small is beautiful


JOKER Tech is a start-up company founded by Henk Oldenkamp and Julian Mattheis. Our mission is to enable true AC Photovoltaic modules.


Henk Oldenkamp

CTO – The Brain

1984 Founder of OKE services

1992 first µ-inverter

1997 License to NKF

2001 Pioneer in LED lighting and power electronics

2009 Consultant for SMA

2015 Finalist Google‘slittle box“ inverter

Julian Mattheis

CEO – The Entrepreneur

2006 Product manager at Q-Cells SE

2009 Founder of Solsol (PV factories)

2015 Founder of FleX-EV (battery swapping)

2019 Founder of PowerHouse Energy (EPC)