Global leader in advanced solar panel testing equipment secures growth partner
Deal Flash
Bolster Investment Partners, a Netherlands-based investment firm, has acquired a majority stake in Eternal Sun, a global technology leader in advanced solar panel testing equipment, from ABN AMRO Sustainable Impact Fund, a private impact fund based in the Netherlands, and Vermec, a Belgium-based investment firm.
Bolster Investment Partners is a long-term investment firm focused on partnering with founder-led and family-owned businesses through both minority and majority stakes. The firm’s long-term approach and experience align well with sustainable and technology-driven businesses such as Eternal Sun.
Founded in 2011 by Stefan Roest, Eternal Sun develops, manufactures and installs advanced testing equipment for solar panels. With a focus on innovative flash and steady-state simulators, the company helps customers around the world assess the performance and reliability of solar panels.
The company serves leading solar panel manufacturers and independent laboratories across 60 countries, operating from six locations in four countries. Its high-precision testing equipment plays a vital role in quality control, pricing and R&D. In addition, Eternal Sun provides import testing and factory inspection services to major importers and developers of solar energy projects. Following earlier strategic acquisitions, such as Spire Solar in the USA and SunChine in China, the company is well positioned to benefit from continued market growth and technological advancements.
Playing in the Champions League of solar technology means constantly pushing the edge in performance, precision and the partners you choose. Oaklins proved to be exactly that: a sharp, trusted advisor who brought clarity, energy and sector expertise to the table. Their support helped us secure a long-term partner aligned with our global ambitions.STEFAN ROEST, FOUNDER AND CTO, ETERNAL SUN, THE NETHERLANDS
Oaklins' global reach helped find the right partner
Oaklins’ team in the Netherlands acted as the exclusive sell-side advisor to the shareholders of Eternal Sun on this transaction, while the team in Germany provided support in the early stages of the sale process. The deal highlights Oaklins’ extensive expertise in the energy and sustainability sector, and in advising both management and private equity investors on value maximization strategies for industry-leading businesses.
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