ABSTRACT
Two or three years after the oil shock in 1974, a small group of
Swiss scientists of various backgrounds and institutions (I was with
Laboratories RCA in Zu¨rich, a subsidiary of RCA corporation in the
US) gathered privately in order to discuss the question of how to
scope with the energy problem, in particular also whether solar
photovoltaics in Switzerland would be a route to go. However, first
a-Si cells, patented in 1977, had efficiencies in the range of less
than 1%, obviously too small to contribute in a sensible way to
the supply of electrical power. This would be certainly true for
countries where solar inputs are in the range of 1200 kWh/year, like
in Switzerland, or less. The fabrication of the first crystalline Si cells
and research goes back to the years between 1950 and 1960 induced
by the emerging satellite technology. Best small-sized laboratory
cells reached in the 1960s efficiencies of about 11%, which could be
improved to about 17% in the 1970s. However, cells could be only
produced at high cost. Cost was not a real problem for satellites, but
it would be crucial for terrestrial large area solar photovoltaics. So
some of us, including me, had doubts whether cell technology could
be improved and cost reduced to a degree that it might substantially
contribute to electrical energy supply. During these years I hadmany
discussions with A. Rose, at that time one of the world’s leading
scientist in photovoltaics and photoconductivity. He was convinced
that human ingenuity would overcome these problems and that the
abundant radiation of the sun to the earth could be tapped efficiently
and at reasonable cost. Would this become reality?