The companies listed in Oslo are predominantly involved in energy, including traditional oil and gas, and a significant cluster of renewable energy and related services. While some are large established entities, there's also a presence of more recently founded companies. Norsk Hydro specializes in sustainable industries like aluminium and renewable energy, while Statkraft is a global leader in renewable energy generation. BW Offshore engineers and operates floating production storage and offloading vessels, and Scatec ASA provides renewable energy solutions in emerging markets.
A notable pattern among these companies is their strong focus on energy generation, transmission, and associated infrastructure. There is a clear mix of long-standing companies, such as Norsk Hydro (founded 1905) and Statkraft (founded 1895), alongside newer players like Scatec ASA (founded 2007) and Norske Skog (founded 2017), indicating a blend of heritage and more recent development in the sector.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Norsk Hydrohydro.com
Development of sustainable industries including aluminium production, energy, metal recycling, renewables, and batteries with global operations and innovation focus. |
13,192 | |||
| 2 |
Reitan Retailreitanretail.no
A leading retail company in the Nordic and Baltic region operating discount grocery, convenience stores, and sustainable mobility solutions with over 3,800 outlets |
7,293 | |||
| 3 |
Statkraftstatkraft.com
A global leader in renewable energy generation, specializing in hydropower, wind power, solar power, and gas-fired power, with operations in 21 countries |
4,563 | |||
| 4 |
Statnett SF
The company operates the main power grid in Norway, transmitting electricity between regions and countries while developing and maintaining the network for future energy demands |
2,018 | |||
| 5 |
BW Offshorebwoffshore.com
Engineering and operating floating production storage and offloading vessels, providing tailored offshore energy solutions for global markets. |
1,943 | |||
| 6 |
DeepOceandeepoceangroup.com
Integrated provider of safe, high-quality subsea services and technologies for the offshore industry, focusing on survey, installation, maintenance, and project management globally |
1,800 | |||
| 7 | 1,678 | ||||
| 8 |
Scatec ASAscatec.com
Leading renewable energy solutions provider in emerging markets, developing, building, owning, and operating clean energy plants globally with over 46 GW capacity |
1,412 | |||
| 9 |
AF Gruppenafgruppen.no
A company focused on solving important societal issues, challenging the status quo, and creating new solutions for the future |
1,288 | |||
| 10 |
Seaway7seaway7.com
A global leader in delivering fixed offshore wind projects, dedicated to creating an efficient and sustainable energy supply for the future |
1,266 | |||
| 11 |
Hafslundhafslund.no
One of Norway's leading energy producers focusing on hydropower, system services, wholesale power trading, and innovative electrification projects for a cleaner environment |
957 | |||
| 12 |
Norske Skognorskeskog.com
Production of bio-products and packaging materials, operating profitable mills, focusing on bio energy, composites, chemicals, and publication paper. |
835 | |||
| 13 | 774 | ||||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 14 | 605 | ||||
| 15 |
BW LNGbw-group.com
Global leader in floating gas infrastructure solutions, developing, owning, and operating LNG carriers and floating storage and regasification units for sustainable growth |
482 | |||
| 16 | 453 | ||||
| 17 |
Infratekvinci-energies.no
Specializing in power supply, we ensure security and efficiency from design through maintenance and operation with a global network of committed employees |
439 | |||
| 18 |
Cool Company Ltd (CoolCo)coolcoltd.com
The company specializes in transporting clean natural gas as liquefied natural gas on a fleet of modern carriers |
384 | |||
| 19 |
Nel Hydrogennelhydrogen.com
A hydrogen company listed on the Oslo Stock Exchange, specializing in hydrogen production plants, fueling stations, and power-to-gas solutions for various industries |
323 | |||
| 20 |
Nord Poolnordpoolgroup.com
Europe's leading power market offering efficient trading, clearing, and settlement services across multiple countries, with 30 years of experience in the industry |
186 | |||
| 21 |
Frontline Management ASfrontlineplc.cy
A management company overseeing a Cyprus-based oil tanker company with one of the world's largest fleets, specializing in international crude oil transportation on major stock exchanges |
183 | |||
| 22 |
Vow ASAvowasa.com
A company and its subsidiaries specialize in converting biomass and waste into clean energy and valuable resources, promoting industry decarbonization and material recovery |
106 | |||
| 23 |
Hystarhystar.com
Specializing in advanced PEM electrolysers, the company focuses on large-scale green hydrogen production to reduce greenhouse gas emissions and tackle energy challenges |
64 | |||
| 24 |
Atlantic Marine Servicesdvergsten.com
The company is an offshore support service contractor providing accommodation rigs and drilling rigs to major operators in the oil and gas industry worldwide |
63 | |||
| 25 |
Yinson Renewablesyinson-renewables.com
Global independent renewable power producer with assets across the entire renewables value chain in Latin America, Europe, and Asia Pacific. |
46 | |||
| 26 |
Hydro Havrandhydro.com
The company specializes in using green hydrogen to replace fossil fuels in heavy industries, maritime sector, and long-distance transport to reduce global CO2 emissions |
6 | |||
| 27 |
Hydrogen Sourcehydrogen-source.com
A company focused on converting depleted gas fields into clean hydrogen storage sites, providing the world with clean and cheap hydrogen |
4 | |||
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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 Nov 11, 2026.
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