Every storm season, thousands of Queensland homes lose power, sometimes for days. If you rely on a fridge full of food, a water pump, a home business or medical equipment, a backup power plan is worth thinking about before the next storm, not during it.

Here's how to work out what you need, the main options, and the safety rules that matter.

Start with what you need to power

Before you buy anything, list what has to keep running. Typically:

  • Fridge and freezer
  • Some lights
  • Phone and internet (modem and chargers)
  • Fans, and maybe one air-conditioner
  • Water or sewage pumps on rural or acreage blocks
  • Medical equipment, if anyone in the house depends on it
  • Security or garage door

Add up the running watts and allow for start-up surges (fridges and pumps draw several times their running load when they start). An electrician can help you work this out. Powering a few essential circuits is far cheaper than powering the whole house.

If someone in your home relies on life-support equipment, register with your electricity retailer. You'll get notice of planned outages, but you still need a backup plan for unplanned ones.

Why solar panels alone won't help

This catches a lot of people out. Standard grid-connected solar switches off in a blackout. Australian Standard AS/NZS 4777 requires inverters to stop exporting when the grid goes down (called anti-islanding), so they don't send power down lines that line workers think are dead.

You only keep power during an outage if you have a battery system with backup or emergency power supply (EPS) capability, and it's wired to supply your essential circuits. Not every battery does this, so ask specifically.

The options

Portable generators (petrol, diesel or LPG)

  • Pros: The cheapest option. Can run a fridge, lights and chargers. Easy to take elsewhere.
  • Cons: Noisy, need fuel and regular running to stay reliable, and must be run outdoors well away from doors and windows because of carbon monoxide.
  • How to use safely: Either plug appliances directly into the generator with heavy-duty outdoor leads, or have an electrician install a generator inlet and changeover switch so the generator can feed selected circuits.

An inverter generator is the better choice for electronics because it produces cleaner power and runs quieter.

Home batteries

  • Pros: Silent, no fuel, switches over automatically (with a backup-capable system), and charges from your solar panels. Saves money every day, not just in a blackout.
  • Cons: Expensive, though the federal Cheaper Home Batteries Program has reduced the upfront cost. Capacity is limited, so in a long, cloudy outage it may run flat.
  • What to check: That the system supports backup or EPS, which circuits are backed up, and how long the battery will last on your essential loads.

Batteries and generators can work together. Some hybrid inverters accept a generator input to recharge the battery during a long outage.

Permanently installed standby generators

  • Pros: Start automatically when the power fails and can run the whole house.
  • Cons: Expensive to buy and install, need fuel storage (diesel or LPG) and regular servicing.
  • Usually suits: Acreage homes with pumps, home businesses, or people with critical medical needs.

Diesel or petrol?

Diesel engines are generally more durable and fuel-efficient for long running, but cost more upfront. Petrol units are cheaper and lighter but fuel goes stale if stored. How long any generator runs depends on its tank size and the load, not the fuel type. Check the manufacturer's run-time at the load you expect.

This is the most important section in the post.

  • Never plug a generator into a power point to feed the house. A "backfeed" lead can electrocute you, your family, or a line worker restoring power down the street, and it's illegal.
  • Any connection to your house wiring must go through a changeover switch (manual or automatic) installed by a licensed electrician to AS/NZS 3000 and AS/NZS 3010. The switch disconnects your house from the grid before the generator supplies it.
  • An automatic transfer switch (ATS) does this by itself and can start a standby generator automatically. A manual changeover switch is cheaper and fine for portable generators.
  • Your electricity meter doesn't do any of this. Smart meters belong to your metering provider and measure usage. They don't switch circuits or start generators.

Practical tips

  • Choose essential circuits carefully. Your electrician can wire a separate essential-circuits board for the fridge, lights and power points you nominate.
  • Test it. Run the generator monthly and test the changeover at least a couple of times a year. A generator that hasn't run since last summer often won't start when you need it.
  • Store fuel safely in approved containers, away from the house, and rotate it.
  • Keep the basics anyway. Torches, a battery radio, power banks, a cooler and ice will get you through a short outage cheaply.
  • Building new? Ask your electrician now about a generator inlet, an essential-circuits board or a battery-ready switchboard. It's much cheaper to do during the build than to retrofit.

A bit of planning means the next storm is an inconvenience rather than a crisis. Get a licensed electrician involved early, and never take a shortcut on the connection.