Image: Vika200581 – Depositphotos.We assume that we have solar panels on the roof and we produce a large part of our electricity, the electricity bills have been reduced considerably.
Then, one windy night, a storm knocks down a huge tree in your neighborhood and the power goes out. At dawn, will your refrigerator still work? Probably not.
If you have solar panels on your roof, chances are you are connected to the commercial power grid. This means that at night or when your panels are not producing enough, you get electricity from the power company. You also send power to the grid when your panels produce more than you consume.
In the event of a power outage, most solar home systems are designed to shut down to prevent them from feeding power back into the very wires that could be causing the outage. After all, they don’t want your solar panels to be the reason power company workers are injured from the stress of downed power lines.
But then what good are solar panels on a roof if they can’t produce electricity?
There must be a way to keep the energy, right? What about batteries or preventing solar power from flowing into the grid when the grid is down? We talked about possible solutions.
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Why don’t solar panels work in the event of a power outage?
Most solar home owners have what is called a “grid tie” solar system, which means the panels are connected to a solar inverter.
The inverter is connected to the main AC panel of the house and to a special smart electricity meter which registers both the energy consumed by the electricity company and the energy sent by the solar panels to the grid. Grid-tied solar systems operate without any backup battery equipment.
This is why it is often said that “the network is your battery“. When your solar system produces excess electricity, you send it to your neighbors and benefit from it (thanks to net metering), but when the sun goes down, you still need electricity from the utility grid. If you do the math right, you can have an electricity bill close to 0.
In case of failure, a typical grid-connected system has a special automatic shutdown system to prevent this extra power from being sent over potentially damaged power lines. This is a safety device intended to protect linemen traveling to repair them in the event of a breakage.
But it also means your home is not getting solar power. In the event of a power outage, the energy from your solar panels doesn’t go anywhere unless you have a way to store the electricity (like a battery) or separate the system from the grid.
How to use solar energy in the event of a breakdown?
If you want your home to continue running in the event of a power outage, there are several ways to do so:
- Use a backup gasoline generator.
- Add solar batteries to your system.
- Use a solar powered generator.
- Replace your inverter with a Sunny Boy or Enphase Ensemble system.
Emergency gasoline generator.
Solar power lovers aren’t usually fans of burning electricity, but the cheapest way to ensure you have backup power in the event of a power outage is to purchase a generator.
With a generator, you can get over 9,000 watts that can run most of your home while power company workers reconnect the grid.
With your generator and some fuel, you’ll usually be able to ride out any extended grid outages and even help out a neighbor if they need it. Your solar panels will stay off until the grid comes back on, but at least you’ll have power.
But in my opinion, generators are not a good option beyond their low price. I prefer the following suggestions.
Solar battery.
For true peace of mind during a power outage, there’s nothing better than a solar battery system.
There’s nothing like the feeling of being the only house on the block with the lights on after a power outage.
There are many options available, from a deep cycle lead acid battery bank to the sleek and easy to use Tesla Powerwall.
Today’s solar installers are very experienced in installing batteries alongside solar installations, and you might be surprised at the number and variety of alternatives on the market.
Unlike solar power without batteries (i.e. a solar system connected to the grid), a solar installation with batteries keeps its energy on the “grid”, or disconnects from the grid when a power outage occurs. detected. During the blackout, your little solar island will charge the batteries during the day and discharge them at night. As long as it has enough battery capacity, it can continue to operate like this during a very long outage.
solar generator.
If you’re not ready to invest in whole-house batteries, there are also “solar generators” that can at least keep your food cool and a heater running.
Just keep in mind that these portable options can be charged with or without solar panels when the grid is up, but again they won’t charge from solar power when the grid is down without the same type of special equipment used for a more complete solar storage system.
A special inverter or an inverter system.
Fortunately, there is a way for a solar-powered homeowner to utilize the energy produced by their panels without a grid connection or energy storage system.
SMA and Enphase, for example, are two companies that make special solar inverters designed to automatically disconnect from the grid in the event of a power outage, while still powering your home from your solar panels.
While most solar inverters have that automatic shutdown we talked about earlier, SMA Sunny Boy inverters can be installed with a special circuit that allows homeowners to switch to pure solar power after a power outage.
Enphase is another company that has gone to great lengths to make solar power work when the grid fails. The company’s Ensemble energy management system works with its microinverters to power your appliances from your solar panels whenever the sun is bright enough, even without batteries.
Why not disconnect from the commercial network?
People who want to completely ditch fossil fuels and ensure that they only use clean energy at home may be tempted to completely disconnect from the grid. And that’s an option, but the initial investment is more expensive.
Although solar power has never been cheaper than it is today, it is still a great investment. An off-grid solar system with battery storage will cost a little more than an on-grid system.
Additionally, off-grid battery storage should be able to supply the right amount of electricity you might need for three cloudy or snowy days during the coldest part of winter, wherever you live. During the sunniest months you will certainly have energy to spare, but you don’t want to run out of energy and have to resort to a fossil fuel generator during the winter.