Company lists · Data refreshed September 2026

Top 25 Geothermal energy contractors based in the United States

RevenueBase identified 473 geothermal energy contractors headquartered in the United States as of September 2026 and tracks 5,873 professional contacts across them, including 2,195 with verified work emails. Houston is the largest hub.

This list covers geothermal energy contractors 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
473Companies
5,873Contacts tracked
2,195Verified emails
Explore this list → Free signup · no credit card · 500 free credits

The 25 largest geothermal energy contractors based in the United States

Ranked by team size
Top 25 of 473 geothermal energy contractors 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 geothermal energy contractors: 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
1Indirect evidenceReno, NV, United StatesHQ checked Sep 16, 20261,001-5,0001,281 contacts →

Indirect evidence

“With over five decades of experience, Ormat Technologies, Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
2Strong evidenceFargo, ND, United StatesHQ checked Sep 16, 20261,001-5,000933 contacts →

Strong evidence

“Wanzek Construction, Inc, a MasTec Renewables company, is a leading general construction contractor and clean energy services company headquartered in Fargo, North Dakota.”

Source: RevenueBase Database · checked Sep 16, 2026
3Indirect evidenceFort Wayne, IN, United StatesHQ checked Sep 16, 2026201-500224 contacts →

Indirect evidence

“WaterFurnace International, Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
4Strong evidenceHouston, CA, United StatesHQ checked Sep 16, 202651-200213 contacts →

Strong evidence

“Fervo Energy provides 24/7 carbon-free energy through the development of next-generation geothermal power.”

Source: RevenueBase Database · checked Sep 16, 2026
5Strong evidenceMount Kisco, NY, United StatesHQ checked Sep 16, 202651-200118 contacts →

Strong evidence

“Dandelion Energy is the nation’s leading residential geothermal provider, on a mission to make the world’s most efficient heating and cooling technology accessible to everyone.”

Source: RevenueBase Database · checked Sep 16, 2026
6Partial evidenceArmonk, NY, United StatesHQ checked Sep 16, 202651-200108 contacts →

Partial evidence

“Brightcore Energy is a leading renewable energy solutions provider serving commercial, institutional, and government clients.”

Source: RevenueBase Database · checked Sep 16, 2026
7Partial evidencePhelps, NY, United StatesHQ checked Sep 16, 202651-20082 contacts →

Partial evidence

“Halco is a highly accredited, national award-winning contractor that has been providing high-quality solutions to residential and commercial clients since 1984.”

Source: RevenueBase Database · checked Sep 16, 2026
8Strong evidenceGreenville, IL, United StatesHQ checked Sep 16, 202651-20081 contacts →

Strong evidence

Enertech Global is a leading manufacturer and visionary in the geothermal heating and cooling industry.”

Source: RevenueBase Database · checked Sep 16, 2026
9Indirect evidenceKahului, HI, United StatesHQ checked Sep 16, 2026201-50066 contacts →

Indirect evidence

“Alpha Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
10Indirect evidenceMurfreesboro, TN, United StatesHQ checked Sep 16, 202651-20065 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 16, 2026
11Partial evidenceHouston, MA, United StatesHQ checked Sep 16, 202651-20062 contacts →

Partial evidence

“Quaise develops superhot geothermal power plants for a terawatt-scale world.”

Source: RevenueBase Database · checked Sep 16, 2026
12Strong evidenceMount Vernon, NY, United StatesHQ checked Sep 16, 202651-20057 contacts →

Strong evidence

“Dual Fuel is a Licensed Master Plumber, General Contractor, NYSERDA Real Time Energy Management (RTEM) System and Service Provider, Coned C&I Partner, Coned Multifamily Partner…”

Source: RevenueBase Database · checked Sep 16, 2026
13Indirect evidenceLaurel, MD, United StatesHQ checked Sep 16, 202651-20052 contacts →

Indirect evidence

“We at Allied Well Drilling are a full service commercial and residential gethermal heating/cooling system installer, specializing in vertically drilled closed loop systems.”

Source: RevenueBase Database · checked Sep 16, 2026
14Partial evidenceWheat Ridge, CO, United StatesHQ checked Sep 16, 202611-5050 contacts →

Partial evidence

“As Denver HVAC specialists and geothermal system experts, we believe in doing things right!”

Source: RevenueBase Database · checked Sep 16, 2026
15Partial evidenceAiea, HI, United StatesHQ checked Sep 16, 202651-20044 contacts →

Partial evidence

“Hawaii Energy Systems provides turn-key energy solutions for commercial, industrial and institutional customers throughout the Hawaiian Islands plus Guam, Northern Mariana…”

Source: RevenueBase Database · checked Sep 16, 2026
16Partial evidenceWillow Street, PA, United StatesHQ checked Sep 16, 202651-20039 contacts →

Partial evidence

“Plumbing, HVAC, and Electrical Service Contractor in the following markets- Residential & commercial service & repairs of mechanical systems of all nature - Bathroom remodeling &…”

Source: RevenueBase Database · checked Sep 16, 2026
17Partial evidenceNew Brighton, MN, United StatesHQ checked Sep 16, 202611-5038 contacts →

Partial evidence

“Darcy Solutions is on a mission to put Geothermal Everywhere.”

Source: RevenueBase Database · checked Sep 16, 2026
18Strong evidencePalo Alto, CA, United StatesHQ checked Sep 16, 202611-5034 contacts →

Strong evidence

“XGS Energy is a geothermal energy company founded and headquartered in Palo Alto, CA.”

Source: RevenueBase Database · checked Sep 16, 2026
19Indirect evidenceRochester, NY, United StatesHQ checked Sep 16, 202651-20032 contacts →

Indirect evidence

“John Betlem started the company in 1941, and John Betlem Heating & Cooling, Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
20Indirect evidenceFort Collins, CO, United StatesHQ checked Sep 16, 202651-20032 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 16, 2026
21Strong evidenceHauppauge, NY, United StatesHQ checked Sep 16, 202651-20029 contacts →

Strong evidence

“Sunrise Power Solutions is a clean energy contractor providing innovative energy solutions to our customers in the key markets that we serve: municipal, K12 educational and…”

Source: RevenueBase Database · checked Sep 16, 2026
22Partial evidenceFort Worth, TX, United StatesHQ checked Sep 16, 202651-20029 contacts →

Partial evidence

“Since 1974, Century Mechanical Contractors, Inc.”

Source: RevenueBase Database · checked Sep 16, 2026
23Partial evidenceGrand Rapids, MI, United StatesHQ checked Sep 16, 202611-5028 contacts →

Partial evidence

Geothermal Systems are becoming a critical component in the effort to make buildings more environmentally friendly.”

Source: RevenueBase Database · checked Sep 16, 2026
24Indirect evidenceDes Plaines, IL, United StatesHQ checked Sep 16, 202611-5027 contacts →

Indirect evidence

“Projeo provides geoscience and reservoir engineering technical expertise, experienced operational and field supervision services, and integrated project management for your…”

Source: RevenueBase Database · checked Sep 16, 2026
25Strong evidenceAustin, TX, United StatesHQ checked Sep 16, 202611-5027 contacts →

Strong evidence

“Our mission is to transform the heating & cooling of buildings, using geothermal energy to radically reduce costs for people and the environment.”

Source: RevenueBase Database · checked Sep 16, 2026

Showing 25 of 473 geothermal energy contractors based in the United States

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 2,195 reachable decision-makers.

Free signup · no credit card

View the full list →

Geothermal energy contractors based in the United States at a glance

As of Sep 16, 2026
37.4%Verified-email coverage
12.4Average contacts per company
1-10Median size (employees)
3.0%Largest-city concentration · Houston
Sep 16, 2026Page data refreshed

Companies by employee count

1-10
244
11-50
188
51-200
35
201-500
3
1,001-5,000
2

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 473 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 geothermal energy contractors, 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 “geothermal energy contractors”. 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 geothermal energy contractors), 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 geothermal energy contractors, 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, 2,195 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.

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 geothermal energy contractors, 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 geothermal energy contractors are there based in the United States?

RevenueBase identified 473 geothermal energy contractors 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?

Ormat Technologies, INC, headquartered in Reno, tops this list with the largest team on record.

Which city has the most geothermal energy contractors?

Houston leads with 14 headquartered companies, followed by Austin (7) and Reno (7).

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 2,195 verified decision-maker contacts tracked across these 473 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.

Ready to reach these companies? Verified emails and direct dials for all 473 geothermal energy contractors based in the United States. Start with a free account, no credit card.

Download this list →

Related 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.