What happens to solar powered homes during a blackout?
Most folks assume that solar panels will continue to produce power should the electrical grid go down. It’s a natural assumption. Since the panels only require sunlight to generate electricity, why would a lack of external power matter?
Well, unfortunately, if the grid goes down your solar system will probably be designed to go down with it. But the problem isn’t a lack of power coming in. It’s rather the extra power going out.
NET METERING
Solar systems typically produce more energy than homeowners need during the day when the sun is shining. And, of course, once the sun sets, they don’t generate any.
In order to encourage the transition to clean and renewable energy sources, Pennsylvania and many other states have enacted something called Net Metering, whereby your utility company is required to buy back any extra power you produce at the same price they charge.
That way, the extra power your solar system generates during optimal sunlight is, in effect, stored for later use without the need to install an expensive and environmentally unfriendly battery.
But why would that stop your panels from producing power should the grid go down? Well, from a technological perspective, it doesn’t. So long as the sun is shining, your panels are technically capable of generating solar energy irrespective of any outside factors.
The problem is safety. When the grid goes down, to get it back up again technicians need to be able to work on power lines. So, any occasional bursts of power your solar panels might send back into the grid would constitute a serious hazard.
As a result, if you’ve got net metering, your solar system will be set up to stop producing electricity when the grid goes down to keep any technicians working on power lines safe. The upshot is that if you want your power to stay on when the rest of the neighborhood’s goes down, you’ll still need a backup generator.
BACKUP GENERATORS
Whole home backup generators, also known as standby generators, are large generators able to produce enough power to run an entire home. There are various different kinds, running on either gasoline, natural gas, diesel, or propane. Generac, Kohler, and Cummins are three major manufacturers.
Standby generators have something called an automatic transfer switch or ATS. As the name suggests, when the grid goes down, the ATS automatically switches the power source after starting the generator up.
The good news is that if you didn’t have any need for a backup generator prior to installing solar panels, there’s no reason you’ll need one after switching to solar.
If, however, you live in an area in which power outages are frequent enough that a backup generator is necessary, the other good news is that they’re perfectly compatible with solar panels.
The two systems will, of course, need to be wired properly so that they don’t interfere with one another. If you’ve already got a backup generator and plan on going solar, your solar installer will be able to set everything up properly so the overall system runs exactly as it should and is safe for everyone concerned.
If, however, you already have a solar system and are thinking about adding a backup generator, you’ll need to have a certified electrician do a proper installation.