ABSTRACT
When I received from my parents books as a young teenager, they
were usually about nature, science, and technology. One of them
caught my attention, “Du und die Natur”, and it had a chapter about
solar energy. It stayed with me for decades to come. It became
clear to me that in order to harvest the sun’s energy, one needs
to understand much more about how sunlight can be changed
into “something useful,” beyond just heating. I had early in my
teenage years my own chemistry and electronics laboratory, and I
experimented a lot. There were also a few Se-photocells that gave
me an idea. However, I learned that I needed a lot of these cells to
even power one lamp. They had a mere 1% conversion efficiency
and I could not figure out what was done with the rest of 99% of the
energy.
