philPhilip Mosenthal

Phil co-founded Optimal in 1996 after acting as Chief Consultant for XENERGY’s (now DNV GL) Mid-Atlantic office. With over 25 years of experience in all aspects of energy efficiency, Phil specializes in program design and planning for the business, institutional and industrial sectors. Phil has directly implemented programs and assisted numerous clients throughout the U.S. and internationally to develop and analyze efficiency portfolios, design leading edge programs, analyze integrated efficiency and supply-side resources, develop strategic models for large scale efficiency delivery, and develop evaluation plans and oversee evaluation activities. Phil currently serves advisory roles for the Massachusetts Energy Efficiency Advisory Council and Rhode Island Energy Efficiency Resource Management Council, among others. Phil has an M.S. in Energy Management and Policy and a B.A. in Architecture, both from the University of Pennsylvania.


Belliveau croppedEric Belliveau

Eric has been a Partner since 2000. He brings over thirty years of development, sales, operations and management experience in the energy, agricultural, construction and manufacturing industries to his work in energy efficiency. He specializes in efficiency program design, implementation support, direct install program approaches, financing strategies, and customer account management. Eric’s clients have included dozens of Program Administrators and efficiency stakeholders in several states and international jurisdictions. Among his roles, Eric is the lead consultant to the Massachusetts Energy Efficiency Advisory Council where he leads a team of national experts in advising the Council as it oversees implementation of one of the most advanced efficiency portfolios in the country. Eric has a B.A. in International Affairs with emphasis on Economics and German from the University of Maine, 1981. He is LEED accredited.


Jeff Loiter

Jeff is Optimal’s Corporate Development Manager. He has more than 16 years of consulting experience in environmental policy, energy, and natural resource issues. Jeff has assisted with the design and development of statewide and utility-specific efficiency programs in several jurisdictions and supports program implementation and ongoing program design and development for clients in New York and New England. He works primarily in the commercial sector on programs targeting electric, natural gas, and un-regulated fossil fuel consumption and specializes in developing solutions that fit the needs of specific customer segments and markets. Recently, he has provided analysis and testimony for the Sierra Club and other advocacy organizations in several cases before public utility commissions in Ohio, West Virginia, and Virginia. Jeff has an M.S. in Technology and Policy from the Massachusetts Institute of Technology and a B.S. with distinction in Civil and Environmental Engineering from Cornell University.


Managing Consultants

Mike Guerard

Mike joined Optimal in 2008. He has over 20 years of experience in the energy efficiency, green building and the renewable energy industry. He has developed and managed a wide-range of energy efficiency programs throughout New England and the Pacific Northwest; renewable energy and green building initiatives; and building science training and education forums. In addition to overseeing dozens of efficiency program staff, he has worked collaboratively with a wide range of stakeholders to achieve positive program results and significant energy savings. Working out of Optimal’s Rhode Island office, Mike provides critical cross-program development and implementation for a wide range of clients. He has a B.A from the University of Rhode Island.


Senior Consultants

George Lawrence

George has over 12 years of renewable energy and energy efficiency sales and consulting experience. His efficiency experience includes performing investment grade audits; planning, and program design; efficiency and renewable energy potential studies; research on renewable energy and energy efficiency technologies; and the design and implementation of strategic energy management programs. He currently supports commercial and industrial program implementation in Rhode Island for the RI Energy Efficiency Resources Management Council and does similar work in Massachusetts to coordinate C&I program efforts among the eight Program Administrators. Mr. Lawrence is a nationally recognized expert in snowmaking energy efficiency and has presented on this topic at many national conferences. He is also a Certified Practitioner of Energy Management Systems-Industrial, and is an expert in the implementation and maintenance of the ISO 50001 Energy Management standard. George graduated from Middlebury College with a degree in Physics (1989) and holds certifications as a Certified Energy Manager and a Certified Energy Auditor.


Matthew Socks, LC, CEM

Matt joined Optimal Energy in 2007 with a background in mechanical engineering, and has particular expertise in the fields of efficiency measure research methodology and characterization practices. Matt has served a leading role in conducting efficiency program engineering, economic analysis, and implementation assessments for clients across North America. He has been a primary contributor to numerous energy efficiency potential analyses and has served as technical lead in the development of energy efficiency savings estimation methodologies for a range of clients. Many of these projects required using novel approaches to address issues such as data availability, program delivery mechanisms, and the unique needs of each client. Matt holds a B.S. in Mechanical Engineering from the Massachusetts Institute of Technology.



SamSam Huntington

Sam joined Optimal Energy in 2009. He has worked on a variety of projects including the development of technical reference manuals, economic impact assessments, and numerous energy efficiency potential studies. From cost-effectiveness analysis to measure characterization to measure adoption rates, Sam is well versed in the methods of efficiency modeling and forecasting. He brings particular expertise to the areas of cost-effectiveness analysis, measure characterization, efficiency forecasting and forward capacity market participation for demand-side resources. Sam is based out of the Rhode Island office where he provides support to the state’s Energy Efficiency and Resource Management Council, as well as other clients in southern New England. He holds a B.S. in Mathematics from Colby College.


Clifford McDonald

Cliff first joined Optimal Energy in 2006. He has experience with various policy and technical issues relating to energy efficiency, renewable energy, and LEED certification. His energy experience includes potential studies, program design, cost effectiveness screenings, cash flow analysis, M&V protocol development, and implementation support. Recent projects at Optimal include completing reports on performance incentives and Pennsylvania’s Act 129; working on program design and PUC filings for New York, Washington D.C., and Rhode Island; analyzing the electric-sector GHG emission reductions under the NY State Climate Action Plan; and working on a potential analysis for NYPA. Cliff has a B.S. in Physics from Middlebury College.



Gretchen Calcagni

Gretchen joined Optimal in 2012. While in graduate school, she interned at Rocky Mountain Institute to help develop strategies for improving energy efficiency in the affordable housing sector. Her master’s project used quantitative data to explore household willingness to pay for improved energy efficiency in the rental housing market as well as policy solutions for barriers specific to this market. At Optimal, Gretchen provides research and analytical support on a range of projects including potential studies, program planning, and expert testimony. Gretchen received a Master of Public Policy from Duke University with a focus on energy and environmental policy and a B.A. in Sociology from the University of Virginia.


Craig Johnson

Craig received a Master of Science in Climate Science and Policy from Bard College – Center for Environmental Policy. During his time in graduate school, Craig interned with Environment Northeast, currently known as Acadia Center, where he helped to support many of the organizations core programs, including its sustainable transportation team. While at Environment Northeast, Craig also participated in various collaborative stakeholder meetings during the development process for Rhode Island’s State Energy Plan and National Grid’s 2014 Energy Efficiency Plan. For his Masters thesis, Craig modeled lifetime private costs of electric vehicles in comparison to hybrid and conventional vehicles and identified policy recommendations for growing the electric vehicle market. Mr. Johnson also holds a B.S. in Atmospheric Sciences from Lyndon State College.


Office Manager

April Clodgo

April provides Optimal and its clients with coordination, editing, presentation, bookkeeping and computer support.