Celloraa Energy and ISC Konstanz Partner to Scale 1.2 GW TOPCon Production in India, Then Move to Back-Contact

A memorandum of understanding signed between a German research institute and an Indian solar manufacturer will shape how a new cell production site in Surat, Gujarat, comes online. The International Solar Energy Research Center (ISC) Konstanz announced the partnership with Celloraa Energy on the day of publication, March 5, 2026. The aim is to support a ramp-up of 1.2 GW of next-generation n-type solar cell capacity.

Under the agreement, ISC Konstanz becomes the primary technology and qualification partner for Celloraa's new high-volume manufacturing lines. The lines are built around TOPCon technology, and the project's stated goal is a 1.2 GW production base engineered for efficiency and yield. The announcement says the plan relies on German manufacturing equipment, which it describes as high quality and low in operating costs.

ISC Konstanz describes itself as a leading global institute for applied photovoltaic research. Its co-founder and director, Dr. Radovan Kopecek, framed the deal as part of the institute's mission to bridge the gap between cutting-edge research and industrial scale. He said that combining ISC Konstanz's expertise in n-type cell architecture with German equipment and Celloraa's manufacturing capability would create a blueprint for high-volume production of what he called the most efficient and reliable PV technology on the market.

The agreement is not limited to getting TOPCon lines running. It includes a comprehensive training program for Celloraa's team, to be delivered by ISC Konstanz staff, with the stated purpose of transferring knowledge and supporting operational excellence.

The partners will also jointly set out a research and development roadmap for next-generation device architectures. The sequence is specific: once the 1.2 GW TOPCon lines have stabilized, the collaboration will turn to co-developing high-efficiency, low-cost back-contact (BC) technology. According to the announcement, this would position Celloraa to move to tandem-ready BC structures and stay competitive over the long term.

Brijesh Gondaliya, a director of Celloraa Energy, said that bringing top-efficiency PV to market at scale takes more than buying equipment. It takes a partner who understands both the physics of the device and the economics of making it. He said ISC Konstanz's track record in piloting new technologies gives Celloraa confidence to move quickly from gigawatt-scale TOPCon into the next generation of BC devices, while pushing down the levelized cost of energy.

The announcement closes with broader ambitions: by deploying German-engineered production solutions and European R&D expertise, the partners say they want to set a new benchmark for power density and reliability. No financial terms, timeline for the ramp-up, or start date for the back-contact work are given. What to watch is whether the TOPCon lines reach stable production, since the back-contact phase is explicitly conditioned on that.