A Swiss scientist by the name of Horace de Saussure designed and built the first solar collector in 1767. Well that certainly goes back some time and looks at who was harnessing the sun's energy, but he did not turn the sun's energy into electricity.
A young 19 year old scientist had that privilege by the name of Edmund Becquerel in 1839. He had turned energy from the sun into electricity, known as the "photovoltaic effect". Not that it was a bad thing but it was very inefficient and not very practical for the time. Therefore, like so many other great discoveries it sat idle for many years.
