Solar energy is also known as photovoltaic systems which convert light energy into electricity. The term "photo" comes from the Greek "phos," meaning "light." "Volt" is named for Alessandro Volta (1745-1827), a pioneer in the study of electricity. "Photo-voltaics," then translates into "light-electricity."
Most commonly known as "solar cells," photovoltaic systems are already used in our day-to-day lives in small calculators, wrist watches and emergency 911 call boxes on highways.