Energy from the Sun

Watch the following video about how humans are learning to use the Sun’s energy as a renewable resource. Jot down any questions you think of while you are watching.

Video Source: YouTube | Energy 101: Solar Power

View Transcript

Hi, I'm Lee Patrick Sullivan with Energy Now, and today I'd like to talk to you about the power of the Sun. Solar power is the most abundant most renewable resource we have. If we could collect

1/100, or 1%, of the sun's energy reaching the earth, it would be more energy than all humans use today. Just outside Yuma, Arizona is the sunniest place in the world. Ninety percent of the year the skies are clear, and these Southwest deserts have enough suitable land to supply eighty percent of the entire planets current use. The Sun has produced energy for billions of years and naturally energizes all of the plants on the planet. These plants give energy to animals and power the human body. This is done by a process called photosynthesis. For decades now, scientists have unlocked the secrets of how a plant creates energy through photosynthesis and can duplicate that process using modern technology in silicon. This process of creating electricity from the Sun can power our homes and cities. There are two ways of capturing the power of the Sun. First, is a photovoltaic device more commonly known as solar cells. They change sunlight directly into electricity. These individual cells are joined together to make solar panels. These can be placed on rooftops, in calculators, and even on large-scale fields covering many acres to power cities. Solar energy systems produce no air pollutants or carbon dioxide, and because they can be placed on the top of existing buildings, they do not require extra land for power plants. Another way to capture the sun's energy is by capturing its heat. Solar thermal electric power plants generate electricity by concentrating solar energy to boil water, which then produces steam. This steam turns a turbine, which moves a generator to produce electricity. Solar thermal electric plants consist of fields of mirrors to reflect the concentrated sunlight onto a receiver. The receiver then collects the solar energy and converts it to heat. The production of energy from solar thermal plants work essentially the same as fossil fuel power plants, but instead of producing steam from burning fossil fuels, the steam is made by the Sun. The only downside to this source of technology is that the power only exists as long as the Sun is up. To help solve this problem other forms of solar technology have been explored scientists are currently working on methods to store this energy for cloudy days and nighttime. One way to conquer this problem is building new power plants that combine a multitude of renewable energy sources. Using solar power, wind power, and biogas could do this. When one method is not creating electricity, the other could take over. Other methods such as storing excess power and batteries could also be a possible future for solar technology.

What do you think?

  • What questions did you think of while you were watching the video?
  • Find a partner and discuss two of your questions with them. See if you can come up with an answer. An educated guess is ok too.
  • Then, let your partner share two of their questions with you.