How Does Solar Power Work?

<p>This project covers the fundamentals of solar energy and how it is used to generate electricity! Here you will become familiar with the vocabulary, units, and instruments used in identifying and measuring solar energy.&nbsp;</p>

<h2><strong>Objectives</strong></h2>

<ul>
<li>Describe how energy from the sun is converted into electrical energy.</li>
<li>Construct an argument about using solar energy to mitigate the effects of climate change.</li>
<li>Evaluate the effectiveness of using solar panels to meet basic energy needs.<br />
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</ul>

<p>The U.S. Department of Energy and the National Community Solar Partnership (NCSP) are hoping to use solar energy to power the equivalent of five million households by 2025 and create $1 billion in energy bill savings. Furthermore, the National Renewable Energy Laboratory (NREL) projects solar energy could provide 45% of the electricity in the United States by 2050.&nbsp;</p>

<p>But why? What is solar power and why are countries all over the world racing to increase their use of it?</p>

<p><strong>Benefits&nbsp;of Renewable Energy</strong></p>

<p>● Reduces air pollution, thereby improving public health.<br />
● Reduces dependence on importing fuels from other countries.<br />
● Creates economic development and jobs in manufacturing, installation, and more.</p>

<p>Now you know why solar energy is useful. So how can we understand it and control it to do what we want?</p>

<p style="text-align:center;"><em>Bhadla Solar Park in India is the largest solar farm in the world. Image by Azure Power.</em></p>

<p>Solar energy is any type of energy generated by the sun.&nbsp;Solar energy&nbsp;warms the Earth, causes&nbsp;wind&nbsp;and&nbsp;weather, and sustains plant and animal life.&nbsp;You may have heard of photosynthesis, which is the process used by plants to convert the sun&rsquo;s energy into chemical energy (or food). However,&nbsp;<b>solar cells, or photovoltaic cells, convert solar energy into electricity.&nbsp;</b></p>

<p>Solar energy is the cleanest and most abundant&nbsp;<strong>renewable energy</strong>&nbsp;source available. This means solar energy is generated from natural resources and can be used over and over again without releasing carbon dioxide or other harmful fossil fuels into the air.</p>

<p>Solar energy is created by nuclear fusion that takes place in the sun. Fusion occurs when protons of hydrogen atoms violently collide in the sun&rsquo;s core and fuse to create a helium atom.</p>

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<blockquote>
<p><em>This proton-proton chain reaction emits an enormous amount of energy in the form of waves and particles.</em></p>
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<p>The energy, heat, and light from the sun flow away in the form of electromagnetic radiation (EMR). The diagram below shows the electromagnetic (EM) spectrum, which is the range of all types of EM radiation. The types of EM radiation can vary from the visible light that comes from a lamp in your house to the radio waves that come from a radio station to the harmful UV rays that can cause skin cancer.<br />
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<blockquote>
<p><em>The electromagnetic spectrum. Image by BRGFX on FREEPIK.</em></p>
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<p>There are different ways of capturing solar radiation and converting it into usable energy. The methods use either active solar energy or passive solar energy. Active solar technologies use electrical or mechanical devices to actively convert solar energy into another form of energy, most often heat or electricity. A popular example of this is a solar panel, which we will learn about on the next page. Passive solar technologies do not use any external devices. Instead, they take advantage of the local climate to heat structures during the winter, and reflect heat during the summer. An example of this is a solar oven or cooker, which uses sunlight to cook food. Check out the extension activity at the end to learn how to make one of these yourself!</p>