# 30 leading energy companies in the Loire-Atlantique department
Tamtam tracks 40 energy companies headquartered in the Loire-Atlantique department. This list ranks the 30 largest by number of employees on LinkedIn, led by Chantiers de l'Atlantique, Sercel and AS 24. Their median headcount is 42. Half of them were founded in 2010 or later. The most common headquarters are Nantes (13), Saint-Herblain (3) and Bouguenais (2).
The energy sector in Loire-Atlantique features a mix of established industrial players and younger companies focused on renewable energy. Chantiers de l'Atlantique, founded in 1861, is a marine construction company building complex ships. Sercel provides subsurface measurement solutions, while AS 24 specializes in fuel distribution for heavy goods vehicles. Lhyfe focuses on green industrial hydrogen production, and Vaillant Group France develops heating and cooling systems using renewable energy.
A notable pattern is the concentration of companies in Nantes, which serves as a hub for both traditional and emerging energy businesses. The area also shows a strong emphasis on renewable energy, with firms like Dome Solar manufacturing photovoltaic mounting systems, Beem offering solar solutions for homes, and Armor Battery Films enhancing lithium-ion battery performance.
馃嚝馃嚪 Loire-Atlantique 路 30 companies 路 Updated Nov 14, 2026
| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [Chantiers de l'Atlantique](https://www.tamtam.ai/c/chantiers-de-l-atlantique) (chantiers-atlantique.com)
Marine construction company, building complex ships and marine installations, including passenger ships and substations. Global leader in design, manufacturing, and commissioning of innovative, environmentally friendly vessels. | Shipbuilding | 馃嚝馃嚪 Saint-Nazaire | 2,472 | 1861 |
| 2 | [Sercel](https://www.tamtam.ai/c/sercel) (sercel.com)
Leading provider of high-standard subsurface measurement and data solutions for natural resources, infrastructure monitoring, energy transition, and defense sectors since 1956. | Manufacturing | 馃嚝馃嚪 Carquefou | 942 | 1956 |
| 3 | [AS 24](https://www.tamtam.ai/c/as-24) (as24.com)
Specialized fuel distribution network for heavy goods vehicles across 29 countries, offering secure transactions, competitive prices, and dedicated stations. | Oil and Gas | 馃嚝馃嚪 Saint-Herblain | 380 | 1988 |
| 4 | [MADIC group](https://www.tamtam.ai/c/madic-group) (groupe.madic.com)
innovative French industrialist in electronic payment, petroleum equipment, services, and Digital Media communication, with a focus on sustainable development values. | Oil and Gas | 馃嚝馃嚪 Nantes | 267 | 1971 |
| 5 | [MADIC SAS](https://www.tamtam.ai/c/madic-sas) (groupe.madic.com)
A French leader in payment and petrol equipment and services, providing customized solutions for gas stations, renovations, and compliance updates across France, Spain, and Belgium | Oil and Gas | 馃嚝馃嚪 Nantes | 237 | 1971 |
| 6 | [Lhyfe](https://www.tamtam.ai/c/lhyfe) (lhyfe.com)
Pure player deploying modular, 100% green industrial hydrogen production plants for mobility and industry, clean and accessible. | Renewable Energy Power Generation | 馃嚝馃嚪 Nantes | 217 | 2017 |
| 7 | [Vaillant Group France](https://www.tamtam.ai/c/vaillant-group-france) (jobs.vaillant-group.com)
Development and manufacturing of heating and cooling systems focused on renewable energy, providing comfort and customized solutions in France. | Renewable Energy Equipment Manufacturing | 馃嚝馃嚪 Nantes | 205 | |
| 8 | [Knutsen LNG France](https://www.tamtam.ai/c/knutsen-lng-france) (knutsenoas.com)
A subsidiary of Knutsen OAS Shipping managing LNG carriers sailing under the RIF Flag with French officers from a French office | Maritime Transportation | 馃嚝馃嚪 Nantes | 165 | |
| 9 | [Leroux & Lotz Technologies (LLT)](https://www.tamtam.ai/c/leroux-and-lotz-technologies-llt) (lerouxlotz.com)
Design and manufacture of custom biomass boilers and combustion systems, including maintenance, refurbishment, and complete rebuild services. | Utility System Construction | 馃嚝馃嚪 Nantes | 149 | 1946 |
| 10 | [Territoire d'茅nergie Loire-Atlantique (TE44)](https://www.tamtam.ai/c/territoire-d-energie-loire-atlantique-te44) (te44.fr)
Manages public electricity and gas distribution networks, maintains street lighting, invests in renewable energy infrastructure, and operates electric vehicle charging stations. | Government Administration | 馃嚝馃嚪 Orvault | 92 | 1938 |
| 11 | [Dome Solar](https://www.tamtam.ai/c/dome-solar) (dome-solar.com)
French leader manufacturing high quality photovoltaic mounting systems for flat and sloped roofs across industrial, commercial, and agricultural sectors with certified technical assistance. | Renewable Energy Semiconductor Manufacturing | 馃嚝馃嚪 Rez茅 | 73 | 2008 |
| 12 | [Beem](https://www.tamtam.ai/c/beem-nantes) (beemenergy.fr)
Helping individuals take charge of their energy consumption and accelerate the transition to cleaner energy sources for homes | Solar Electric Power Generation | 馃嚝馃嚪 Nantes | 70 | 2018 |
| 13 | [SYSTOVI](https://www.tamtam.ai/c/systovi) (systovi.com)
Specializing in creating and producing cutting-edge BIPV systems that seamlessly integrate solar panels into building structures for energy generation | Solar Electric Power Generation | 馃嚝馃嚪 Carquefou | 54 | 2008 |
| 14 | [Sunology](https://www.tamtam.ai/c/sunology) (sunology.eu)
Provider of residential solar solutions including plug-and-play stations, smart custom roofs, modular batteries, and monitoring applications for home energy autonomy and savings. | Retail Appliances, Electrical, and Electronic Equipment | 馃嚝馃嚪 Saint-Herblain | 46 | 2019 |
| 15 | [Armor Battery Films](https://www.tamtam.ai/c/armor-battery-films) (armorbatteryfilms.com)
Specializing in enhancing lithium-ion battery performance, En' Safe庐 provides aluminum/copper foil coated with a conductive primer to improve anode/cathode interface for increased safety and longevity | Chemical Manufacturing | 馃嚝馃嚪 Nantes | 42 | 2015 |
| 16 | [DINTEC](https://www.tamtam.ai/c/dintec) (gokinell.com)
Family-owned company specializing in custom solutions for mobile machine manufacturers, combining expertise in electronics, hydraulics, and more to create innovative and high-quality projects | Machinery Manufacturing | 馃嚝馃嚪 Nantes | 42 | 2010 |
| 17 | [ALKA MARINE](https://www.tamtam.ai/c/alka-marine) (alkamarine.com)
A new player in renewable marine energy support, offering integrated solutions from design to maritime operations, owns a tugboat and a bathymetric vessel under the French flag | Maritime Transportation | 馃嚝馃嚪 Saint-Nazaire | 40 | 2020 |
| 18 | [GAROS ENERGIE](https://www.tamtam.ai/c/garos-energie) (garos-energie.fr)
Electrotechnical manufacturing company located in France specializing in energy solutions and electrical components | Electrical Equipment Manufacturing | 馃嚝馃嚪 Bouguenais | 39 | 1984 |
| 19 | [GeniWatt](https://www.tamtam.ai/c/geniwatt) (geniwatt.fr)
GeniWatt offers turnkey solutions for diesel and gas power plants, providing installation, commissioning, maintenance, and supply of certified replacement parts | Mechanical Or Industrial Engineering | 馃嚝馃嚪 La Chevroli猫re | 38 | 2011 |
| 20 | [PHOTOVOLT](https://www.tamtam.ai/c/photovolt) (photovolt.fr)
Photovolt specializes in designing and installing solar panels for residential and commercial clients, offering services from consultation to installation and maintenance | Renewable Energy Semiconductor Manufacturing | 馃嚝馃嚪 Thouar茅-sur-Loire | 38 | 2006 |
| 21 | [Libre Energie](https://www.tamtam.ai/c/libre-energie) (libre-energie.com)
Specializing in solar energy production since 2007, we aim to provide clean energy solutions for individuals and businesses with personalized and quality service | Solar Electric Power Generation | 馃嚝馃嚪 Les Sorini猫res | 37 | 2007 |
| 22 | [hestiia](https://www.tamtam.ai/c/hestiia) (go.hestiia.com)
Innovative company leveraging wasted heat from computers to create sustainable consumer products, driving the energy transition towards a greener future | Appliances, Electrical, and Electronics Manufacturing | 馃嚝馃嚪 Nantes | 26 | 2016 |
| 23 | [Be Green](https://www.tamtam.ai/c/be-green) (begreen-group.fr)
Design, manufacture, and install solar power plants, solar buildings, canopies, and charging stations with integrated expertise and comprehensive support. | Renewable Energy Equipment Manufacturing | 馃嚝馃嚪 Saint-Herblain | 25 | 2019 |
| 24 | [Enerdigit](https://www.tamtam.ai/c/enerdigit) (enerdigit.fr)
Electricity flexibility operator providing financial compensation for load shedding and developing large-scale battery storage projects to ensure grid security and energy transition. | Services for Renewable Energy | 馃嚝馃嚪 Nantes | 24 | 2015 |
| 25 | [GEPS Techno](https://www.tamtam.ai/c/geps-techno) (geps-techno.com)
Harvest ocean data, enable offshore communication networks, power subsea equipment with marine renewable energies, develop customized innovative solutions. | Services for Renewable Energy | 馃嚝馃嚪 Gu茅rande | 22 | 2011 |
| 26 | [SYCOMORE](https://www.tamtam.ai/c/sycomore) (keon-group.com)
Sycomore specializes in operating and maintaining agricultural and territorial biogas units, with a team of experienced multidisciplinary professionals #biomethane #biogas | Transportation, Logistics, Supply Chain and Storage | 馃嚝馃嚪 Bouguenais | 21 | 2014 |
| 27 | [PNE France](https://www.tamtam.ai/c/pne-france) (pne-france.fr)
Develops, builds, and operates wind and solar farms across metropolitan territory, integrating human and environmental stakes in renewable energy projects. | Renewable Energy Power Generation | 馃嚝馃嚪 Nantes | 20 | 2003 |
| 28 | [Hellospark 鈿★笍](https://www.tamtam.ai/c/hellospark) (hellospark.fr)
French company specializing in renewable energy and electric mobility, transforming unused spaces into solar energy centers with photovoltaic canopies to reduce carbon footprint | Renewable Energy Power Generation | 馃嚝馃嚪 Nantes | 18 | |
| 29 | [2G Energie France SAS](https://www.tamtam.ai/c/2g-energie-france-sas) (2-g.com)
Design and supply of turnkey biogas and natural gas cogeneration plants with patented engines, remote monitoring, and nationwide technical support in France. | Renewable Energy Semiconductor Manufacturing | 馃嚝馃嚪 Sainte-Luce-sur-Loire | 18 | 2016 |
| 30 | [NEOS SOLAIRE - Orvault](https://www.tamtam.ai/c/neos-solaire-orvault) (neos-solaire.fr)
NEOS specializes in tailored photovoltaic solutions for businesses, focusing on energy efficiency, financial optimization, and sustainability for a greener future | Services for Renewable Energy | 馃嚝馃嚪 Orvault | 18 | 2022 |
## 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 Nov 14, 2026.
## More company lists in the Loire-Atlantique department
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- [Companies with in-house R&D in the Loire-Atlantique department](https://www.tamtam.ai/l/r-and-d-companies-loire-atlantique) (207)
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- [Professional services firms in the Loire-Atlantique department](https://www.tamtam.ai/l/professional-services-firms-loire-atlantique) (158)
- [Software Development companies in the Loire-Atlantique department](https://www.tamtam.ai/l/software-development-companies-loire-atlantique) (137)
- [SaaS companies in the Loire-Atlantique department](https://www.tamtam.ai/l/saas-companies-loire-atlantique) (135)
- [IT services companies in the Loire-Atlantique department](https://www.tamtam.ai/l/it-services-companies-loire-atlantique) (130)
- [Manufacturers in the Loire-Atlantique department](https://www.tamtam.ai/l/manufacturers-loire-atlantique) (125)
- [IT Services and IT Consulting companies in the Loire-Atlantique department](https://www.tamtam.ai/l/it-services-and-it-consulting-companies-loire-atlantique) (110)
- [Consulting firms in the Loire-Atlantique department](https://www.tamtam.ai/l/consulting-firms-loire-atlantique) (94)
- [Distributors and wholesalers in the Loire-Atlantique department](https://www.tamtam.ai/l/distributors-and-wholesalers-loire-atlantique) (94)
- [Hardware manufacturers in the Loire-Atlantique department](https://www.tamtam.ai/l/hardware-companies-loire-atlantique) (86)
- [Business Consulting and Services companies in the Loire-Atlantique department](https://www.tamtam.ai/l/business-consulting-and-services-companies-loire-atlantique) (83)
- [Public sector organisations in the Loire-Atlantique department](https://www.tamtam.ai/l/public-sector-organisations-loire-atlantique) (80)
- [Family-owned companies in the Loire-Atlantique department](https://www.tamtam.ai/l/family-owned-companies-loire-atlantique) (71)
- [Education providers in the Loire-Atlantique department](https://www.tamtam.ai/l/education-companies-loire-atlantique) (68)
- [Real Estate companies in the Loire-Atlantique department](https://www.tamtam.ai/l/real-estate-companies-loire-atlantique) (67)
- [Financial services firms in the Loire-Atlantique department](https://www.tamtam.ai/l/financial-services-firms-loire-atlantique) (65)
- [Law Practice companies in the Loire-Atlantique department](https://www.tamtam.ai/l/law-practice-companies-loire-atlantique) (62)
- [Retail companies in the Loire-Atlantique department](https://www.tamtam.ai/l/retail-companies-loire-atlantique) (61)
- [Subscription businesses in the Loire-Atlantique department](https://www.tamtam.ai/l/subscription-businesses-loire-atlantique) (61)
- [Critical infrastructure operators in the Loire-Atlantique department](https://www.tamtam.ai/l/critical-infrastructure-operators-loire-atlantique) (58)
- [Events Services companies in the Loire-Atlantique department](https://www.tamtam.ai/l/events-services-companies-loire-atlantique) (58)
## The same list elsewhere in France
- [Energy companies in France](https://www.tamtam.ai/l/energy-companies-france) (1,594)
- [Energy companies in 脦le-de-France](https://www.tamtam.ai/l/energy-companies-ile-de-france) (475)
- [Energy companies in Auvergne-Rh么ne-Alpes](https://www.tamtam.ai/l/energy-companies-auvergne-rhone-alpes) (236)
- [Energy companies in Nouvelle-Aquitaine](https://www.tamtam.ai/l/energy-companies-nouvelle-aquitaine) (173)
- [Energy companies in the Hauts-de-Seine department](https://www.tamtam.ai/l/energy-companies-hauts-de-seine) (144)
- [Energy companies in Occitanie](https://www.tamtam.ai/l/energy-companies-occitanie) (128)
- [Energy companies in Provence-Alpes-C么te d'Azur](https://www.tamtam.ai/l/energy-companies-provence-alpes-cote-dazur) (124)
- [Energy companies in Grand Est](https://www.tamtam.ai/l/energy-companies-grand-est) (116)
- [Energy companies in the Rh么ne department](https://www.tamtam.ai/l/energy-companies-rhone) (104)
- [Energy companies in Hauts-de-France](https://www.tamtam.ai/l/energy-companies-hauts-de-france) (74)
- [Energy companies in Pays de la Loire](https://www.tamtam.ai/l/energy-companies-pays-de-la-loire) (66)
- [Energy companies in the Gironde department](https://www.tamtam.ai/l/energy-companies-gironde) (61)
- [Energy companies in the Bouches-du-Rh么ne department](https://www.tamtam.ai/l/energy-companies-bouches-du-rhone) (58)
- [Energy companies in Brittany](https://www.tamtam.ai/l/energy-companies-brittany) (56)
- [Energy companies in the Haute-Garonne department](https://www.tamtam.ai/l/energy-companies-haute-garonne) (48)
- [Energy companies in the Nord department](https://www.tamtam.ai/l/energy-companies-nord) (42)
- [Energy companies in the Is猫re department](https://www.tamtam.ai/l/energy-companies-isere) (41)
- [Energy companies in the H茅rault department](https://www.tamtam.ai/l/energy-companies-herault) (38)
- [Energy companies in Normandy](https://www.tamtam.ai/l/energy-companies-normandy) (38)
- [Energy companies in Bourgogne-Franche-Comt茅](https://www.tamtam.ai/l/energy-companies-bourgogne-franche-comte) (37)
- [Energy companies in the Bas-Rhin department](https://www.tamtam.ai/l/energy-companies-bas-rhin) (33)
- [Energy companies in Paris](https://www.tamtam.ai/l/energy-companies-paris) (187)
- [Energy companies in Lyon](https://www.tamtam.ai/l/energy-companies-lyon) (34)
- [Energy companies in Toulouse](https://www.tamtam.ai/l/energy-companies-toulouse) (33)
## The same list elsewhere
- [Energy companies in the world](https://www.tamtam.ai/l/energy-companies-in-the-world) (10,501)
- [Energy companies in Europe](https://www.tamtam.ai/l/energy-companies-in-europe) (4,235)
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Source: https://www.tamtam.ai/l/energy-companies-loire-atlantique