Solar PV technology veteran and the 2016 winner of the prestigious Becquerel Prize, Prof. Christophe Ballif, is passing on the baton of the Swiss Center for Electronics and Microtechnology (CSEM) to another solar innovation leader, Tonio Buonassisi.  

A Professor of Mechanical Engineering at the Massachusetts Institute of Technology (MIT), Buonassisi brings his experience in solar innovation, AI-driven materials research, and sustainable technologies to the institute. Notable among his works is his contribution to integrating PV into emerging applications – from off-grid desalination to Internet of Things (IoT). 

According to the CSEM, Buonassisi is known for using AI to speed up the development of next-generation energy materials and has received top awards like the Presidential Early Career Award for Scientists and Engineers (PECASE) and the NSF CAREER Award. Till recently, he served as the founding director of a US Department of Energy initiative called ADDEPT, which works to advance durable perovskite-silicon tandem solar modules. 

On January 1, 2026, he will take over as the VP of Sustainable Energy at CSEM from Ballif, who will remain on board as scientific advisor. Ballif joined CSEM in 2013 and is credited with founding the PV division as a combined unit of EPFL’s PV Lab and CSEM’s activities.  

Ballif expanded his group to over 90 researchers and worked with more than 40 industry partners to advance solar, energy storage, and digital solutions. His tenure at CSEM saw major milestones such as the launch of a pilot line for heterojunction (HJT) solar cells, record perovskite-silicon tandem efficiency, and innovations including colored modules, ultra-light cells for stratospheric flights, solar-powered connected watches (Tissot), and PV tiles for historic buildings. He remains a key voice shaping Switzerland’s scientific and energy policy.  

“Tonio’s expertise in AI and photovoltaics will build on the exceptional foundation laid by Christophe Ballif whose visionary leadership has shaped CSEM’s global impact. This transition strengthens our commitment to driving sustainable innovation,” said CSEM CEO Alexandre Pauchard.