Company lists · Data refreshed September 2026

Top 25 Green energy consulting firms based in the United States

Name: Green energy consulting firms based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 3, 2026 4,315 companies tracked

RevenueBase identified 4,315 company matches for green energy consulting firms associated with the United States as of September 2026 and tracks 52,375 professional contacts across them, including 22,256 with verified work emails and 21,356 with mobile numbers. Houston is the largest hub.

This list covers company matches for green energy consulting firms associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 3, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, 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 RevenueBase SmartSearch · Exact Recorded Sep 3, 2026 How this list was built

4,315Companies

52,375Contacts tracked

22,256Verified emails

21,356Mobile numbers

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The 25 largest green energy consulting firms based in the United States

Ranked by team size

Top 25 of 4,315 company matches for green energy consulting firms based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 3, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Westwood Professional Services	Exact match	Plano, LA, United StatesHQ recorded Sep 3, 2026	1,001-5,000	1,631 contacts →
	Exact match “At Westwood, our purpose is to create a better world for people through our work.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
2	Swca Environmental Consultants	Exact match	Phoenix, AZ, United StatesHQ recorded Sep 3, 2026	1,001-5,000	1,618 contacts →
	Exact match “Founded on a commitment to sound science and creative solutions, SWCA is a leader in environmental and management consulting services.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
3	Ameresco	Exact match	Framingham, MA, United StatesHQ recorded Sep 3, 2026	1,001-5,000	1,475 contacts →
	Exact match “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…” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
4	Willdan	Exact match	Anaheim, CA, United StatesHQ recorded Sep 3, 2026	1,001-5,000	838 contacts →
	Exact match “Willdan (NASDAQ: WLDN) provides professional consulting and technical services to utilities, public agencies and private industry throughout the United States.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
5	Energy Solutions	Exact match	Oakland, CA, United StatesHQ recorded Sep 3, 2026	201-500	768 contacts →
	Exact match “Our mission is simple - to combat climate change through market-based, cost-effective energy, carbon, and water management solutions that make big impacts.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
6	LUMIO	Exact match	Lehi, UT, United StatesHQ recorded Sep 3, 2026	5,001-10,000	727 contacts →
	Exact match “We’re on a mission to make power personal.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
7	Resource Innovations	Exact match	Half Moon Bay, AZ, United StatesHQ recorded Sep 3, 2026	501-1,000	724 contacts →
	Exact match “Resource Innovations (RI) is an energy transformation firm.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
8	Groundwater & Environmental Services, INC	Exact match	Wall Township, NY, United StatesHQ recorded Sep 3, 2026	201-500	452 contacts →
	Exact match “We are Groundwater & Environmental Services, Inc, better known as GES.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
9	TRIO	Exact match	Irvine, VA, United StatesHQ recorded Sep 3, 2026	201-500	382 contacts →
	Exact match “We are Trio – built from Edison Energy, Alfa Energy, and Altenex Energy.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
10	Energyscape Renewables	Exact match	Denver, United StatesHQ recorded Sep 3, 2026	501-1,000	376 contacts →
	Exact match “Established in 2019.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
11	P2s	Exact match	Long Beach, CA, United StatesHQ recorded Sep 3, 2026	201-500	370 contacts →
	Exact match “P2S has brought forward-thinking, sustainable engineering solutions to California, the Pacific Northwest, and beyond, for over 30 years.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
12	Takkion	Exact match	Evansville, WY, United StatesHQ recorded Sep 3, 2026	1,001-5,000	360 contacts →
	Exact match “TAKKION is Moving Energy Forward.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
13	Wendel Companies	Exact match	Williamsville, CT, United StatesHQ recorded Sep 3, 2026	201-500	354 contacts →
	Exact match “Wendel is an Architecture, Engineering, Energy Efficiency, and Construction Management Firm that delivers customized solutions and turnkey projects in innovative ways.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
14	Customized Energy Solutions	Exact match	Philadelphia, MA, United StatesHQ recorded Sep 3, 2026	201-500	335 contacts →
	Exact match “Customized Energy Solutions is at the forefront of competitive energy markets.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
15	3degrees Group, INC	Exact match	San Francisco, CA, United StatesHQ recorded Sep 3, 2026	201-500	325 contacts →
	Exact match “3Degrees is a leading global climate solutions provider, pioneer of environmental markets, and Certified B Corporation.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
16	Environmental Consulting & Technology, Inc. ECT	Exact match	Gainesville, FL, United StatesHQ recorded Sep 3, 2026	201-500	303 contacts →
	Exact match “Environmental Consulting & Technology, Inc.(ECT) is a multi-disciplinary environmental and sustainability consulting firm delivering strategy, permitting, design, and management…” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
17	Cascade Energy	Exact match	Portland, VT, United StatesHQ recorded Sep 3, 2026	201-500	290 contacts →
	Exact match “At Cascade Energy, we believe in better.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
18	Ecology And Environment, INC	Exact match	Lancaster, NY, United StatesHQ recorded Sep 3, 2026	5,001-10,000	277 contacts →
	Exact match “E&E is now WSP USA.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
19	Meraki Solar	Exact match	Pensacola, TX, United StatesHQ recorded Sep 3, 2026	1,001-5,000	274 contacts →
	Exact match “People.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
20	PSC Consulting	Exact match	Kirkland, MA, United StatesHQ recorded Sep 3, 2026	201-500	264 contacts →
	Exact match “We provide global renewable energy consulting services, focused on empowering clients to navigate the complexities of the energy transition.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
21	Merjent	Exact match	Minneapolis, MN, United StatesHQ recorded Sep 3, 2026	201-500	263 contacts →
	Exact match “Merjent is an environmental, restoration, and engineering consulting firm with a long history serving the energy industry.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
22	Mosaic	Exact match	Renton, WA, United StatesHQ recorded Sep 3, 2026	201-500	250 contacts →
	Exact match “Mosaic is a consulting firm that delivers custom solutions across the energy, utility, grid operations, and grid modernization space.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
23	Kleinschmidt Associates	Exact match	Pittsfield, ME, United StatesHQ recorded Sep 3, 2026	201-500	221 contacts →
	Exact match “At Kleinschmidt, we work primarily with energy companies and government agencies in North America to protect and enhance the environment without compromising performance.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
24	Dalkia Energy Solutions	Exact match	Beverly, MA, United StatesHQ recorded Sep 3, 2026	201-500	212 contacts →
	Exact match “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…” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase
25	PEG	Exact match	Fairfax, VA, United StatesHQ recorded Sep 3, 2026	201-500	211 contacts →
	Exact match “PEG presents a comprehensive capacity for the evaluation and understanding of a broad base of energy and environmental sustainability related programs, policies and initiatives.” Recorded in the RevenueBase company graph · Sep 3, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “green energy consulting firms”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 4,315 green energy consulting firms based in the United States

See the full list, filter by size, metro and specialty, and access 22,256 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Green energy consulting firms based in the United States at a glance

As of Sep 3, 2026

42.5%Verified-email coverage

40.8%Mobile-number coverage

12.1Average contacts per company

1-10Median size (employees)

4.3%Largest-city concentration · Houston

Sep 3, 2026Page data refreshed

Companies by employee count

1-10

2,732

11-50

1,150

51-200

314

201-500

501-1,000

1,001-5,000

5,001-10,000

Freshness & accuracy

How recently the business emails on this list were verified

Email last verified

00–30

1,81031–60

12,93461–90

7,41290–180

100180+

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Company records associated with the United States whose business descriptions match “green energy consulting firms” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
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 displayed company carries at least one verified work email. RevenueBase tracks 22,256 professional contacts with verified work emails across the full matched dataset. 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 3, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

Green energy consulting firms by metro

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “green energy consulting firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many green energy consulting firms are there based in the United States?

RevenueBase identified 4,315 company matches for green energy consulting firms associated with the United States as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Westwood Professional Services tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most green energy consulting firms?

Houston leads with 184 company records, followed by New York (162) and Denver (90).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 22,256 professional contacts with verified work emails tracked across these 4,315 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 3, 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 SmartSearch, 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.