David Littell David Littell

David Littell


Meet David, a nationally respected innovator in energy and environmental regulation and markets, backcountry skier and hiker who loves being in the water.

David Littell


207 228-7156 direct
207 774-1200 main
207 774-1127 facsimile

100 Middle Street
PO Box 9729
Portland, ME 04104-5029

Climate Change Practice Group



  • Chambers USA 2024 – Energy & Natural Resources (2 years ranked)
  • Distinguished Policy Scholar – University of Maine, Orono (2010)
  • Public Service for the Environment Award – Sierra Club, Maine Chapter, (2015)
  • Environmental Achievement Award – Maine Audubon for Implementation of Natural Resource Protection Habitat Rules (2007)


Littell, David P


Here’s why you’ll enjoy working with him.

David solves complex energy and environmental problems as private counsel, an energy and an environmental official. His well-honed sense of strategic direction, innovation and collaboration assists his clients in developing and achieving objectives—whether in specific cases or with concerted initiatives across multiple matters, dockets and transactions. He has testified in front of the FERC, the U.S. EPA, the Maine Legislature and New Hampshire Legislative Commission, numerous Public Utilities Commissions and speaks on energy and environmental issues for national and international audiences.

David is a highly sought-after energy industry expert and leader who understands energy market rules and state regulations, regulatory structures from FERC to state PUCs and energy offices, ISO/RTOs to vertically-integrated states, and how state environmental agencies work with EPA and how each applies federal and state rules and regulations.

David was also a key leader in designing, implementing, and running North America’s first market-based greenhouse gas regulatory system, the Regional Greenhouse Gas Initiative among 10 Northeastern and MidAtlantic States. The market-based program successfully put in place coordinated laws and rules in ten states and set up a hub administrative and technical assistance entity known as RGGI, Inc., based in New York City, which David chaired and served as an executive officer from 2008 to 2015.

David’s expertise spans a multitude of energy and environmental disciplines: power sector transformation, grid-scale and distributed energy resource integration, grid modernization, ISO/RTO market rules, environmental permitting of major projects under state and federal laws, environmental and energy compliance counseling under state and federal rules and regulations, complex environmental cleanup agreements, environmental due diligence and negotiations with lenders, bond and securities counsel in complex transactions, and complex litigation support.

Regardless of the size the project or case, David gets the job done—representing clients in proceedings and transactions, lending advice and providing expert counsel on strategic direction—to help them get where they need to go.

But that’s not all. David is also very experienced in:

  • Regulatory Structure and Power Market Design
  • Utility Rate Cases
  • Rate Design
  • Grid-scale and Distributed Renewable Energy
  • Power Sector Transformation and Resource Planning
  • Energy Efficiency
  • Distributed Energy Resources Integration and Planning
  • Air Quality and Climate Regulation
  • Water and Land permitting by federal, state and local authorities

In his former life, David was:

  • Principal at the Regulatory Assistance Project, (and he continues this work as a Senior Adviser to RAP)
  • Commissioner of the Maine Public Utilities Commission
  • Commissioner of the Maine Department of Environmental Protection
  • Chair of the New England Governors’ Environmental Committee and co-chair of the New England Governors’ and Eastern Canadian Premiers Committee on the Environment
  • A partner at a Portland law firm
  • A Lieutenant Commander in the US Navy Reserve

When David isn’t working, he is…

Enjoying Maine and New Hampshire’s outdoors backcountry skiing, hiking and swimming.


JD, Harvard Law School, cum laude
AB, Princeton University, magna cum laude, Phi Beta Kappa

Admitted to practice
State of Maine
State of Connecticut


Maine Audubon, Current Board of Trustees Chair, Executive Committee
New England Governors’ Committee on the Environment, former Chair
New England Governors’/Eastern Canadian Premiers Committee on the Environment, former co-chair
The Climate Registry, former Executive Committee and board member
Portland Trails, former President, Board member, Current Advisory Board Member