Blackout Ready Home: Batteries, Generators and What Actually Keeps the Fridge Running

What actually keeps the fridge running when a Sydney blackout hits? Only a backup source that is properly wired to carry your essential circuits: a home battery installed with backup capability, or a generator connected through a transfer switch at your switchboard. Solar panels on their own shut down with the grid, and a portable generator with nowhere legal to plug in will leave you standing in the dark holding an extension lead.

⚡ Quick Answers: blackout ready homes

• Does solar keep the power on in a blackout? Not by itself. Standard grid-connected inverters switch off when the grid fails. You need a battery with dedicated backup circuits wired at the switchboard.
• Will a home battery run the whole house? Usually only nominated essential circuits, and only until the stored energy runs out. Whole-home battery backup needs serious sizing.
• What is the fastest automatic option? A standby generator with an automatic transfer switch. A Generac Guardian restores nominated circuits in 45 to 75 seconds without you touching anything.
• Can I plug a portable generator into a power point? No. That is backfeeding, it is illegal, and it can electrocute the crews working to restore your street. Portable generators need a changeover switch and inlet installed by an electrician.
• What does a UPS actually do? It bridges short interruptions for sensitive gear like modems, computers and CPAP machines. It is not a house backup.
• Who installs backup power? Anything wired at the switchboard is licensed electrical work, and generator connections need network approval, which is where a Level 2 electrician comes in.

1. Start with the fridge: work out your essential circuits

Being blackout ready is not about powering everything. It is about keeping a short list alive: the fridge and freezer, a few lights, the modem and phones, the garage door, and any medical equipment. For most Sydney homes that list draws far less power than the whole house, which changes what you need to buy.

Walk the house and write the list down before you compare hardware. Our generator load calculator walkthrough shows how to turn that list into a number in about two minutes, and the same thinking applies to sizing a battery.

2. Home batteries: backup is a setup, not a given

Plenty of Sydney homes have paid for a battery and still lost power in a storm, because backup was never configured. For a battery to carry you through a blackout, your electrician needs to wire nominated backup circuits at the switchboard and the system needs an inverter that can run off grid. If the installer never set that up, the battery politely shuts down with the rest of the street.

Done properly, a battery is silent, instant and recharges from your solar the next morning. The trade-offs are capacity and cost: a typical battery holds enough for the essentials overnight, not for days of ducted air conditioning. Our guide to solar battery storage compliance in NSW covers the rules that shape where and how batteries are installed.

3. Standby generators: the set-and-forget option

A standby generator sits outside like an air conditioner unit, runs on natural gas or LPG, and pairs with an automatic transfer switch that senses the outage, starts the unit and switches your nominated circuits across on its own. With a Generac Guardian installation that whole sequence takes 45 to 75 seconds, and it runs for as long as the gas supply lasts, which is what separates it from a battery in a multi-day storm event.

It is the most expensive path, with installed packages typically starting in the low five figures depending on size and site. Read what happens on a Generac install day to see what the money buys.

4. Portable generators: legal only with the right wiring

A portable generator can absolutely keep a house going, but only through an inlet point and changeover switch installed at the switchboard. The changeover physically separates your home from the grid before the generator can feed it, which protects line crews and your own wiring. The second it becomes a lead through the kitchen window into a power point, you are backfeeding, and that is both illegal and genuinely dangerous.

Our comparison of standby versus portable generators covers the practical differences, and this guide to generator transfer switches explains the switch options. Remember a portable unit is manual: someone has to be home, wheel it out, fuel it and start it, usually in the rain.

5. A UPS bridges the gap for the small stuff

An uninterruptible power supply is a battery in a box that keeps a modem, computer or medical device running through short interruptions and gives you time to shut things down or switch to another source. If someone in your home relies on powered medical equipment, pair a UPS with an automatic option and read our guide to backup power for medical equipment at home.

6. Which one fits your home

If your outages are rare and short, a battery you already wanted for bill reasons, configured with backup circuits, is usually the smartest spend. If you are in a tree-heavy suburb where storms take the street out for days, gas-fed standby generation is the only option that does not run out overnight. If the budget is tight, an inlet and changeover switch for a portable unit is the cheapest legal path to keeping the fridge cold. And it is worth knowing whether a brownout or a blackout is what you are actually experiencing, because they call for different responses.

Whichever network you are on shapes approvals and outage patterns, and you can check your network area in seconds with our postcode checker. For the bigger picture on who fixes what after a storm, see storm damage triage: what is Ausgrid's problem and what is yours.

Why it's Level 2 ASP work

Every one of these options ends at your switchboard, and the connection work there is licensed electrical work. Generator setups also need network approval under the Service and Installation Rules of NSW, with changeover gear that makes backfeeding impossible and correct labelling at the board. Where the job touches your service line, metering or supply capacity, it moves into Level 2 ASP territory, and an ageing board may need a switchboard upgrade before it can host a transfer switch at all. See our guide to switchboard upgrades for generators.

How High Demand Electrical helps

We install and connect the full spread: Generac Guardian standby systems with automatic transfer switches, inlet and changeover setups for portable units, and the switchboard work that battery backup circuits need. Because we are Level 2 accredited, we handle the network approvals and any supply upgrade in the same job rather than handing you between contractors. We start with your essential circuits list and size from there, so you are not paying for capacity you will never use.

Blackout backup FAQs (Sydney)

How long will a home battery last in a blackout?

A typical residential battery carries essential circuits through an evening and overnight. Heavy loads like ovens, pool pumps and air conditioning drain it quickly, which is why backup circuits are chosen carefully at install time.

Do I need council approval for a standby generator?

Placement, noise and gas connection all have rules attached. Our guide to home generator council approval in NSW walks through when approval comes into play.

What happens to my solar during a blackout?

A grid-connected inverter without a battery shuts down automatically so it cannot energise the street while crews are working. It restarts on its own once supply returns.

Is a generator or a battery better for medical equipment?

Automatic restoration matters more than the fuel source. An automatic transfer switch or a battery with configured backup circuits both work, ideally with a UPS bridging the changeover seconds.

Get a generator installation quote or talk through battery backup wiring with our team. Call 0402 559 777. Every backup power job starts with a site assessment so scope and pricing are confirmed before any work begins.