Do Solar Panels Work During Blackout Events?

You might've heard that solar can keep the lights on during blackouts. So, do solar panels work during blackout conditions?

UPDATE: AlphaESS has been named a Top Brand by German-based EUPD Research.

Let’s paint a picture. It’s a dark, windy night. So windy, in fact, that tree branches have fallen from several trees, knocking down an overhead powerline. It sparks on the asphalt. 

The neighbourhood is a sea of blacked-out windows, the odd candle dimly flickering. But in the centre of that great ocean of darkness, one house stands out. Light streams from the living room window, illuminating a family plucking cold drinks from their fridge. If you listen closely, you can hear the chime of an iPhone connecting to its charger.

What makes that house different? If you guessed solar power, you’re right. But it’s a little more complicated than that. That house has a complete solar system, with solar panels and a solar battery. The solar battery is the key. Why? Because a solar battery allows you to store power to use when the grid fails.

Read on to learn exactly how a solar & battery system can keep your lights on when the rest of the street goes dark. Or book a free consultation right now and our experts will help you make blackouts a thing of the past.

Do Solar Panels Work During Blackout or Brownout Events?

There’s a big misconception that if you have solar panels, you’re automatically covered in the case of a blackout. Unfortunately, that’s not true. Your solar system is connected to the grid, so running your system like normal during a blackout could result in your solar power going back onto the grid. And this can cause real-life consequences, like zapping an electrical worker as they try to fix the line. So, do solar panels work during blackouts or not? The answer is not as complicated as it seems.

There is a way that you can continue to use panel-generated power during a blackout. All it takes is a solar battery! Typically, solar batteries are designed to store energy generated by your panels during the day. That energy is then used to power your home at night. But some solar batteries can supply power to your home during blackouts too!

Many solar batteries feature a ‘blackout mode’. This mode kicks in automatically when the grid fails as long as the battery has enough energy stored. The battery delivers power to your most essential appliances and circuits.

It’s important to note that blackout protection is not included automatically with every solar battery. So, if blackout protection is something you want, make sure you select a battery that has that capability and is paired with a hybrid inverter. Popular battery brands with blackout protection include AlphaESS, LG Chem, and Growatt.

We’ve assembled the chart below to give you an idea of what’s out there:

Battery Model Battery Capacity Max Inverter AC Power Output – Blackout Mode Max Inverter AC Power Output – Normal Operation Battery DC Charge/Discharge current
ALPHA ESS 5.7kWh 5.7 kWh 4600 W/22A** 5000W/21A 100A
ALPHA ESS 10.1/10.3 kWh 10.1/10.3 kWh 4600 W/22A 5000W/21A 100A
ALPHA ESS 10.1/10.3 kWh 10.1/10.3 kWh 5000 W/22A 5000W/22.8A 100A
LG Chem RESU10H 9.8 kWh 5000 W/22.8A (3300W recommended) 5000W 11.9A to 14.3A
LG Chem RESU13 LV 13 kWh 5000W/22.8A (3300W recommended) 5000W 65A/50A
Telsa Powerwall 2 14 kWh 5000W/21A per Powerwall 5000W/21A 100A
Growatt GBLI6532 6.5kWh 3000W 5000W/22A 66A

*Please note that this data is sourced from publicly available datasheets as of 11 August 2020 and is subject to change.
**To reach 4.6kW power output, you must have at least two 5.7kWh batteries. If you have only one battery, the maximum output will be limited to 2.3kW.

One last thing to remember – when it comes to blackouts, inverters matter!

If being protected during a long blackout is important to you, make sure your solar system has a hybrid inverter. Many battery retrofit systems that connect onto existing solar panel systems don’t allow you to charge your battery during the blackout period.  In that case, once you drain your battery, you will be left without power until the grid comes back. A hybrid inverter controls both your panels and your battery. This means you can recharge your battery from your panels even in blackout mode. A good example of this is the Alpha ESS Hybrid inverter.

What Appliances Can I Run During a Blackout?

Take a second and think about the most annoying parts of a blackout.

Done? Great!

If you thought about stumbling through darkened rooms, rationing your phone battery, and wondering how long until the food in your fridge spoils – we’ve got good news for you! These are exactly the kinds of things that blackout protection is designed to prevent.

Blackout protection ensures that you can continue to supply power to a couple of key circuits and appliances. It’s all about the maximum output of the battery and hybrid inverter, so you’ll have to make some decisions. But generally speaking, you’ll be able to keep some lights on, power the fridge, charge your phone, and keep your internet on. Normally, the installer will choose 2-3 circuits for backup power to cover. One of these circuits will cover some lights, and one will cover a fridge and some powerpoints.

Imagine watching the rugby with a cold beer while all your neighbours rummage around for candles. If you’re in a generous mood, you’ll be the most popular person on the block!

Do solar panels work during blackout events?

Ready to say goodbye to blackouts forever? Then say hello to our experts, who’ll help you set up your perfect solar solution. If you need more information, we’ve answered some of the questions we’re most frequently asked below.

Frequently Asked Questions

What exactly are blackouts?

A blackout is caused by a complete loss of electricity connection. It can be caused by a number of factors including extreme weather or the local grid having more power than it can handle or not enough power to meet demand.

Do Solar Panels Work During Blackout & Brownout Events?

Not without a solar battery to store the power your panels generate. Without a battery, the panels need to shut off for the safety of workers trying to fix the grid. But if you have a solar panel, you can continue to use the panel-generated power you’ve stored.

How does blackout protection work?

Blackout protection uses your battery to power certain essential appliances. Usually, you can power some lights, a fridge, and a power point or two for charging phones and running other appliances.

The setup is pretty simple. A separate output cable runs from the battery and hybrid inverter to a selected number of circuits in the switchboard. This connection is protected by a main battery circuit breaker and one changeover switch for protection.

Can I have blackout protection installed with my battery system?

In most cases the answer is yes but it depends on the product you select, the condition of the switchboard, and where the battery is installed.

How many circuits can I have on backup and what is the maximum output?

The output of your blackout protection is limited by the maximum output of your battery and/or inverters. To make it simple: let’s use the AlphaESS battery as an example. If your AlphaESS battery is connected to a 5kW inverter, your backup power is limited to 4.6 kW. That’s equivalent to 22A.

That means you can usually run about 1-3 light and power circuits that have a maximum demand of less than 20A.

Can the entire house power during blackout mode?

Usually, no. There are a number of factors that prevent you from doing this. Top of that list is your battery’s output limit.

Your house probably has a maximum power demand of 60-80A. That’s 3-4 times higher than most battery models. Attempting to power your whole house with your battery, can easily overload and shutdown your system. Then you’re right back where you started. Your home is just another dark house on the street. Powering only your essential appliances lets you keep things up and running when everything else fails.

Engines and pumps will not be covered by blackout protection. Even when they’re described as super-efficient, engines and pumps have a very high start-up amperage (usually above 20A). Ordinarily, even when you have a solar battery, grid energy is used for start-up and then the battery kicks in. The battery can’t handle the high power demand at start-up, and so the whole battery will shut off.

What can be covered by blackout protection? What can’t be?

We generally see that lights, fridges, TVs, computers, internet routers, ovens and cookers are acceptable.  The most important thing is that the power rating of the appliance must be below the battery’s maximum output.

Unaccepted appliances are typically any types of pumps, air conditioners, heaters, vacuum cleaners, or high-powered appliances that require a high start-up current.

Your inverter will usually come with documents outlining what can be covered by blackout protection. But we’ll walk you through it during your free consultation and installation too!

Is the blackout protection automatic when there is a blackout?

In most cases, yes.  You need to confirm your battery inverter has that functionality, but most do.

Can my battery still charge from my solar panels during a blackout?

It depends on the make and model of the battery inverter. If it is connected directly to a hybrid inverter with panels (like the ALPHA ESS SMILE5 or SolarEdge SE5000 for example), then yes. If it is AC-Coupled to an existing grid-connected solar-only inverter, then most likely it cannot charge from your solar panels during a blackout.

Can I have blackout protection on all three phases?

It depends on what type of inverter is installed. Single-phase hybrid inverters only provide blackout protection for a single-phase circuits, so you would need to choose one circuit on one phase for the blackout protection to use when activated.  You cannot have power going to all three phases when you are in blackout mode unless you have a separate battery for each individual phase.

Whether your mind’s made up or you still have more questions, we can help! Book a free consultation and see if blackout protection is the right choice for you!

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