Have you ever used a magnifying glass to make something melt or burn? You were using solar power!
“Solar” is the Latin word for “sun” and it’s a powerful source of energy. In fact, the sunlight that shines on the Earth in just one hour could meet world energy demand for an entire year!
We can use solar power in two different ways – as a heat source, and as an energy source.
People have used the sun as a heat source for thousands of years. Families in ancient Greece built their homes to get the most sunlight during the cold winter months. In the 1830s, explorer John Herschel used a solar collector to cook food during an adventure in Africa. You can even try this at home!
Today, we can use solar collectors for heating water and air in our homes. If you’ve seen a house with big shiny panels on the roof, that family is using solar power.
We can also use solar energy to make electricity. The process is called photovoltaics. If you have a solar-powered watch or calculator, you’re using photovoltaics!
In 1954, scientists at Bell Telephone discovered that silicon (an element found in sand) created an electric charge when it was exposed to lots of sunlight. Just a few years later, silicon chips were used to help power space satellites.
You might be wondering why we don’t use solar electricity all the time. Solar power systems make a different kind of electricity than big power plants do, so different wiring is needed and that can be expensive.
There are a few big solar power plants in the United States, mostly in California. It’s difficult and expensive to make a lot of electricity using photovoltaics because the panels cost are expensive, and a lot of open land is needed.