PHYSEE uses glass to make buildings smart and sustainable without compromising on the architectural design.

Based in Delft, PHYSEE is a Delft University of Technology spin-off from 2014 founded by Willem Kesteloo and Ferdinand Grapperhaus. Since then the tech company has successfully supplied various real estate projects, as the Rabobank head-office in Eindhoven and the Goede Doelen Loterij headquarters in Amsterdam, with their electricity- and data generating windows. PHYSEE won the Dutch start-up of the year award in 2014, Europe’s best energy start-up in 2015 and the World Postcode Lottery Green Challenge (EUR 500k) in 2016 and became World Economic Forum Technology Pioneer in 2017. As owner of a growing self-developed patent family and employer of 15+ engineers, the young tech company demonstrates that Research & Development can be exciting and with impact.


Molengraaffsingel 10
2629 JD Delft
The Netherlands

Ferdinand Grapperhaus
Willem Kesteloo