Company lists · Data refreshed September 2026

Top 25 Energy efficiency consultants based in the United States

Name: Energy efficiency consultants based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 16, 2026 1,605 companies tracked

RevenueBase identified 1,605 energy efficiency consultants headquartered in the United States as of September 2026 and tracks 23,367 professional contacts across them, including 11,320 with verified work emails. New York is the largest hub.

This list covers energy efficiency consultants 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 16, 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 16, 2026 86% judged on-target in blind review

1,605Companies

23,367Contacts tracked

11,320Verified emails

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The 25 largest energy efficiency consultants based in the United States

Ranked by team size

Top 25 of 1,605 energy efficiency consultants based in the United States, ranked by team size, largest first. Data refreshed Sep 16, 2026. RevenueBase Smart Search rates how each company's information relates to energy efficiency consultants: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Clearesult	Strong evidence	Austin, TX, United StatesHQ checked Sep 16, 2026	1,001-5,000	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 16, 2026
2	Ameresco	Partial evidence	Framingham, MA, United StatesHQ checked Sep 16, 2026	1,001-5,000	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 16, 2026
3	Willdan	Indirect evidence	Anaheim, CA, United StatesHQ checked Sep 16, 2026	1,001-5,000	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 16, 2026
4	Albireo Energy	Partial evidence	Edison, NJ, United StatesHQ checked Sep 16, 2026	1,001-5,000	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 16, 2026
5	TRIO	Partial evidence	Irvine, CA, United StatesHQ checked Sep 16, 2026	201-500	383 contacts →
	Partial evidence “We are Trio – built from Edison Energy, Alfa Energy, and Altenex Energy.” Source: RevenueBase Database · checked Sep 16, 2026
6	P2s	Indirect evidence	Long Beach, CA, United StatesHQ checked Sep 16, 2026	201-500	375 contacts →
	Indirect evidence “P2S has brought forward-thinking, sustainable engineering solutions to California, the Pacific Northwest, and beyond, for over 30 years.” Source: RevenueBase Database · checked Sep 16, 2026
7	NUS Consulting Group	Indirect evidence	Park Ridge, NJ, United StatesHQ checked Sep 16, 2026	201-500	336 contacts →
	Indirect evidence “National Utility Service, Inc.” Source: RevenueBase Database · checked Sep 16, 2026
8	Cascade Energy	Partial evidence	Portland, OR, United StatesHQ checked Sep 16, 2026	201-500	288 contacts →
	Partial evidence “At Cascade Energy, we believe in better.” Source: RevenueBase Database · checked Sep 16, 2026
9	Lake Superior Consulting	Partial evidence	Duluth, MN, United StatesHQ checked Sep 16, 2026	201-500	281 contacts →
	Partial evidence “We act as an extension of your team, combining deep energy expertise with seamless alignment to your processes to advance projects with confidence.” Source: RevenueBase Database · checked Sep 16, 2026
10	CMC Energy Services	Strong evidence	Fort Washington, PA, United StatesHQ checked Sep 16, 2026	201-500	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 16, 2026
11	Mantis Innovation	Partial evidence	Houston, TX, United StatesHQ checked Sep 16, 2026	201-500	233 contacts →
	Partial evidence “At Mantis Innovation, our experts provide data-driven, consultative services designed to optimize your facility, sustainability, and energy management strategies, while ultimately…” Source: RevenueBase Database · checked Sep 16, 2026
12	Lime Energy	Partial evidence	Newark, NJ, United StatesHQ checked Sep 16, 2026	201-500	233 contacts →
	Partial evidence “Lime Energy is building a new energy future.” Source: RevenueBase Database · checked Sep 16, 2026
13	PEG	Partial evidence	Fairfax, VA, United StatesHQ checked Sep 16, 2026	201-500	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 16, 2026
14	Dalkia Energy Solutions	Strong evidence	Beverly, MA, United StatesHQ checked Sep 16, 2026	201-500	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 16, 2026
15	Bright Power	Strong evidence	New York, NY, United StatesHQ checked Sep 16, 2026	51-200	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 16, 2026
16	Energy Management Collaborative EMC	Strong evidence	Minneapolis, MN, United StatesHQ checked Sep 16, 2026	201-500	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 16, 2026
17	Frontier Energy, INC	Partial evidence	Pleasanton, CA, United StatesHQ checked Sep 16, 2026	51-200	192 contacts →
	Partial evidence “Frontier Energy is a professional services firm that excels in market transformation.” Source: RevenueBase Database · checked Sep 16, 2026
18	Cenergistic	Partial evidence	Dallas, TX, United StatesHQ checked Sep 16, 2026	201-500	190 contacts →
	Partial evidence “At Cenergistic, energy conservation starts with people.” Source: RevenueBase Database · checked Sep 16, 2026
19	Nexant	Partial evidence	Half Moon Bay, CA, United StatesHQ checked Sep 16, 2026	201-500	183 contacts →
	Partial evidence “Resource Innovations now combined with Nexant is a substantially woman-owned, woman-led energy consulting firm dedicated to creating equal access to clean resources through…” Source: RevenueBase Database · checked Sep 16, 2026
20	Syserco, INC	Partial evidence	Fremont, CA, United StatesHQ checked Sep 16, 2026	51-200	164 contacts →
	Partial evidence “Syserco is an industry leader delivering Energy Management Solutions and Services to commercial and industrial facilities ranging from K-12 Schools, to High Rises, to…” Source: RevenueBase Database · checked Sep 16, 2026
21	Grumman Butkus Associates	Partial evidence	Evanston, IL, United StatesHQ checked Sep 16, 2026	51-200	153 contacts →
	Partial evidence “Grumman\|Butkus Associates (GBA) is a nationally recognized consulting engineering firm that specializes in mechanical, electrical and plumbing design services and energy and…” Source: RevenueBase Database · checked Sep 16, 2026
22	RISE	Strong evidence	Cranston, RI, United StatesHQ checked Sep 16, 2026	201-500	151 contacts →
	Strong evidence “RISE is a pioneer in the delivery of turnkey energy-efficiency services for residential, commercial and industrial facilities.” Source: RevenueBase Database · checked Sep 16, 2026
23	Steven Winter Associates	Strong evidence	Norwalk, CT, United StatesHQ checked Sep 16, 2026	51-200	142 contacts →
	Strong evidence “For over five decades, we’ve been at the forefront of transforming the built environment to be more energy efficient, accessible, healthy, and resilient.” Source: RevenueBase Database · checked Sep 16, 2026
24	STOK	Indirect evidence	San Francisco, CA, United StatesHQ checked Sep 16, 2026	51-200	141 contacts →
	Indirect evidence “Stok leads organizations to decarbonize now.” Source: RevenueBase Database · checked Sep 16, 2026
25	Concord Engineering Group, INC	Indirect evidence	Voorhees, NJ, United StatesHQ checked Sep 16, 2026	51-200	135 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 16, 2026

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 consultants. 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 consultants.
Partial evidence: Its own public description names part of energy efficiency consultants, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name energy efficiency consultants. 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 1,605 energy efficiency consultants based in the United States

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Energy efficiency consultants based in the United States at a glance

As of Sep 16, 2026

48.4%Verified-email coverage

14.6Average contacts per company

1-10Median size (employees)

3.9%Largest-city concentration · New York

Sep 16, 2026Page data refreshed

Companies by employee count

1-10

913

11-50

512

51-200

134

201-500

501-1,000

1,001-5,000

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 1,605 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 consultants, 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 consultants”. 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 consultants), 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 consultants, 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, 11,320 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 16, 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 consultants 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 consultants, 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 consultants are there based in the United States?

RevenueBase identified 1,605 energy efficiency consultants 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?

Clearesult, headquartered in Austin, tops this list with the largest team on record.

Which city has the most energy efficiency consultants?

New York leads with 62 headquartered companies, followed by Houston (46) and Denver (28).

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 11,320 verified decision-maker contacts tracked across these 1,605 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 16, 2026.

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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.