Shining a Light on Solar Panels
Using solar energy to power your home can be a great way to both help fight climate change and save money by lowering your electric bill.
An energy source for decades, solar panels can be found on residential and commercial rooftops, city and county roadside signs, in stadiums and on spacecrafts. Solar panels work by taking the sun’s energy and changing it into electricity. Comprised of many individual cells typically made from silicon (a semiconductor most commonly known for its use in computers), the silicon cells, when exposed to sunlight, generate electricity in a process known as the “photovoltaic effect.”
We’ve been experimenting with the photovoltaic process for almost two centuries. The photovoltaic effect—first documented by French physicist Edmond Becquerel in 1839—is the generation of voltage and electric current in a material upon exposure to solar radiation. In most photovoltaic usages the radiation is sunlight and the devices are called solar cells. The sun is basically a nuclear reactor. It releases small bits of energy called photons. These photons then travel 93 million miles from the sun to Earth in under 9 minutes. The sun emits enough photons in one hour to generate enough power to meet current global energy requirements for an entire year. I’d say that’s a great resource.
To harness that resource for our home, a collection of solar panels are installed on the roof. The solar cells absorb the energy from the sunlight and electrons begin to flow and generate an electric current. Electrical wires capture the current from each panel and combine it with the current from the other panels. This initial current is DC, direct current. Since all of the appliances, lights and equipment in our home use AC alternating current to operate, a device called a solar inverter is used to convert the DC current to AC current. The wires then take the collected DC current to the inverter and additional wires take the AC current out of the inverter and into our electrical panel to power our home. If our home produces more power than we need, the surplus energy gets sent back to the power grid and we get credit on our bill. This process of giving power back is called Net Metering.
If you’re interested in adding solar power to your home for cleaner energy and financial benefit, it is recommended that you do some research and consider all of your options. Contacting your power company, getting quotes from multiple installers, and talking with you neighbors, especially those who have installed solar panels, are a few of the things you can do. Good luck and keep your sunny side up!
—Leslie Chew, Force For Good Technical Advisor