Green Technology: Solar Energy
The amount of sunlight that strikes the earth's surface in an hour and a half is enough to handle the entire world's energy consumption for a full year. Solar technologies convert sunlight into electrical energy either through photovoltaic (PV) panels or through mirrors that concentrate solar radiation. This energy can be used to generate electricity or be stored in batteries or thermal storage.
Below, you can find resources and information on the basics of solar radiation,photovoltaic and concentrating solar-thermal powertechnologies, electrical grid systems integration, and the non-hardware aspects (soft costs) of solar energy.You can also learn more about how to go solar and the solar energy industry. In addition, you can dive deeper into solar energy and learn about how the U.S. Department of Energy Solar Energy Technologies Office is driving innovative research and development in these areas.
Solar Energy 101
Solar radiation is light – also known as electromagnetic radiation – that is emitted by the sun. While every location on Earth receives some sunlight over a year, the amount of solar radiation that reaches any one spot on the Earth’s surface varies. Solar technologies capture this radiation and turn it into useful forms of energy. Learn about the basics of solar radiation.
Photovoltaics Basics
You're likely most familiar with PV, which is utilized in solar panels. When the sun shines onto a solar panel, energy from the sunlight is absorbed by the PV cells in the panel. This energy creates electrical charges that move in response to an internal electrical field in the cell, causing electricity to flow.
How does solar power work?Solar power works by converting energy from the sun into power. There are two forms of energy generated from the sun for our use – electricity and heat. Both are generated through the use of solar panels, which range in size from residential rooftops to ‘solar farms’ stretching over acres of rural land. |
How exactly is electricity from solar energy produced?Solar panels are usually made from silicon, or another semiconductor material installed in a metal panel frame with a glass casing. When this material is exposed to photons of sunlight (very small packets of energy) it releases electrons and produces an electric charge. This PV charge creates an electric current (specifically, direct current or DC), which is captured by the wiring in solar panels. This DC electricity is then converted to alternating current (AC) by an inverter. AC is the type of electrical current used when you plug appliances into normal wall sockets. |
Is solar power a clean energy source?Yes, solar power is a renewable and infinite energy source that creates no harmful greenhouse gas emissions – as long as the sun continues to shine, energy will be released. The carbon footprint of solar panels is already quite small, as they last for over 25 years. Plus, the materials used in the panels are increasingly recycled, so the carbon footprint will continue to shrink. |
What are solar farms?Solar farms, also known as solar parks or solar fields, are large areas of land containing interconnected solar panels positioned together over many acres, to harvest large amounts of solar energy at the same time. Solar farms are designed for large-scale solar energy generation that feed directly into the grid, as opposed to individual solar panels that usually power a single home or building. |
Reference: https://www.energy.gov/eere/solar/how-does-solar-work
https://www.nationalgrid.com/stories/energy-explained/how-does-solar-power-work