Bolster acquires majority share in Eternal Sun
Bolster Investment Partners has acquired an 80% share in Eternal Sun, which makes sunlight. The company develops, produces and installs advanced testing equipment for solar panels and is the market leader worldwide in steady-state solar simulators for long-term and precise testing of solar panels. Its technology is essential for developers working on a new generation of solar panel technology, such as perovskite. Bolster will support the company in achieving international growth and further professionalization.
Eternal Sun embarks on its next growth phase with Bolster Investment Partners
Eternal Sun is taking the next step toward achieving its aims for growth. With the support of Bolster Investment Partners, the company is focusing on further product development, autonomous and acquisitive international expansion, and professionalization.
Eternal Sun was founded in 2011 by Stefan Roest, who developed his passion for solar energy as leader of the winning Nuon Solar Team at Delft University of Technology. Since its launch, the company has experienced impressive growth and supplies its test equipment to the most prominent solar panel producers and R&D laboratories in more than 60 countries. With its know-how and innovative strength, Eternal Sun is the global expert in the field of solar simulators. Eternal Sun’s high-quality test equipment is crucial for establishing the exact output, which forms the basis for determining the price of a solar panel. With another area of its technology, the company helps develop new solar panel technology and supplies leading producers and R&D institutes that are launching perovskite technology. In doing so, Eternal Sun is making a significant contribution to technological developments and value creation in the solar energy sector. In addition to test equipment, Eternal Sun also offers quality inspection services – import tests and factory inspections – for major solar panel importers and project developers.
The company excels through its expertise in flash simulators, which measure the maximum energy output of a solar panel by means of a flash of light, and steady-state simulators, which measure the long-term performance of panels. With a strong focus on innovation and customization, Eternal Sun responds flexibly to technological developments and changing test requirements. This puts Eternal Sun in an outstanding position to profit from further growth in the sector and new technological developments in the market.
Following a successful start-up phase and strategic takeovers, including the acquisition of U.S. firm Spire Solar in 2016 and China’s SunChine in 2022, Eternal Sun is ready for the next growth phase. The collaboration with Bolster Investment Partners marks a key step in the company’s further development.
Bolster not only provides financial clout, but also strategic support to help Eternal Sun achieve its ambitions for growth. Eternal Sun’s management team was searching for a partner for the long haul, which would provide support with buy-and-build projects and the company’s further internationalization and professionalization. Bolster’s long-term philosophy and expertise are a perfect fit for Eternal Sun’s sustainable and technological focus.
With this strategic partnership, Eternal Sun is taking a new step in its mission to take the solar energy sector further, by ensuring the highest measurement quality and the best test equipment.
Florian van Rijn van Alkemade, CEO of Eternal Sun: “Bolster is a perfect fit for our company’s next phase. With our first investors, Vermec and ABN AMRO Sustainable Impact Fund, we grew as a scale-up, and with Bolster we now have an investor on board who specializes in growing mid-size companies. We’re proud of our growth path over recent years. Market conditions are not always easy, but we have nevertheless shown uninterrupted growth.”
“That proves that we’ve expanded our company in the right direction strategically,” adds Erik Bentschap Knook, the company’s CCO, “but it also shows how we team up with our largest clients.”
Stefan Roest, CTO and founder, agrees proudly: “We play in the champions league of solar; our clients are the most prestigious developers of solar panels worldwide. We work with our largest clients on their technology roadmap. Our precise sunlight enables them to develop new technology better and faster. With the shift in solar to perovskite technology, I see a really wonderful future for our company!”
Mark van Rijn, Managing Partner at Bolster, says: “We’re very happy with this new partnership. There are several catalysts for growth in the market for testing solar panels, for example, new technological developments such as perovskite and politically strategic self-sufficiency in energy generation. The worldwide leading position of Eternal Sun in the necessary test equipment, combined with its level of knowledge and innovative strength, give it a unique starting position. The organization is also led by a strong and broad-based team. We’re therefore looking forward with pleasure and enthusiasm to our collaboration!”
For more information, please contact:
Eternal Sun
Florian van Rijn van Alkemade: +31 (0) 6 30 93 61 44
Bolster Investment Partners
Mark van Rijn: +31 (0) 20 226 30 88
About Eternal Sun
Eternal Sun is a prominent player in the world of solar energy. The company specializes in developing, producing and installing advanced test equipment for solar panels. With innovative flash and steady-state solar simulators, Eternal Sun helps clients around the world in testing the performance and reliability of solar panels.
The company serves a wide range of clients, including solar panel manufacturers, independent laboratories and solar farm developers. With a global reach, being active in more than 60 countries and operating from six locations in four countries, Eternal Sun continues to grow. Thanks to in-depth expertise, technological innovation and a strong international presence, Eternal Sun continues to set the standard for solar energy test equipment.