Solar Energy
 

Solar Power

Have you ever used a magnifying glass to make something melt or burn? You were using solar power!

Rooftop solar panels

“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!

Make your own solar oven

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.

View a photo of a home with solar panels

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.

Today, more than 10,000 American families get all of their electricity from solar power. And silicon from just one ton of sand, used in photovoltaic cells, could produce as much electricity as burning 500,000 tons of coal.

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.

Photovoltaic solar panel

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 – the panels cost a lot, and a lot of open land is needed.

View a photo of a solar power plant