Here's a timeline of key milestones:
* 1839: Alexandre Edmond Becquerel discovered the photovoltaic effect, the foundation of modern solar cells.
* 1873: Willoughby Smith discovered the photoconductivity of selenium, a material later used in early solar cells.
* 1883: Charles Fritts created the first practical solar cell using selenium.
* 1941: Russell Ohl, working at Bell Labs, discovered the junction effect in silicon, a critical component of modern solar cells.
* 1954: Bell Labs created the first practical silicon solar cell with an efficiency of 6%. This was a significant breakthrough, but the technology was too expensive for widespread use.
* 1958: The first solar-powered satellite was launched, demonstrating the potential of solar energy for space applications.
Therefore, you can't pin down a single year for the invention of solar power. It's a gradual development with many key discoveries and advancements over time.
