He has over 30 years of experience in the field of photovoltaics, ranging from thin film silicon and III-V solar cell experimental and modeling development and testing to solar cell processing development, outdoor and indoor performance of solar cells, policy and cost development. His current activities focus on employing spectrum conversion (down/up conversion) using nanocrystals to increase solar cell conversion efficiency for next-generation photovoltaic energy converters as well as performance analysis of (BI)PV systems in the field, in particular linked to the development of smart grid systems in the built environment.