TNO, together with Dutch industrial partners Levitech, Tempress, Yparex and SMIT Thermal Solutions and the German R&D center of Hanwha Q Cells, has demonstrated for the first time that bifacial tandem solar technology can be manufactured at industrial scale, delivering measurably higher electricity output from the same surface area under real operating conditions.
The module architecture stacks monolithic perovskite/silicon solar cells to reach higher efficiencies than current silicon-only modules, while its bifacial design captures light from both the front and rear of the panel for additional yield. The work was carried out under the Fit4Market project, a Dutch-German collaboration TNO has coordinated since 2023, which set out to combine bifacial light capture with tandem cell architecture using processes compatible with existing photovoltaic production lines - prioritizing scalability and real-world validation over maximizing laboratory efficiency.
Testing shows the bifacial tandem approach delivers 15-30% higher power output than a conventional bifacial silicon module used as reference. The first energy yield measurements from an actual rooftop installation confirm an approximately 16% increase in annual electricity generation. A physical demonstrator is currently undergoing outdoor validation, and a second generation of prototypes is now on the roof gathering further data under real operating conditions - evidence, the team says, that the technology's advantages hold up outside the lab.
Valerio Zardett, Senior Scientist at TNO, said: "By focusing on industrial processes and bifacial design optimization, we show that higher power density is achievable in practice. This is a key step towards making bifacial tandem solar technology relevant for large-scale deployment."
The technology is aimed at two deployment scenarios: generating more electricity within a fixed footprint, or generating the same amount of electricity within a smaller footprint than conventional technology requires - making it relevant both for space-constrained urban and industrial rooftops and for utility-scale projects looking to reduce a solar farm's total land footprint. TNO recommends the technology for installations with an albedo of 10-20%, and notes the bifacial design can be further customized to match local site conditions and reflectivity.
The next phase of the project will focus on further scaling, longer-term outdoor validation, and continued collaboration with industry partners to prepare the technology for broader deployment. Fit4Market is supported through the Dutch Topsector Energy program.
