The huge power outage in Texas in February 2021 got a lot of people thinking about solar. But a question quickly came up in all the conversations I had with people around the country. Do solar panels work during a power outage? That sounds like an absurd question. But under some circumstances, they don’t.
Solar doesn’t always work during a power outage, and that’s something that naysayers used to try to pin the blame on solar power. On-grid solar panels will shut down to protect electrical workers during an outage, but there are ways for you to compensate for that.
Why solar panels might not work during a power outage
At first, the idea of solar panels not working during a power outage seems absurd. The sun is still shining. The sun doesn’t care if the power is on or off. But the solar panels care because they’re designed to care.
The reason makes sense once you think about it. If the solar panels are feeding power into the grid while the power is out, that creates a hazardous situation for the workers. The electric company needs to control when the lines are live. So solar panel installations are designed to shut down during power outages to protect the workers. Then, when the system senses the power is back on, the system can start back up again since it can provide power safely, without the potential for loss of life.
Opponents of solar power seize on this to say that solar power isn’t reliable. But that’s an oversimplification. Any well-designed system is designed to shut itself down when it’s not safe for it to operate. On-grid solar is designed to not be 100% reliable because the grid isn’t 100% reliable. But on-grid solar is designed to fail precisely when the grid fails. So that’s an advantage, not a disadvantage.
And of course, off-grid solar doesn’t have to consider the grid. Off-grid solar does work during a power outage, as long as there’s enough sunlight.
How to compensate for solar not working during a power outage
Of course, on-grid solar panel installations have a way to compensate for this safety measure. They can compensate the same way solar compensates for the sun not shining at night. If you have a battery backup, then your house can run off batteries while the power is out. Of course the power goes out once the batteries die, but how long that takes depends on the capacity of your battery system. And you have time to reduce your power usage to the essentials to conserve battery power.
The battery backup is expensive, so not everyone opts to get it. But battery backup is what makes solar power practical. Solar power was a bit of a craze even in the 1980s, but the reason so few people had it then was we had no good way to store the energy for later use. Battery technology is much better now, so that’s why solar power is so much more widespread now.
On-grid vs off-grid
The consideration with solar power is whether you want to be on grid or off. Off grid gives you independence. If you want to be the ideal American rugged individualist, off-grid solar panels provide one of the best ways to do that in history.
But an on-grid system has some advantages too. It allows you to use the grid for backup at night when the sun isn’t shining or on overcast days when they aren’t getting as much sun. It allows you to sell your excess power to the electric company when your panels generate more power than you need. Owners of on-grid solar panels have very low electric bills, when they get a bill. Frequently they get a payment rather than a bill. Whether the payment is big or small depends on how much power they sell. Solar panels can make my energy reduction look downright wussy.
To me, this shows the absurdity of Texas’ decision to not be on the national grid. As much sun as Texas gets, if Texas were on one of the national grids and every Texan had solar panels, it could be selling power to the rest of the country. Texas could be a net exporter of electrical power, the way it was once a net exporter of oil.
But we’re not here to talk about Texas, because I’m pretty sure Texas couldn’t care less what I think. We’re here to talk about you.
If you’re off-grid, you’ll probably have to have a battery, because the grid can’t provide for you.
If you’re on-grid, you’ll need a battery for solar panels to act the way you probably expect them to act. So that means that solar panels actually cost more than the introductory price you may be hearing.
Realistically, I think a usable solar installation requires a battery, whether you’re on grid or off. But that’s a conversation you should really have with your installer.
An alternative approach
You have another option, especially if you have a detached garage or a shed. You can install inexpensive solar panels on the roof to provide off-grid power to the outbuilding. This provides free power to anything you can power from the building, but also provides options to get creative during a power outage. You shouldn’t have an extension cord running across your yard long-term. But during a power outage, it’s solving other problems.
You can get 100 watts worth of solar panels from Harbor Freight for around $200, and there are tricks to get them at steep discounts. Some people will buy these to power their outbuilding and expand the system as they can afford, adding more panels and adding battery backup. It allows one to start experimenting with solar for less than $300, and build on as budget permits. It’s a way to get into the game with solar without spending tens of thousands of dollars. It’s cheaper than running power from the house into the outbuilding would be, in some cases.
And if and when you install solar on your house, then you have a hybrid approach. You can go on-grid for the house, while having off-grid power in your outbuilding.