Company lists · Data refreshed September 2026

Top 25 Energy efficiency investment firms based in the United States

RevenueBase identified 674 energy efficiency investment firms headquartered in the United States as of September 2026 and tracks 8,649 professional contacts across them, including 3,492 with verified work emails and 3,628 with mobile numbers. New York is the largest hub.

This list covers energy efficiency investment firms 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 2, 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 RevenueBase Smart Search rating on every row Refreshed Sep 2, 2026 86% judged on-target in blind review
674Companies
8,649Contacts tracked
3,492Verified emails
3,628Mobile numbers
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The 25 largest energy efficiency investment firms based in the United States

Ranked by team size
Top 25 of 674 energy efficiency investment firms based in the United States, ranked by team size, largest first. Data refreshed Sep 2, 2026. RevenueBase Smart Search rates how each company's information relates to energy efficiency investment firms: 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.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Partial evidenceWestminster, CO, United States201-500484 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 2, 2026
2Strong evidenceShelton, CT, United States201-500359 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 2, 2026
3Partial evidenceNewark, NJ, United States201-500233 contacts →

Partial evidence

“Lime Energy is building a new energy future.”

Source: RevenueBase Database · checked Sep 2, 2026
4Strong evidenceBeverly, MA, United States201-500212 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 2, 2026
5Strong evidenceNew York, NY, United States51-200200 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 2, 2026
6Strong evidenceMinneapolis, MN, United States201-500197 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 2, 2026
7Partial evidenceNew York, NY, United States51-200194 contacts →

Partial evidence

“HASI invests in sustainable infrastructure assets advancing the energy transition.”

Source: RevenueBase Database · checked Sep 2, 2026
8Strong evidenceOakland, CA, United States51-200189 contacts →

Strong evidence

“Renew Financial pioneered the residential Property Assessed Clean Energy (PACE) program, an innovative financing solution that helps homeowners invest in energy efficiency, water…”

Source: RevenueBase Database · checked Sep 2, 2026
9Strong evidenceCranston, RI, United States201-500151 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 2, 2026
10Partial evidenceSan Francisco, CA, United States51-200135 contacts →

Partial evidence

Energy Impact Partners LP (EIP) is a global energy technology investor with a proprietary model designed to drive innovation.”

Source: RevenueBase Database · checked Sep 2, 2026
11Strong evidenceFresno, CA, United States501-1,000124 contacts →

Strong evidence

“Synergy Companies is the largest energy services companies in California and provides a comprehensive approach to energy efficiency and environmental solutions in both the…”

Source: RevenueBase Database · checked Sep 2, 2026
12Partial evidenceNew York City, NY, United States51-200123 contacts →

Partial evidence

“ECP (Energy Capital Partners) is an investor in critical infrastructure focused on electrification, decarbonization, reliability and sustainability.”

Source: RevenueBase Database · checked Sep 2, 2026
13Partial evidenceLa Crosse, WI, United States51-200120 contacts →

Partial evidence

“Michaels Energy is a veteran-owned energy consulting firm that exists to help businesses minimize waste and maximize value.”

Source: RevenueBase Database · checked Sep 2, 2026
14Strong evidencePhoenix, AZ, United States51-200118 contacts →

Strong evidence

“Erus Energy helps building owners evaluate and finance investments in Solar Energy and other energy saving equipment.”

Source: RevenueBase Database · checked Sep 2, 2026
15Strong evidenceIthaca, NY, United States51-200114 contacts →

Strong evidence

“PSD is an energy efficiency services and technology company.”

Source: RevenueBase Database · checked Sep 2, 2026
16Partial evidenceNew York, NY, United States51-200103 contacts →

Partial evidence

“Speed and efficiency are the cornerstones of climate finance.”

Source: RevenueBase Database · checked Sep 2, 2026
17Partial evidenceChicago, IL, United States51-20084 contacts →

Partial evidence

“Pacific Energy Concepts™ (PEC) is North America’s most innovative energy optimization company.”

Source: RevenueBase Database · checked Sep 2, 2026
18Strong evidenceNew York, NY, United States51-20071 contacts →

Strong evidence

“CodeGreen is a leading national sustainability and energy efficiency consulting firm.”

Source: RevenueBase Database · checked Sep 2, 2026
19Strong evidenceNew York, NY, United States1,001-5,00065 contacts →

Strong evidence

“Founded in 2003, ThomasLloyd is a vertically integrated sustainable energy and technology solutions provider, integrating development, investment, operations, and technology on a…”

Source: RevenueBase Database · checked Sep 2, 2026
20Indirect evidenceFort Lauderdale, FL, United States51-20061 contacts →

Indirect evidence

“What Do We Do?”

Source: RevenueBase Database · checked Sep 2, 2026
21Strong evidencePortland, OR, United States51-20060 contacts →

Strong evidence

Energy 350 takes pride in performing high quality energy studies and energy efficiency related services for end users as well as program administrators.”

Source: RevenueBase Database · checked Sep 2, 2026
22Partial evidenceLos Angeles, CA, United States51-20056 contacts →

Partial evidence

“Partner Energy, Inc.”

Source: RevenueBase Database · checked Sep 2, 2026
23Partial evidenceAtlanta, GA, United States51-20053 contacts →

Partial evidence

“FCI provides impactful energy solutions at every point on the delivery chain-from system design to program development to marketing and installation.”

Source: RevenueBase Database · checked Sep 2, 2026
24Strong evidencePlano, TX, United States51-20052 contacts →

Strong evidence

“At Mayer, we are committed to revolutionizing the way energy is harnessed and consumed, delivering innovative solar and energy efficiency solutions to homes and businesses across…”

Source: RevenueBase Database · checked Sep 2, 2026
25Strong evidenceOshkosh, WI, United States201-50050 contacts →

Strong evidence

“ECM is one of the nation’s leading providers of energy efficiency retrofit technologies.”

Source: RevenueBase Database · checked Sep 2, 2026

Showing 25 of 674 energy efficiency investment firms based in the United States

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Energy efficiency investment firms based in the United States at a glance

As of Sep 2, 2026
40.4%Verified-email coverage
41.9%Mobile-number coverage
12.8Average contacts per company
1-10Median size (employees)
6.1%Largest-city concentration · New York
Sep 2, 2026Page data refreshed

Companies by employee count

1-10
366
11-50
227
51-200
62
201-500
12
501-1,000
5
1,001-5,000
2

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 investment firms, 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 investment firms”. 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 investment firms), 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 investment firms, 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, 3,492 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 2, 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 investment firms 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 investment firms, 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 investment firms are there based in the United States?

RevenueBase identified 674 energy efficiency investment firms 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?

Noresco, headquartered in Westminster, tops this list with the largest team on record.

Which city has the most energy efficiency investment firms?

New York leads with 41 headquartered companies, followed by Houston (25) and San Francisco (18).

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 3,492 verified decision-maker contacts tracked across these 674 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 2, 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.