Our Clients Lead
the Nation in Energy Efficiency

  • Massachusetts (#1)
    8 years in a row
  • California (#2)
  • Rhode Island (#3)
  • Vermont (#4)
  • Connecticut (#5)
  • New York (#6)
  • Minnesota (#8)

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Prime Contractor for Delivering Cost-Effective EE Programs

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Broad Client Base

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Walking the Talk on Renewables

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Hiker and views from Camel’s Hump Mountain in Huntington, VT

Staff Spotlight: Gretchen Calcagni

As a consultant at Optimal, Gretchen provides research, analytical, and project management support for clients.

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Gretchen Calcagni head shot

LATEST NEWS

Energy efficiency co-benefits as a driver for multifamily retrofits

Staff Spotlight – Gretchen Calcagni, Consultant

Optimal Staff at Home Performance Conference

New York State Announces Dramatic Increase in Energy Efficiency, as Recommended by Optimal Energy Analysis

Funding Efficiency with Health Dollars

Nationally Recognized Energy Efficiency Consultants

Since 1996, Optimal Energy has provided a full range of energy efficiency consulting services to investor and municipally owned utilities, program administrators, state and federal energy offices, regulatory commissions, advisory councils, and advocacy groups. Read more…