Solar battery backup power in Traralgon
Keeping the fridge, lights and modem running in a Latrobe Valley blackout: why most solar switches off and what a backup capable battery system needs.
Most rooftop solar in Traralgon stops working the moment the grid goes down, even on a sunny day and even with a battery fitted. To keep the fridge, lights and modem going during an outage you need a battery and inverter designed for backup, wired so the house can disconnect from the grid and run on its own. Any system you enquire about here is designed, quoted and installed by an independent electrical business; this site only puts you in touch.
Why does my solar switch off in a blackout?
Solar Victoria explains that a standard grid connected system, with or without a battery, shuts down during an outage. That protects line workers repairing the network and stops your system pushing power into lines that are meant to be dead (Solar Victoria on backup power).
A backup capable system is different. It uses a multimode or hybrid inverter and a battery set up to island the home: when the grid drops, the system separates from it and keeps supplying the circuits it is wired to. Whether a given system can do this depends on the inverter and on the design as a whole, rather than on the battery brand. Backup can cost more than a battery set up only for bill savings, and your wiring or circuits may need changes to make it work.
How often does the Valley lose power?
Two recent storms show how supply here can fail, one statewide and one local to the Valley:
| Event | What happened | Source |
|---|---|---|
| 13 February 2024 storm | Six 500 kV transmission towers fell near Anakie, all four Loy Yang A units disconnected, and distribution outages peaked with about 530,000 Victorian customers off supply. About 90% were reconnected within 48 hours. | Energy Networks Australia |
| 1 to 2 September 2024 storm | AusNet reported 12,147 Latrobe Valley customers off supply after 86 incidents, including 407 life support customers. Traralgon had 3,106 outages, the most of any Valley suburb. | Latrobe Valley Express |
Storms bring down lines on any network, and two events do not predict the next one. They do show that a Traralgon household can lose supply for long enough to spoil a fridge full of food, which is the usual reason people start asking about backup. The Traralgon area page has more on local conditions, and households on bigger blocks north of town will find the Tyers area page useful.
Which circuits should stay on during an outage?
A backup system usually supplies a chosen set of essential circuits rather than the whole house. Solar Victoria notes islanded systems typically run lights and the fridge. Deciding what goes on the backup board is the most important part of the design, and it is your call, guided by the installer.
| Load | Questions to settle with the installer |
|---|---|
| Fridge and freezer | Which circuit or power point are they on, and is it shared with anything heavy? |
| Lights | All lights, or only some rooms? |
| Modem and phone charging | Is the modem on a circuit that can be moved to the backup side? |
| Gas heater or gas hot water | Does the appliance need mains power for its fan, controls or ignition? |
| Water pump | Does a rainwater or bore pump need to keep running? |
| Electric cooking, heating and hot water | Is the battery big enough, or is it better to leave these off the backup board? |
The last row matters more as homes move off gas. Solar Victoria’s power outages page points out that all-electric homes are more affected by outages because the cooktop, heating and hot water all stop, and that modern gas heaters and most gas hot water systems also need electricity to run. If your home is going all-electric, the all-electric homes page covers the planning side.
What does a backup capable design need?
Ask any provider to show you, on the quote, how each of these is handled:
- An inverter that supports backup. A hybrid or multimode inverter, or a battery with its own backup function. Some inverters that accept a battery cannot island the home.
- A backup or essential circuits board. The chosen circuits are moved onto a separate section of the switchboard that the battery can supply.
- Automatic changeover. How the system detects the outage, how quickly it switches, and whether anything in the house will reset or blink off in the gap.
- Battery capacity matched to the loads. Enough usable storage to run the essential circuits for the length of outage you care about.
- Solar recharging while islanded. Whether the panels keep charging the battery during a daytime outage, which depends on the inverter and design.
- A clear shutdown procedure. Displayed near the switchboard or inverter, with the battery covered.
Battery sizing for everyday savings is covered on the home battery installation page. For backup, the sum changes: list the appliances you want running and for how many hours, and the installer works backward to a capacity. Solar Choice’s national average for a 10 kWh usable battery, installed with the federal discount, is $7,784 to $8,284 per system, before any extra for backup wiring (Solar Choice battery prices). Ask for the backup work to be priced as its own line so you can see what it adds. If you already have a battery, send its model in a battery backup enquiry and a provider can tell you whether it can be set up for backup at all.
How do I know the backup works before a real outage?
Ask for a demonstration at handover. With you watching, the installer can turn off the main supply at the switchboard and show the essential circuits staying on, then restore supply and show the system reconnecting to the grid. Check the fridge, lights and modem are all on the backed up side, and note anything that went off that you expected to stay on. It is much easier to move a circuit while the electrician is still on site than after the first storm. Keep a written note of which circuits are backed up near the switchboard so everyone in the house knows.
What if someone at home relies on medical equipment?
Solar Victoria says to get specialist advice for medical equipment, because home batteries are typically not appropriate as the primary power source for it. Treat a battery as a convenience for the fridge and lights, not as the plan for life support or other critical equipment. If someone in the house is registered as a life support customer, keep using the arrangements your retailer and distributor have in place and ask the equipment supplier what backup they recommend.
Will a VPP battery work in a blackout?
It might. Solar Victoria notes that batteries enrolled in a virtual power plant may provide some backup, but they are not customised for it. If backup is your priority, say so before you sign up to any VPP offer, and ask the operator in writing what the battery will do, and how much charge you can count on, when the grid goes down.
What should a backup installer refuse to do?
- Sell a battery as backup without confirming the inverter can island the home.
- Leave the essential circuits undecided until installation day.
- Promise a number of hours of backup without knowing which appliances will run.
- Wire a generator into the switchboard without the correct changeover equipment.
- Skip the inspection and Certificate of Electrical Safety after switchboard changes.
Next step: describe the outage you want to ride out
When you ask about backup power for your home, include:
- The appliances you want to keep running, and roughly how many hours you want them to last.
- Whether anything in the house is medical or life support equipment.
- The brand and model of any existing inverter and battery, with a photo of each label.
- A photo of your switchboard with the cover open, and your suburb.
Frequently asked questions
- Can I get backup power from solar panels without a battery?
Not with a standard grid connected system, because it switches off when the grid fails. Some inverters offer a limited daytime outlet, but it only works while the sun is up and supplies very little. For lights and a fridge through an evening outage you need a battery set up for backup.
- Will my whole house run on battery backup during an outage?
Usually not. Most backup systems supply a selected set of circuits so the battery lasts longer. Whole home backup needs a larger battery and inverter and more switchboard work, and heavy loads such as ovens, heaters and electric hot water drain a battery fast. Decide what you actually need before asking for whole home coverage.
- How long will a battery keep my fridge and lights going?
It depends on the battery's usable capacity, how much charge is left when the outage starts, and what is running. A provider can estimate it once you list the appliances on the backup circuits. If panels can recharge the battery while the house is islanded, a daytime outage is easier to ride out than one that starts at night.
- Is a portable generator a better option than battery backup?
A generator can run for as long as there is fuel, which suits long outages, but it is noisy, needs servicing and must never be run indoors. Connecting one to the house wiring needs a licensed electrician and proper changeover equipment. Some households use both: a battery for short outages and a generator for long ones.
- Can an existing battery be converted to provide backup?
Sometimes. If the inverter supports backup, the job may only need a backup circuits board and some switchboard changes. If it does not, the inverter may need replacing or a separate backup unit added. Send the battery and inverter models so a provider can check the manufacturer's specifications.