Do solar batteries work in a blackout?

Fast read

Not all solar batteries offer blackout protection. Many batteries prioritise load shifting, storing excess daytime solar power for nighttime use. Some battery systems can provide blackout protection if they have grid-forming components, increasing their cost by around $2000.

If you haven't specified blackout protection as a requirement, you might not have received this feature. If a blackout occurs and the battery doesn't work, consider the frequency and duration of blackouts in your area before investing in an upgrade. Some batteries with blackout protection can't charge during outages, limiting their usefulness.

There are varying backup speeds, from instantaneous (UPS) to delayed (EPS and longer delays). For blackout protection solutions, consult your solar installer for upgrades or replacements. Always seek advice from trusted solar professionals when considering solar or battery purchases.

Will my solar battery work in a blackout?

This can happen, as not all battery solutions available on the market can provide backup and therefore power to the home in the case of a blackout. It’s important to understand that the functionality of batteries during a blackout relies on specific technical configurations and not every solar battery combo, especially the cheaper versions is designed with this important feature. The lack of blackout protection in some systems can be a surprising and unfortunate realisation, especially during emergency situations when power is crucial.

For some purchasers of batteries, the reason for adding them is not necessarily for blackout protection. The primary financial value of batteries can be for load shifting or arbitrage. Load shifting means, storing the excess solar power that cannot be used during the day when it is generated so that it can be used either at night or other peak periods when the home is using more power than the solar panels are generating.

Less reliance on the grid means lower electricity bills

This aspect of energy storage allows homeowners to maximise the generated solar energy and potentially reduce their electricity bills by lessening their reliance on the grid during peak hours.

We expect the solar salesperson to inquire about your blackout power needs during the initial system design and quote. However, this isn’t always the case. If you haven’t explicitly stated it as a requirement, a solar battery with backup capacity for blackout power might not have been proposed.

The communication between the homeowner and the solar company is crucial to ensure that all the desired features are included in the solar battery system. It’s advisable for the customer to have a checklist of essential features they want from their solar battery system before engaging with a solar salesperson.

SMA solar battery with blackout protection

Home batteries equipped with backup capabilities can provide electricity during blackouts or grid outages

Should home storage batteries provide blackout protection?

Home solar battery systems that can provide blackout protection need to have parts that allow them to become “grid forming” when the home loses connection to the grid. Having blackout protection improves the reliability and resilience of your home energy system. It’s a helpful feature for those living in areas prone to power outages or severe weather conditions.

Home solar battery systems that can provide blackout protection need to have parts that allow them to become “grid forming” when the home loses connection to the grid. This is where the battery inverter basically provides a signal/frequency guide for the solar inverter and battery to use as a signal to switch on. You will find that this function can add around $2000 to the cost of the solar battery solution.

This is where the battery inverter basically provides a signal/frequency guide for the solar inverter and battery to use as a signal to switch on. You will find that this function can add around $2000 to the cost of the battery solution. This cost could be justified by the peace of mind and convenience it provides during unexpected power interruptions.

No backup – why have the solar battery in the first place

Some of the standard solar batteries offered on the market do not have blackout protection as standard. As mentioned above these models are primarily designed to store unused solar that is generated during the day so that it can be used at night or in peak demand periods. Additionally, some of these solar battery solutions can be upgraded later on to add a backup box that will enable power during a blackout.

If one logically expects complete blackout protection as a part of a solar battery purchase, the reality is that if you don’t specifically request it, you might receive a battery solution that does not provide this function. Discovering this fact only during a blackout results in deserved surprise and disappointment, as you should have been informed about this “shortfall.”

It underlines the importance of thorough research and effective communication with your solar provider to ensure that all your expectations are met.

What to do if my battery does not work during a blackout?

If you are in a situation where the battery does not work during a blackout, then you have a few options. Understanding your system’s limitations and planning ahead can significantly mitigate the inconvenience caused during a blackout.

Consider how often you experience a blackout and whether it is worth the additional expense of adding battery protection. If you rarely have blackouts and they are only short, you may decide that paying an extra $2000 or more is not worth the benefit of having power for those rare and short periods that you may have a blackout.

Furthermore, some battery systems that do offer blackout protection by being able to power the home from the batteries are not able to charge the batteries from the panels during a blackout. In this case, you will only have power to the house while the batteries have power. When the solar battery runs out of charge power will be lost. If you want blackout protection and have longer blackouts you may want to be able to have the panels charging the batteries during a blackout which will enable the home to run longer during a blackout.

girl doing work in blackout

It is also worth considering the changeover speed when the backup power kicks in. As there are a few different levels. Quick changeover time is a crucial factor that can help maintain essential home operations seamlessly.

Uninterrupted Power Supply

UPS or uninterrupted power supply is the fastest where the power to the home is “uninterrupted”. This means that the battery starts instantaneously, and you may not even notice that you have experienced a blackout. This is the gold standard of blackout protection, providing a seamless transition between grid power and battery power, ensuring that your critical appliances stay on without a hiccup.

Emergency Power Supply

EPS or Emergency power supply will generally take a few seconds for the solar battery to kick in in the case of a blackout. You would notice either a flicker in the lights and power or that the power is lost for a few seconds before the battery kicks in. While it might not be as instant as a UPS, an EPS still provides a rapid response to power outages, ensuring your essential loads are back online quickly.

Then there is another level of backup which can take 30 seconds or longer to changeover to the battery when you lose grid power. This level may be acceptable for some homes, but the delay could be inconvenient or problematic for others, especially if sensitive electronics or critical medical equipment are in use.

How can you get a solar battery that covers blackouts?

Reach out to your solar installer and discuss the options with them to replace or upgrade the batteries. Depending on which battery solution they used it may be simply adding a backup box to the existing inverter. If there is no backup box available for the solution, then they may have to swap out the original battery solution to upgrade it to a blackout-ready solution, which will be a little bit more expensive. If the battery solution is only recently installed and still in good condition the Solar company should be able to offer a trade-in discount for the swap out of the original battery and installation to the blackout-capable solution.

Talking with a knowledgeable solar installer is key. They can guide you through the available solutions that meet your specific needs and budget. In addition, inquire about warranty and support services to ensure you’re making a well-informed decision. It’s wise to have a clear understanding of the long-term benefits and any extra costs involved in upgrading your solar battery system for blackout protection.

Notify of
Inline Feedbacks
View all comments

Find your local installer