On April 15th, 2022, a longtime champion for green hydrogen left us. Dr. Hans Sandlaß had been campaigning for the use of regenerative energies since 1983 in the former East Germany. In 1990, he founded the energy engineering firm IEE Ingenieurbüro Energieeinsparung GmbH and was committed to the use of hydrogen at an early stage. Until the end, he fervently participated in the social and political discussion. Dr. Hans Sandlaß died in Berlin at 90 years of age.