It's tricky to pinpoint a single moment when scientists "found out" about solar energy. The understanding of solar energy has developed over centuries, with key discoveries and advancements throughout history. Here's a timeline to illustrate the process:

* Ancient Times: People observed the power of the sun for warmth, drying crops, and even using magnifying glasses to start fires.

* 1839: Edmond Becquerel discovered the photovoltaic effect, the principle behind solar panels. He observed that shining light on certain materials created an electric current.

* 1873: Willoughby Smith discovered the photoconductivity of selenium, paving the way for practical applications of solar energy.

* 1905: Albert Einstein's theory of the photoelectric effect explained how light interacts with matter to create electricity, solidifying the scientific understanding of solar energy.

* 1954: Bell Laboratories developed the first practical silicon solar cell, marking a significant milestone in solar technology.

* 1970s: The oil crisis sparked research and development in alternative energy sources, including solar energy.

* Present: Ongoing research focuses on improving the efficiency, affordability, and scalability of solar technologies.

So, rather than a single discovery, our understanding of solar energy evolved through a combination of observations, experiments, and technological breakthroughs.