| # | Company | Employees |
|---|---|---|
| 1 |
NRG Energynrg.com
Provides innovative natural gas, electricity, and smart home energy solutions to a diverse range of customers across North America. |
7,492 |
| 2 |
CenterPoint Energycenterpointenergy.com
An investor-owned energy delivery company with operations in electric transmission, power generation, and natural gas distribution serving over 7 million customers |
7,080 |
| 3 |
Calpinecalpine.com
A leading American electricity generator utilizing natural gas and geothermal resources, with a focus on clean, efficient power production for residential and commercial customers |
2,343 |
| 4 |
Direct Energydirectenergy.com
Retail provider of electricity, natural gas, and energy-related services for homes and businesses across North America, offering various plans. |
2,095 |
| 5 |
Just Energyjustenergy.com
A leading provider of simple and reliable energy services offering electricity, natural gas, and green energy options with competitive rates and rewards |
1,983 |
| 6 |
EthosEnergyethosenergy.com
Global services and tailored solutions for rotating equipment across power, oil, gas, industrial, and aerospace markets to ensure affordable and sustainable energy. |
1,939 |
| 7 |
CAMScamstex.com
Provides disciplined asset management and operations services, maximizing clients' value through operational performance, commercial optimization, and financial controls A reputation for creativity and flexibility |
1,712 |
| 8 |
SAE Towerssaetowers.com
A leading producer of steel lattice towers for high-voltage power transmission with engineering design, testing, and complete solutions for updated transmission infrastructure |
1,192 |
| 9 |
Dashiell Corporationdashiell.com
A national provider of technical services for various industries, specializing in medium and high voltage electrical infrastructure through engineering, construction, and testing services |
1,140 |
| 10 |
Reliant Energyreliant.com
A Texas-based company providing power to homes and businesses, committed to exceeding customer expectations with innovative energy solutions |
1,059 |
| 11 |
E Sourceesource.com
E Source helps utilities and cities improve sustainability and innovation through data science, market intelligence, consulting, and advisory services for industry leadership |
713 |
| 12 |
Vortex Companies - Trenchless Infrastructure Rehabilitation Solutionsvortexcompanies.com
The company provides advanced trenchless technologies and turnkey services to effectively renew water, sewer, and industrial infrastructure with experienced personnel |
505 |
| 13 |
Star Pipe Productsstarpipeproducts.com
Manufacturer of iron products, including Ductile Iron Pipe Fittings, Joint Restraints, AWWA Grooved Products, Castings, and OEM Products with distribution centers across North America |
491 |
| 14 |
ENGIE Resourcesengieresources.com
One of the largest providers of electricity and natural gas for businesses in the US, serving over 85,000 customers in 14 markets |
490 |
| 15 |
Corrpro Companies, Inc.azuria.com
Global leader in corrosion engineering, cathodic protection, and monitoring services for infrastructure preservation Offers consulting and engineering services to various industries |
444 |
| 16 |
GenOn Energygenon.com
A major competitive generator of wholesale electricity in the US with a portfolio of 23,700 megawatts, meeting the nation's electricity needs |
437 |
| 17 |
Spark Energysparkenergy.com
Provider of natural gas and electricity services for residential and commercial customers in competitive markets across the US, offering alternative energy choices and green products |
352 |
| 18 |
Dresser Utility Solutionsdresserutility.com
Global provider of metering, electronics, flow control, and distribution repair products for utility and industrial sectors, with an emphasis on water and wastewater treatment |
340 |
| 19 |
Green Mountain Energy Companygreenmountainenergy.com
A renewable energy retailer providing clean wind and solar energy plans, carbon offsets, and sustainability solutions to reduce carbon footprint |
319 |
| 20 |
Gexa Energygexaenergy.com
A leading retail electricity provider in Texas, part of a global renewable energy company, offering opportunities for energy visionaries |
295 |
| 21 | 262 | |
| 22 |
RRI Energy, Inc.rrienergy.com
This company operates power generation facilities in nine states, supplying electricity in competitive US markets with over 14,000 megawatts capacity |
254 |
| 23 |
Hudson Energyhudsonenergy.net
A leading energy supplier in North America, offering electricity, natural gas, and green energy solutions to commercial and residential customers since 2002 |
247 |
| 24 |
NextEra Energy Servicesnexteraenergyservices.com
A leading provider of renewable energy solutions, battery storage, and wholesale electricity generation, helping residential and large organizations achieve decarbonization and sustainability goals |
243 |
| 25 |
Champion Energy Serviceschampionenergyservices.com
One of the largest retail electricity providers in the US, serving residential, governmental, commercial, and industrial customers in multiple deregulated electric energy markets |
191 |
| 26 |
EDF Energy Servicesedftrading.com
EDF Energy North America specializes in providing energy solutions and services to customers in the North American region |
153 |
| 27 |
Utegration, a Cognizant companyutegration.com
Consulting and solutions provider specializing in SAP technology for energy and utilities, optimizing finance, reporting, customer experience, and asset operations. |
148 |
| 28 |
CenTriocentrioenergy.com
A leading provider of innovative, sustainable, and cost-efficient energy solutions for cities, campuses, and communities across the United States |
117 |
| 29 |
Entrust Energyentrustenergy.com
Retail energy company providing electricity and natural gas in deregulated markets with a focus on top customer service and competitive products |
105 |
| 30 |
Osaka Gas USAosakagasusa.com
The company develops, owns, and operates energy infrastructure to support stable and sustainable energy supply, with a focus on renewables and innovation |
96 |
| 31 | 91 | |
| 32 |
AEI Svcs LLCaeienergy.com
The company owns and operates power generation assets and natural gas businesses in emerging markets, focusing on reliability, local expertise, and world-class standards |
65 |
| 33 |
Iberdrola USAiberdrolatexas.com
Global leader in wind energy and electricity supply, offering renewable energy solutions in Texas sourced from local wind farms Serving millions worldwide |
38 |
| 34 |
AP Gas & Electric LLCapge.com
An energy supplier headquartered in Houston simplifying and making energy buying affordable for residential and commercial customers across multiple states |
29 |
| 35 |
Oasis Energyoasisenergy.com
A leading energy supplier offering electricity and natural gas with fixed price contracts, renewable energy options, and reliable customer service |
11 |
| 36 |
LifeEnergylifeenergy.com
A customer-focused energy provider prioritizing satisfaction, renewable energy, and innovation as integral parts of its unique business model |
9 |
| 37 |
Varsity Energyvarsityenergy.com
Energy company established in 2019, committed to supporting customers' energy needs while championing causes they care about, with a focus on sustainability |
6 |
| 38 |
CENT Energy, Inc.choiceenergynetwork.com
A leading utilities customer acquisition firm in North America, operating in all deregulated markets Specializing in procuring electricity and gas for businesses and residential customers |
5 |
| 39 |
Vientos Energyvientosenergy.com
An international energy company developing, owning, and operating renewable energy infrastructure in emerging markets, with offices in Houston, Buenos Aires, and Sao Paulo |
3 |
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Oct 9, 2026.
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