Power outages are one of those things most people do not think about until they happen. The lights go out, the Wi-Fi drops, the fridge stops humming, and suddenly everyone in the house is asking the same question:
Do we still have power from the battery?
If you have an AlphaESS M10, the answer depends on how your system was designed and installed, but the M10 has been built with backup capability in mind. In the right installation, it can help keep your home running when the grid is unavailable.
This article explains what happens during a power outage, how backup power works, what the battery reserve setting does, and what homeowners should understand before relying on backup power.
What Happens When the Grid Is Working Normally?
Under normal conditions, your AlphaESS M10 works quietly in the background, managing energy between your solar panels, battery, home and the grid. During the day, your solar power can supply the home first. Any extra solar energy can be stored in the battery for later use. In the evening, when solar generation drops, the battery can discharge to help power the home and reduce the amount of electricity you buy from the grid.
The grid is still there when needed, but the system’s job is to help you use more of your own energy first.
Most of the time, homeowners do not need to think about this process. The system simply manages the energy flow automatically.
What Happens When the Grid Goes Down?
When the grid goes down, the M10 detects the outage and automatically switches to backup operation. This changeover is designed to be seamless. The M10 has a fast backup changeover time of around 20 milliseconds, which means most customers should not notice the lights flicker, the TV switch off or a computer suddenly shut down. From the homeowner’s perspective, the goal is simple: the power stays on. Behind the scenes, the system safely separates your home from the grid. This is important because during an outage, your battery system must not send power back into the electricity network. It needs to protect your home, while also protecting people who may be working on the grid.
Once the system is in backup mode, the M10 can continue supplying power to the backed up part of your home using energy from the battery and, depending on your solar design, energy from your solar panels.
Whole Home Backup or Selected Circuit Backup
One of the most important points to understand is that backup power depends on how the system was installed. The AlphaESS M10 has whole home backup capability. This means it can be designed to support the whole home, within the power limits of the inverter, battery and installation. However, not every home is installed the same way.
Some systems are installed for whole home backup, where the backup supply is designed to support the main household loads. Other systems are installed for selected circuit backup, where only specific circuits are connected to backup power. These may include essential items such as lights, fridge, internet, garage door and selected power points.
Both designs can be suitable. It depends on the home, the switchboard, the appliances, the customer’s expectations and the installer’s design.
A simple way to think about it is this:
The M10 has the capability to support whole home backup, but what actually stays on during an outage depends on how your installer wired and configured the system.
That is why it is important to ask your installer which parts of your home are backed up.
The M10 has the capability to support whole home backup, but what actually stays on during an outage depends on how your installer wired and configured the system.
That is why it is important to ask your installer which parts of your home are backed up.
What Can You Use During an Outage?
During an outage, backup power should be treated differently to normal grid power. When the grid is available, most households do not think too much about turning on the kettle, oven, air conditioner, dishwasher, pool pump or EV charger. During a blackout, those choices matter more because every appliance uses battery energy. The more power you use, the faster the battery will discharge.
For most homes, the priority should be keeping essential loads running for as long as possible. That usually means the fridge, freezer, lights, internet, phone charging, security system, garage door and key power points.
This does not mean you cannot use other appliances. It simply means you should be aware that large loads can reduce your available backup time very quickly. Backup power is about comfort, safety and continuity. It is not always about running the home exactly as if the grid was still available.
For most homes, the priority should be keeping essential loads running for as long as possible. That usually means the fridge, freezer, lights, internet, phone charging, security system, garage door and key power points.
This does not mean you cannot use other appliances. It simply means you should be aware that large loads can reduce your available backup time very quickly. Backup power is about comfort, safety and continuity. It is not always about running the home exactly as if the grid was still available.
Should I Backup My Air Conditioner or EV Charger?
This is one of the most common design questions, and it is worth thinking about before installation.
Air conditioners and EV chargers can use a lot of power. In some homes, they may be among the largest loads on the property. A small split system air conditioner may be reasonable to include in some backup designs, depending on its power draw and what else is running at the same time. A large ducted air conditioning system is a very different situation. It may require a much higher amount of power and could drain the battery quickly. EV chargers are usually even more important to consider carefully. Charging an electric vehicle from the home battery during a blackout can use a large amount of stored energy. In many cases, it makes more sense to preserve battery capacity for the home rather than use it to charge the vehicle.
Our general recommendation is to backup the essentials first. Once those are covered, your installer can help assess whether larger loads such as air conditioning or EV charging should be included. The right answer depends on the size of the appliance, your battery capacity, your inverter capacity, your switchboard design and how long you want backup power to last.
Air conditioners and EV chargers can use a lot of power. In some homes, they may be among the largest loads on the property. A small split system air conditioner may be reasonable to include in some backup designs, depending on its power draw and what else is running at the same time. A large ducted air conditioning system is a very different situation. It may require a much higher amount of power and could drain the battery quickly. EV chargers are usually even more important to consider carefully. Charging an electric vehicle from the home battery during a blackout can use a large amount of stored energy. In many cases, it makes more sense to preserve battery capacity for the home rather than use it to charge the vehicle.
Our general recommendation is to backup the essentials first. Once those are covered, your installer can help assess whether larger loads such as air conditioning or EV charging should be included. The right answer depends on the size of the appliance, your battery capacity, your inverter capacity, your switchboard design and how long you want backup power to last.
Can Solar Still Work During a Power Outage?
This depends on how your solar system is connected.
If your solar panels are wired directly into the AlphaESS M10 hybrid inverter, this is commonly understood as a DC coupled design. In this setup, your solar can continue generating during a power outage, provided there is enough sunlight and the system is operating within its limits. This can be a major benefit. During the day, solar can help power your home and recharge the battery while the grid is still down.
If your home has a separate solar inverter from another brand, and the AlphaESS battery has been added alongside it as an AC coupled system, that separate solar inverter will normally shut down when the grid goes down. This means your battery can still provide backup power, but the separate solar inverter will usually not keep generating during the outage.
For homeowners, the easiest way to understand it is: If your solar is wired through the AlphaESS hybrid inverter, solar can usually keep helping during an outage. If your solar is running through a separate solar inverter, it will usually stop during an outage. Your installer can confirm which design you have.
If your solar panels are wired directly into the AlphaESS M10 hybrid inverter, this is commonly understood as a DC coupled design. In this setup, your solar can continue generating during a power outage, provided there is enough sunlight and the system is operating within its limits. This can be a major benefit. During the day, solar can help power your home and recharge the battery while the grid is still down.
If your home has a separate solar inverter from another brand, and the AlphaESS battery has been added alongside it as an AC coupled system, that separate solar inverter will normally shut down when the grid goes down. This means your battery can still provide backup power, but the separate solar inverter will usually not keep generating during the outage.
For homeowners, the easiest way to understand it is: If your solar is wired through the AlphaESS hybrid inverter, solar can usually keep helping during an outage. If your solar is running through a separate solar inverter, it will usually stop during an outage. Your installer can confirm which design you have.
What Is the Battery Reserve Setting?
The battery reserve setting is one of the most useful backup features in the AlphaESS app. It allows you to keep part of your battery capacity aside for backup use. This means the battery does not need to discharge all the way down during normal daily operation. For example, if you set your reserve to 20%, the system will aim to keep that portion of the battery available in case there is a power outage.
This setting helps balance two different goals.
The first goal is everyday energy savings. You want to use your battery to reduce grid electricity use, especially in the evening or during peak tariff periods.
The second goal is backup protection. You may want to keep enough energy in the battery so your home has power available if the grid goes down.
A lower reserve gives you more battery capacity for everyday use. A higher reserve keeps more energy available for backup. There is no single perfect setting for every household. If you rarely experience outages and want to maximise daily battery use, you may prefer a lower reserve. If you live in an area with more frequent outages, or you want greater backup confidence, a higher reserve may make more sense. The important point is that the reserve setting does not create extra battery capacity. It simply controls how much of your battery is protected for backup use.
This setting helps balance two different goals.
The first goal is everyday energy savings. You want to use your battery to reduce grid electricity use, especially in the evening or during peak tariff periods.
The second goal is backup protection. You may want to keep enough energy in the battery so your home has power available if the grid goes down.
A lower reserve gives you more battery capacity for everyday use. A higher reserve keeps more energy available for backup. There is no single perfect setting for every household. If you rarely experience outages and want to maximise daily battery use, you may prefer a lower reserve. If you live in an area with more frequent outages, or you want greater backup confidence, a higher reserve may make more sense. The important point is that the reserve setting does not create extra battery capacity. It simply controls how much of your battery is protected for backup use.
What Happens to the Reserve During an Outage?
When the grid is available, the system will try to protect the reserve level you have selected. When the grid goes down, that reserved energy becomes available to support your backed up loads. That is the purpose of the reserve. It is energy kept aside so the battery is ready when backup power is needed.
How long the battery lasts will depend on how much energy is stored, how much reserve you have set, whether solar is available, and how much power your home is using during the outage.
A home running lights, fridge, internet and a few small appliances will use far less energy than a home running air conditioning, cooking appliances or EV charging.
How long the battery lasts will depend on how much energy is stored, how much reserve you have set, whether solar is available, and how much power your home is using during the outage.
A home running lights, fridge, internet and a few small appliances will use far less energy than a home running air conditioning, cooking appliances or EV charging.
What Happens When the Grid Comes Back?
When grid power returns, the M10 will reconnect to normal operation. Your home can again use solar, battery and grid power as usual. If the battery has discharged during the outage, it can recharge again from solar or from the grid, depending on your system settings and energy plan. For most homeowners, this process happens automatically. The system moves from normal operation, to backup operation, and then back to normal operation once the grid is restored.
What Should Homeowners Check Before an Outage?
The best time to understand your backup setup is before the next blackout, not during one.
It is worth asking your installer a few simple questions. Is my system installed for whole home backup or selected circuit backup? Which appliances are backed up? Will my solar continue working during an outage? Is my air conditioner included? Is my EV charger excluded? What battery reserve setting should I use?
These are practical questions, and the answers will depend on your home. The M10 gives homeowners strong backup capability, but good backup performance also depends on good system design, correct installation and realistic expectations about what the battery should support during an outage.
It is worth asking your installer a few simple questions. Is my system installed for whole home backup or selected circuit backup? Which appliances are backed up? Will my solar continue working during an outage? Is my air conditioner included? Is my EV charger excluded? What battery reserve setting should I use?
These are practical questions, and the answers will depend on your home. The M10 gives homeowners strong backup capability, but good backup performance also depends on good system design, correct installation and realistic expectations about what the battery should support during an outage.
Final Takeaway
The AlphaESS M10 is designed to help your home use more solar energy, reduce grid reliance and provide backup power when the grid is unavailable. When the grid is working normally, the system manages energy between your solar, battery, home and the grid. When the grid goes down, the M10 can automatically switch into backup mode and continue supplying power to your home or selected circuits, depending on how the system was installed.
The experience is designed to be seamless, with fast changeover so everyday devices like lights, TVs and computers can continue operating without interruption.
For homeowners, the most important message is simple: Backup power works best when the system has been designed around your home, your appliances and your expectations. With the right setup, the AlphaESS M10 can provide more than stored solar energy. It can provide greater confidence when the grid goes down.
The experience is designed to be seamless, with fast changeover so everyday devices like lights, TVs and computers can continue operating without interruption.
For homeowners, the most important message is simple: Backup power works best when the system has been designed around your home, your appliances and your expectations. With the right setup, the AlphaESS M10 can provide more than stored solar energy. It can provide greater confidence when the grid goes down.