduct a broad assessment of possible solutions to meet anticipated grid needs, including both traditional investments and a wide range of clean and distributed energy alternatives. The solutions identified in the grid plans will inform the utilities’ subsequent investment proposals, which they will put forth in rate cases before the PUC.  

Next Steps

Despite the PUC’s Order, there are still key questions left to be answered, such as the exact process for stakeholder input and review throughout the 18-month planning period, as well as concretely defining the equity and environmental justice metrics to be used in the solution evaluation scorecard. While advocates pushed for clear definitions throughout the PUC proceeding, the Order leaves it up to the utilities and other stakeholders to determine which definitions will be included and how the equity and environmental justice assessment will be conducted.

While the Integrated Grid Planning process will not address every challenge relevant to Maine’s energy and utility sectors, the PUC’s recent Order is an important milestone and marks a pivotal moment in the state’s clean energy transition. Acadia Center looks forward to continuing to work with the PUC, utilities, and other stakeholders as we finalize the details of the planning process and set the course for the years to come.