Solar Energy During Power Cuts: Can Solar Panels Work During Power Outages?
It is no secret that power outages are happening more frequently and lasting longer these days. If you have ever found yourself fumbling in the dark for a flashlight or holding your breath as the food in your fridge gets warmer by the minute, you are not alone.
In fact, in 2024, the number of power outages has spiked dramatically, driven largely by extreme weather events and an overburdened electrical grid. To put it into perspective, states like Texas, which tops the list, have experienced over 210 significant weather-related outages since 2000, and the trend is only worsening.
Now, here is a fact that might surprise you: Experts predict that two-thirds of people in North America could face blackouts this year.
The combination of increased electricity consumption (think of all those devices we can’t live without) and the aging power infrastructure means the grid is under more strain than ever. And while renewable energy is part of the solution, there is a catch—solar panels don’t always keep the lights on during an outage.
So, what’s the deal? Can solar panels actually keep you powered up when the grid goes down?
Can solar panels work during power outages?
The sun is shining, temperatures are pleasant, perfect conditions for your solar panels to produce to their maximum efficiency. There is only one disturbance to this equation, the power has been out since the morning due to some maintenance work or a grid overload in your neighborhood, and you do not have electricity at your home.
Yes, solar panels generate electricity from the sunlight during the day. At least, this is what most people think when they install a photovoltaic system. But many people also get surprised when their solar system disconnects when the grid goes off during the day.
What to do? How do you make sure that your house still has all that power produced by your solar system? Isn’t that why you got solar panels in the first place – to gain some of that energy independence?
Let’s dive into this topic a bit further to learn what options you have and how to tackle this problem.
How solar panels function in a power outage?
Solar panels are pretty amazing technology—they convert sunlight into electricity using photovoltaic cells. These cells are like little energy factories, capturing sunlight and transforming it into direct current (DC) electricity. This DC power then flows into an inverter, which converts it into the alternating current (AC) that powers most appliances in our homes.
But here is the catch: most solar setups you see on homes today are grid-tied systems. This means they are actually connected to the local utility grid. This setup allows you to draw power from the grid when solar panels aren’t producing enough energy (like at night) and send excess power back to the grid during the day. It is a nice setup because it helps to reduce your electricity bill, but there is a catch: during a power outage, these systems typically shut down.
Why? It is a safety feature. When the grid goes down, your solar inverter shuts off to prevent the backflow of electricity. It could endanger utility workers fixing the lines.
On the other hand, are the off-grid solar systems. These setups are designed to be completely independent from the grid. They usually include a battery storage system that stores excess energy produced during the day for use when the sun isn’t shining. During a power outage, an off-grid system doesn’t miss a beat—it just keeps on powering your home from its battery reserve. It makes sense, since it is a stand-alone system.
Why do grid-tied solar inverters shut down during power cuts?
It might seem odd that even when the sun is shining, your solar panels do not keep your electronics on during a blackout. The reason behind this has everything to do with safety and is called “anti-islanding.”
Grid-tied solar systems are designed to work in harmony with the local power grid. When the grid is up and running, your solar inverter works flawlessly. However, if the grid goes down, safety regulations require that your inverter automatically shuts off. This is where anti-islanding comes into play.
Anti-islanding is a safety mechanism that prevents your solar system from continuing to send power into the grid during an outage. It happens because utility workers are out there trying to fix a downed power line, and your solar system would still feed electricity into the grid. This could create a dangerous situation, potentially putting those workers at risk of electric shock.
To prevent this, inverters are programmed to shut down the moment they detect a grid failure.
Off-grid solar systems still work during outages
On the flip side, off-grid solar systems are built to function independently of the grid. These systems include battery storage that holds the excess power your panels produce during the day. This stored energy is what you rely on at night or during a power outage.
With an off-grid system, you are essentially your own mini power station, producing and storing all the electricity you need.
The big advantage here is that off-grid systems continue to provide power even when the grid is down. You are not dependent on the utility company, so a blackout in your area doesn’t affect you.
However, this independence comes at a cost—literally. Off-grid systems are generally more expensive because of the additional components like batteries and backup generators that are needed for a consistent power supply. You also need to consider that batteries have a shorter lifespan than solar panels and will need to be exchanged sooner, again costing you money.
How do solar panels work without a battery?
Photovoltaic solar panels only generate electricity. They are not able to store energy in any way. Solar panels can work without a battery by directly feeding the electricity they generate into the grid or being used immediately by the appliances in your home. However, without a battery, any excess energy generated during the day is lost if it is not used immediately, and you will not have power during a blackout, as your system shuts down for safety reasons discussed above.
Essentially, without a battery, your solar panels are most effective during sunny days and when your energy use aligns with the solar power production.
How to use solar panels during power outage?
But what if you want your solar system to keep running during a blackout? That is where hybrid inverters come in as one possibility if you are not interested in stand-alone off-grid systems.
Hybrid inverters in this case offer a middle ground. These systems are connected to the grid but also include battery storage. During a power outage, a hybrid inverter can switch to using the stored battery power and you still have electricity. Once the grid is back online, the system seamlessly switches back to normal operation, using both solar power and grid electricity.
So in theory, hybrid systems combine the best features of both grid-tied and off-grid solar systems.
Here is a breakdown of how a typical hybrid system operates:
- Solar power generation: During the day, solar panels convert sunlight into electricity.
- Battery storage: Excess electricity generated by the panels (that isn’t immediately used by your home) is stored in a battery system. This stored energy can be used during the night, cloudy days, or during a power outage.
- Grid connection: If your solar panels are not generating enough electricity and your battery is depleted, your system can pull power from the grid. Conversely, if your battery is fully charged and your solar panels are still producing excess energy, that energy can be sent back to the grid, sometimes earning you credits on your electricity bill through net metering.
- Smart inverters: Hybrid systems use smart inverters that manage the flow of energy between your solar panels, battery storage, and the grid, ensuring that power is available when and where it is needed.
When choosing a hybrid solar system, the quality of components like the inverter and battery matters. You want good quality technology to back up your power and last long enough for the investment to be sensible.
Some top options on the market at the moment are systems like the Tesla Powerwall paired with the SolarEdge inverter, which is known for its high capacity, scalability, and user-friendly management.
Another popular choice is the LG Chem RESU combined with the SMA Sunny Boy Storage inverter, offering a compact and durable solution. Other noteworthy systems include the modular Enphase Encharge with the Ensemble system, known for its efficiency, and the premium Sonnen Eco, which excels in energy management and long-lasting performance.
Do I need to reset solar after a power outage?
In most cases, you do not need to manually reset your solar system after a power outage. Modern solar systems, especially those with grid-tied inverters, are designed to automatically reconnect to the grid once power is restored.
The inverter will typically go through a safety check process called “re-synchronization,” which can take a few minutes. During this time, it runs a check that everything is stable before it starts converting solar power to electricity again.
However, if your system doesn’t come back online automatically, you might need to check your inverter or contact your solar installer. There could be issues like a tripped circuit breaker, an inverter fault, or an outdated inverter model that might eventually require a manual reset.
If you are not sure how to check your inverter, start by referring to your system’s user manual for specific instructions related to resetting the inverter after an outage.
