Power outages in the United States have increased by roughly 285% since the 1980s, according to a report by the International Business Times. Each one of these blackouts cost up to $150 billion in lost productivity, business downtime, and other related expenses.
Being that solar power systems generate their own electricity through sunlight, you might assume that solar panels will keep the lights on when the local grid goes out, but this isn’t necessarily true. Assuming you have a traditional grid-linked solar power system, it will also go down during power outages. There are a few different reasons for this, which we’re going to discuss.
A Technical Review
Solar power systems are designed to automatically adjust voltage and current depending on sunlight and other factors to ensure the highest level of efficiency. This process requires power, which the system may need to draw from the connected grid. If the grid is offline, it won’t have the power to adjust the voltage and current. As a result, the system would perform poorly while also increasing the risk of damage to electrical appliances.
The second, and most important, reason why solar power doesn’t work during power outages is for safety. When a severe storm topples trees and brings down power lines, the power company will send crews to repair the damaged line. For safety reasons, all power must be shut off from the line on which the crews are working; otherwise, there’s a very real risk of electrocution or shock.
Since most residential solar power systems are connected to the grid, they are designed to automatically shut off when the grid goes down to protect linemen from danger. Normally, a residential solar power system will produce and sell excess energy to the grid, for which the homeowner receives credits. This means the homeowner’s solar power system is constantly connected to the grid. As a result, it poses a risk to linemen working to restore power during outages – unless, of course, the solar power system is deactivated.
There are ways to keep a solar power system running during power outages without jeopardizing the safety of crewmen. A backup battery, for instance, can store solar power for use later, such as during power outages. The solar panels don’t technically “work” during this time, but instead the home can draw power from the battery. Ultimately, though, solar power systems are forced to shut down during power outages for safety and technical reasons.