Stefan Roest - Eternal Sun

Stefan Roest is CTO and founder of Eternal Sun: a company developing high-end sunlight simulators to test solar panels. Founded in 2011 as a spin-off from TU Delft, and after a rollercoaster ride of several years and multiple stages of stable growth, they are now an established name in the industry. With more than 60 employees worldwide, spread across several facilities in America, China and Malaysia, they are now the market leader in the West.

As CTO, Stefan is responsible for all technology and ensures that the solutions developed in-house remain in line with what the market demands. In a relatively young market characterised by a pretty high rate of innovation, this brings new challenges every day. Jointly ensuring that the combination of a lot of power and capacity continue to go hand in hand with the high level of accuracy for which they are so well known worldwide. And because the electronics in these devices control both the lamps and the measurements, every 0.1% accuracy matters. A reliable partner for the production of their circuit boards is therefore highly desirable - and they found this in Cimar Electronics.

The first versions of Eternal Sun's Spire flasher machines -and thus also the first designs of the circuit boards- date back to 2010 and have been gradually further improved over the years. A design update was therefore one of the main wishes in 2019. For this, Stefan started looking for a partner 'on the right scale': with enough knowledge in-house and sufficient capacity, and with their business and processes in good order. Preferably larger in size than they were themselves, so they could learn from the processes and experience in the supply chain. Cimar was a good match for them here: in addition to the experience and reliability, they really liked the flexibility shown in order to move with the capacity demand from Eternal Sun. They also enjoyed the intensive process of mutual coordination when converting the THT electronics from 2010 to more modern SMT alternatives.

But above all, the possibility of tackling the content of the development process together feels like a bonus in the partnership. The comprehensive approach, to be able to check the feasibility and deliverability of the components right from the start of a new design, is a real plus. That three-stage rocket of approval, validation and immediate implementation ensures shorter lead times and delivery certainty; something that cannot be taken for granted, as the COVID period has taught us. Fortunately, they can also rely on Cimar Electronics' knowledge and experience in this respect. And those are precisely the things that make a partner, a reliable partner.