- Field data confirms efficiency and economic viability: The technology delivers high and reliable overall performance, even under highly demanding weather conditions and with tightly dimensioned systems. The field data shows that maximum output and optimal use of surface area can indeed be combined with Sunmaxx.
- Renewed quality label supported by real data: As part of the successful renewal of the Solar Keymark certification, Sunmaxx is publishing comprehensive data from its operational PVT systems for the first time. In scientific collaboration with the SPF Institute for Solar Technology, efficiency, system design, and annual performance of the PVT modules were analyzed in detail.
- Proven key technology for the heating transition: With high economic efficiency and confirmed system reliability, Sunmaxx positions itself as a technology partner for the decarbonization of heat supply and industrial processes.
Dresden, 10.04.2026: As a technology leader in the field of photovoltaic-thermal hybrid modules (PVT), Sunmaxx has once again successfully passed its Solar Keymark certification. This Europe-wide recognized label is considered a key quality benchmark for solar thermal systems and the leading certification for PVT systems. The renewal confirms the high performance, reliability, and compliance with standards of the hybrid modules manufactured in Saxony.
Sunmaxx places particular emphasis on transparency and real-world relevance. The published system data originates from actual projects in operation under real rooftop weather conditions. Rather than relying on idealized laboratory environments, the results demonstrate how PVT systems perform in everyday use: delivering heat and electricity efficiently and reliably for households, industry, and commerce. The data shows that Sunmaxx technology reaches its full performance potential under real conditions – especially when used as the sole heat source for brine-to-water heat pumps.
The measurements demonstrate that operating a brine-to-water heat pump with a smaller PVT system than the Sunmaxx-recommended standard of 4 m² per kW of heating output is feasible. The analyzed systems include installations with a reduced design of even only 2 m² PVT per kW of heating output. For a system commissioned in September 2025 with this configuration, efficiency values were measured in a single-family home during the cold winter of 2025/26. The building is equipped with underfloor heating and requires a flow temperature of 50°C for domestic hot water. The average ambient temperature in January was 2.5°C, with lows reaching -7.5°C. Despite these conditions, a coefficient of performance (COP) of 3.9 was achieved in that month. During transitional seasons, performance is significantly higher: in October, with an average temperature of around 11°C, a COP of 4.7 was recorded.
On an annual basis, performance figures are expected to be considerably higher, as the current data set primarily reflects the least favorable months of the heating season. By utilizing solar irradiation via a full-surface absorber, Sunmaxx PVT systems particularly benefit during transitional and summer months. The key advantage: two renewable energy sources are combined within a single module. This significantly increases supply reliability, even in low temperatures, snowfall, or limited solar radiation. At the same time, Sunmaxx’s patented industrial manufacturing process enables particularly attractive investment costs. The result is exceptionally high surface and resource efficiency, forming the basis for economical and largely self-sufficient energy systems.
The certification was conducted by the SPF Institute for Solar Technology. Dr. Wilhelm Stein, CEO of Sunmaxx, states: “The renewed Solar Keymark certification underlines our commitment to combining industrial scalability, high performance, and maximum system compatibility in a single technology. A successful heating transition requires solutions that are not only innovative but also reliable under real-world conditions – in both residential and industrial applications.”
With this successful recertification, Sunmaxx strengthens its position as a reliable partner for the decarbonization of buildings, industrial processes, and district heating networks. At the same time, the company establishes a key foundation for funding eligibility, investment security, and the accelerated market ramp-up of PVT systems as a core technology of the heating transition.
The field data report is available at sunmaxx-pvt.com/solution/downloads.
About Sunmaxx
Sunmaxx is a leading manufacturer of PVT modules. Headquartered in Ottendorf-Okrilla near Dresden, the company operates the world’s largest industrial-scale production facility for hybrid modules that combine photovoltaics and solar thermal energy in a single system. Sunmaxx’s innovative technological approach makes PVT a cost-effective alternative to conventional renewable heating systems and enables the full decarbonization of heat supply and industrial processes.
About the Solar Keymark
The Solar Keymark is a Europe-wide recognized quality label for solar thermal systems. It certifies independent product testing and compliance with relevant European standards in terms of performance, safety, and quality.
About t he SPF Institute for Solar Technology
Founded in 1981, the SPF Institute for Solar Technology is part of OST (Eastern Switzerland University of Applied Sciences in Rapperswil, Switzerland) and is one of Europe’s leading research institutions in renewable energy. Around 50 employees operate a broad-based research laboratory as well as an internationally accredited testing facility. The close integration of research, development, and independent testing makes SPF one of the key certification bodies for solar thermal systems and PVT technologies.