We’ve all seen solar arrays, but what exactly happens when light from the sun comes in contact with a solar panel? Let’s review the key components that make up your system and how it all works.
An array is a collection of solar panels comprised of “cells” which harvest the sun’s energy. When a photon from the sun hits a cell, it knocks loose an electron from the silicon atoms that make up the cell. The electrons are collected by the wires connected to the solar cell and wha-la, power! These wires are connected to other cells to make up a solar panel. One panel is connected to the next in a series of parallel connections known as a “string.” Your array is made up of one or more of these strings.
Your array wiring comes down from the roof in one or more conduits to an inverter. The inverter is usually located on a wall near your main service panel and converts the DC electricity of the solar array to AC electricity so it can be used in your house. In most cases it also has an display that allows you to read data about how your system is performing at a given moment and over time. Some systems use micro-inverters, which mount under the solar panels and allow AC electricity to be sent directly from the array.
The electricity flows from the inverter, through more wiring and conduit, to your main service panel. In most cases, we install a solar breaker at the bottom of your main service panel (aka electrical panel or breaker panel). This connection to your service panel is what makes it possible to power your home with solar. The solar electricity flows first to any loads running in the house, such as a refrigerator, TV, lights, or anything else that might be consuming power while the sun is shining.
If you have excess power being produced, the electricity is pushed out to the world at large through your net meter. A net meter is also considered your “Utility Billing Meter.” Here in Washington and Oregon, your utility allows you to spin your net meter backwards and generate a credit on your electric bill for your excess solar power (cha-ching!). These credits tend to build up quickly in the summer months and can be cashed-in during the less-sunny winter months.
With your own personal device, be it a laptop or mobile phone, you will have the ability to collect data from the inverter and present it visually through charts, graphs, or other animations. Most monitoring systems also allow you to view your data online, and some even track the overall energy use within the home. Monitoring systems illustrate the efficiency of your solar equipment and how it performs under various conditions.
Battery storage systems provide peace of mind by providing a clean, reliable, and affordable way to keep the lights on during power outages caused by storms or earthquakes. Solar PV systems are designed to shut down during outages to protect utility workers, but storage systems allow buildings to stay powered even through the night. The batteries are recharged by your home’s solar PV system every day.
Washington is home to nearly 2,400 employees in 128 small businesses that manufacture or install solar components. Oregon is home to SolarWorld, the country’s largest solar panel manufacturer. The solar industry is adding workers nearly 12 times faster than the overall economy, accounting for 1 in every 83 new jobs across the U.S. Learn more about the benefits of solar in the Pacific Northwest.