ConverLight® Sets New Benchmark for Schools

Balancing daylight, view, and thermal comfort has long been a challenge in school design. Across Europe, institutions are also under pressure to cut carbon emissions and meet ambitious energy targets without sacrificing the quality of their learning environments. A new Danish study shows that ConverLight dynamic glazing can deliver on all three fronts – outperforming both traditional and competitive electrochromic solar-control solutions.

When Prins Henry School in Copenhagen planned its campus expansion in 2022, architects faced a familiar challenge – how to create classrooms that are both bright and comfortable while meeting strict Danish sustainability targets. The solution was ConverLight® dynamic glass from ChromoGenics, with more than 1,100 square metres of adaptive façade glazing deployed across the school.

But how did it perform in practice? And how does it compare to other solar-control alternatives? To evaluate the effectiveness of various solar-control strategies, a comparative study was conducted by Associate Professor Christian A. Hviid.

In early 2025, one year after Prins Henry School was completed, a comparative study examined how five different façade and cooling strategies perform under real classroom conditions:

— Standard triple glazing with split-unit cooling
— Solar-coated glass with night ventilation and central cooling
— ConverLight® electrochromic glazing with night ventilation, but not active cooling
— A leading competitor in electrochromic glazing with night ventilation, but no active cooling
— External screens with night ventilation, but no active cooling

The aim was to determine which solutions best meet the demanding requirements of modern school buildings while supporting a healthy and productive indoor environment. Using IDA ICE building simulations, the study evaluated four key aspects: thermal comfort, cooling energy demand, daylight availability, and total CO₂ emissions, including both embodied and operational carbon.

Large glazed areas are both an advantage and a challenge. They offer generous daylight and a strong visual connection to the outdoors, yet they can also lead to overheating in summer and cold draughts in winter, increasing energy consumption. ConverLight addresses this by automatically adjusting to sunlight, maintaining visual comfort while limiting heat gain and reducing the need for active cooling.

According to the study, classrooms fitted with ConverLight stayed within EN 16798-1:2019 Category II comfort limits even during warm periods. Because the glass prevented overheating on its own, air conditioning could be eliminated. This, in turn, simplified the HVAC design, reduced ductwork, allowed for higher ceilings, and lowered overall energy use.

From an engineering perspective, ConverLight achieves a rare balance of thermal comfort, simplicity, and low lifecycle cost – all crucial factors for public buildings and schools with tight maintenance budgets.

Daylight and view are vital for focus, well-being and cognitive performance. Yet many classrooms rely on blinds or heavily tinted coatings that block sunlight completely, leaving spaces dim and uninspiring during the brightest hours of the day.

The study found that ConverLight achieved 86% daylight autonomy (sDA300,50%), well above the EN 17037 minimum of 50%. The glazing kept interiors bright and connected to the outdoors while filtering excess heat, ensuring comfortable light throughout the day. For students and teachers, this means calm, inspiring classrooms without rattle or constant blind adjustments.

The study also compared total CO₂ emissions, factoring in both embodied and operational carbon. ConverLight recorded the lowest total footprint among all tested façade types at just 2.4 kg CO₂e/m².

By removing the need for mechanical cooling and reducing reliance on artificial lighting, the technology delivers significant energy savings. Even the embodied carbon of the glazing system, roughly 85 kg CO₂e/m² for a triple-pane IGU, remains moderate compared with other advanced façades, especially given its long service life.

For property owners and municipalities, this helps ensure compliance with Danish BR29 regulations, EU taxonomy thresholds, and future EPD-based frameworks, all without compromising architectural design or usability.

Most solar-control systems come with trade-offs, where improved thermal comfort often means less daylight or a less attractive façade. ConverLight avoids those compromises by dynamically adjusting both Visible Light Transmittance (Tv ≈ 0.61 → 0.32) and solar factor (g ≈ 0.35 → 0.18) in real time. (G-values as low as 0.08 are possible if required by the project.)

With no external screens, motors or moving parts, the system integrates directly into standard IGU production and requires no maintenance. The result is a seamless façade that performs quietly and continuously throughout the year.

“The results show that electrochromic glazing solutions can perform exceptionally well across all performance criteria. They maintain thermal comfort without active cooling while preserving sufficient daylight levels, a balance that is difficult to achieve with most conventional shading systems” says Associate Professor Christian A. Hviid, Department of Civil and Mechanical Engineering, Technical University of Denmark.

For architects and engineers, ConverLight provides a proven path to combine energy performance with occupant wellbeing. For municipalities and developers, it offers a way to cut complexity, operational costs and carbon emissions while enhancing indoor quality.

“Dynamic glass isn’t just about energy efficiency. It’s about creating classrooms where students and teachers can perform at their best. ConverLight lets architects design bright, comfortable spaces that actively support learning, reduce energy use, and help schools meet both ambitious climate and academic goals – a true win-win-win” says Fredrik Fränding, CEO of ChromoGenics

As public buildings across Europe undergo renovation to meet stricter energy codes, the Danish results show what’s possible when daylight and sustainability are designed to work together. With proven performance, measurable savings and improved comfort, ConverLight sets a new standard for climate-smart, daylight-driven school design – and it’s ready to deliver today.