Company lists · Data refreshed September 2026
Top 25 Energy efficiency companies based in the United States
RevenueBase identified 2,440 energy efficiency companies headquartered in the United States as of September 2026 and tracks 38,939 professional contacts across them, including 17,690 with verified work emails. New York is the largest hub.
This list covers energy efficiency companies headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 15, 2026.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest energy efficiency companies based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 2,213 contacts → | ||||
Partial evidence “We're a national construction and energy services company dedicated to innovating the waste and climate harm out of the built environment.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 2 | 2,121 contacts → | ||||
Strong evidence “CLEAResult is the largest provider of energy efficiency, energy transition and energy sustainability services in North America.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 3 | 1,383 contacts → | ||||
Partial evidence “Ameresco, Inc.(NYSE:AMRC) is a leading energy infrastructure solutions provider dedicated to helping customers reduce costs, enhance resilience, and decarbonize to net zero in the…” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 4 | 851 contacts → | ||||
Indirect evidence “Willdan (NASDAQ: WLDN) provides professional consulting and technical services to utilities, public agencies and private industry throughout the United States.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 5 | 772 contacts → | ||||
Partial evidence “Our mission is simple - to combat climate change through market-based, cost-effective energy, carbon, and water management solutions that make big impacts.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 6 | 733 contacts → | ||||
Partial evidence “Resource Innovations (RI) is an energy transformation firm.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 7 | 669 contacts → | ||||
Partial evidence “Albireo Energy is a leading independent building controls and energy services provider recognized by customers for creating intelligent, high-performance buildings.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 8 | 481 contacts → | ||||
Partial evidence “NORESCO, a part of Carrier Global Corporation, helps customers modernize aging building systems and upgrade energy and water infrastructure to meet evolving demands.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 9 | 383 contacts → | ||||
Partial evidence “Veregy is an award-winning NAESCO-Accredited decarbonization company focusing on accelerating and simplifying the Energy Transition.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 10 | 383 contacts → | ||||
Partial evidence “We are Trio – built from Edison Energy, Alfa Energy, and Altenex Energy.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 11 | 366 contacts → | ||||
Strong evidence “Budderfly is redefining how energy efficiency, resilience, and grid participation can work together across America’s commercial sector.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 12 | 356 contacts → | ||||
Strong evidence “At HomeWorks Energy, our mission is simple, literally: Energy Efficiency, Simplified.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 13 | 355 contacts → | ||||
Strong evidence “Wendel is an Architecture, Engineering, Energy Efficiency, and Construction Management Firm that delivers customized solutions and turnkey projects in innovative ways.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 14 | 336 contacts → | ||||
Indirect evidence “National Utility Service, Inc.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 15 | 288 contacts → | ||||
Partial evidence “At Cascade Energy, we believe in better.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 16 | 252 contacts → | ||||
Strong evidence “CMC Energy Services is a woman-owned full-service energy efficiency company with nearly 50 years of experience delivering value-based energy conservation services.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 17 | 251 contacts → | ||||
Partial evidence “Lane Valente Industries offers a broad range of solutions that help multi-site organizations reduce costs through energy reduction, facility maintenance and value engineering.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 18 | 233 contacts → | ||||
Partial evidence “Lime Energy is building a new energy future.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 19 | 216 contacts → | ||||
Strong evidence “Walker-Miller Energy Services (Walker-Miller), one of the largest African American and woman owned energy efficiency companies in the United States, changes lives through energy.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 20 | 214 contacts → | ||||
Partial evidence “PEG presents a comprehensive capacity for the evaluation and understanding of a broad base of energy and environmental sustainability related programs, policies and initiatives.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 21 | 210 contacts → | ||||
Strong evidence “Dalkia Energy Solutions, a subsidiary of the EDF (Électricité de France) Group, is a national leader in energy efficiency and sustainability for commercial, industrial, and…” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 22 | 205 contacts → | ||||
Strong evidence “Bright Power is a leading provider of energy efficiency and decarbonization solutions for the real estate industry.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 23 | 203 contacts → | ||||
Partial evidence “Motive Energy transforms how businesses source, store, convert, move, and manage their energy through end-to-end solutions that empower customers to take control of their energy.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 24 | 193 contacts → | ||||
Strong evidence “EMC manages and scales turnkey energy efficiency solutions for Fortune 500 clients across their North American portfolios.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
| 25 | 192 contacts → | ||||
Partial evidence “Frontier Energy is a professional services firm that excels in market transformation.” Source: RevenueBase Database · checked Sep 15, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: energy efficiency companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names energy efficiency companies.
- Partial evidence
- Its own public description names part of energy efficiency companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name energy efficiency companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 2,440 energy efficiency companies based in the United States
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 17,690 reachable decision-makers.
Free signup · no credit card
Energy efficiency companies based in the United States at a glance
As of Sep 15, 2026Companies by employee count
Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 2,440 companies.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among energy efficiency companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- What qualifies
- Companies headquartered in the United States whose own description of what they do matches “energy efficiency companies”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names energy efficiency companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among energy efficiency companies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 17,690 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 15, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Energy efficiency companies by metro
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names energy efficiency companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many energy efficiency companies are there based in the United States?
RevenueBase identified 2,440 energy efficiency companies headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
Mckinstry, headquartered in Seattle, tops this list with the largest team on record.
Which city has the most energy efficiency companies?
New York leads with 93 headquartered companies, followed by Houston (71) and Atlanta (40).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 17,690 verified decision-maker contacts tracked across these 2,440 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 15, 2026.
Ready to reach these companies? Verified emails and direct dials for all 2,440 energy efficiency companies based in the United States. Start with a free account, no credit card.
Download this list →Related lists
Energy efficiency companies by geography
- Energy efficiency companies based in Rio De Janeiro, Brazil
- Energy efficiency companies based in Sao Paulo, Brazil
- Energy efficiency companies based in Milan, Italy
- Energy efficiency companies based in Milano, Italy
- Energy efficiency companies based in Roma, Italy
- Energy efficiency companies based in Torino, Italy
- Energy efficiency companies based in Barcelona, Spain
- Energy efficiency companies based in Madrid, Spain
- Energy efficiency companies based in Valencia, Spain
- Energy efficiency companies based in Atlanta, United States
- Energy efficiency companies based in Austin, United States
- Energy efficiency companies based in Chicago, United States
Browse the directory
Browse: Companies home · All United States lists · All Energy efficiency companies lists · New lists
About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Energy efficiency companies based in Rio De Janeiro, Brazil
- Energy efficiency companies based in Sao Paulo, Brazil
- Energy efficiency companies based in Milan, Italy
- Energy efficiency companies based in Milano, Italy
- Energy efficiency companies based in Roma, Italy
- Energy efficiency companies based in Torino, Italy