The recent hikes in gasoline price remind the public of the urgency to develop renewable energy sources and relieve ourselves from our addiction to oil. Solar energy is the most abundant renewable energy source and the ultimate source for many other forms of renewable energy: wind, hydropower, and biomass. The current technology provides means to convert solar energy into electricity (photovoltaics), chemical fuels (photosynthesis), and heat. This talk will explain in laymen terms how a photovoltaic solar cell works.