A generator inlet is a weatherproof socket on an outside wall that a portable generator plugs into, and a changeover switch at the switchboard disconnects your home from the grid before connecting selected circuits to the generator. Installed by a licensed electrician, the pair is the safe way to keep the fridge, lights and internet running from a generator during a long suburban blackout. It is not a DIY project, and there is no safe shortcut that involves plugging a generator into a power point.

Why back-feeding is dangerous

Back-feeding means pushing generator power into your home's wiring through a power point, usually with a home-made lead that has a plug on each end. It is one of the most dangerous things a household can do during an outage:

• Risk to line workers. Power can flow back through your meter into the street network, where a transformer can step it up to a much higher voltage. Crews repairing lines they believe are dead can be seriously injured or killed.
• Exposed live pins. A lead with a plug on both ends has live, bare pins on the loose end whenever the other end is connected.
• Overloaded wiring and fire. Household circuits and their protection are not designed to be fed backwards from a socket.
• Damage when the grid returns. If your home is still connected to the network when power is restored, grid supply and generator supply collide, which can destroy the generator and damage appliances.

A properly installed changeover switch is designed so that your home cannot be connected to the grid and the generator at the same time, which removes the main hazards above. Keep in mind what it does not do: it does not start the generator for you, and there is a gap between the blackout and the moment you switch over, so computers and modems will restart. If uninterrupted internet matters, a small uninterruptible power supply for the modem bridges that gap.

What an inlet and changeover switch can power

What runs depends on the generator's continuous rating and on which circuits the electrician connects. Most suburban installations connect a set of essential circuits rather than the whole house. As a rough guide:

Motors and compressors in fridges, pumps and air-conditioners draw several times their running current as they start, so size the generator with headroom. Inverter-type generators give a steadier output that suits electronics such as computers and modems. Ask the electrician to list exactly which circuits the changeover will supply and to label them clearly on the switchboard.

How solar and batteries fit in

A standard grid-connected solar inverter shuts down when the grid fails, as its anti-islanding protection requires, so your panels will not help while the generator runs. That is normal. The electrician also needs to decide how the solar inverter is treated during generator operation, because an inverter that mistakes generator supply for the grid could try to export into the generator.

If you have a battery, the design needs even more care. Some hybrid inverters have a dedicated generator input that can charge the battery; others must be kept entirely separate from a generator. Never connect a generator to a battery system's backup output unless the manufacturer's documentation specifically allows it. Our guide to the best solar inverters covers how backup features differ between models.

Installation: what to expect and what to ask

1. A licensed electrician inspects your switchboard and helps you choose the essential circuits.
2. An outdoor-rated inlet is fitted on an outside wall where the generator can run in open air, away from windows, doors and vents.
3. The changeover switch is installed at the switchboard, sometimes with a small sub-board for the essential circuits.
4. The work is tested and labelled, and you receive a Certificate of Compliance for Electrical Work.
5. The electrician walks you through the switching sequence, step by step, so you can follow it in the dark.

Questions to raise: which generator size and lead suit the inlet, whether generator-fed circuits keep safety switch protection, and whether an old switchboard needs upgrading first. The market lists a Generator Inlet & Changeover Switch from $990 and a Switchboard Upgrade from $1,490, both indicative. Always run the generator outdoors: its exhaust contains carbon monoxide, which can kill in a garage or enclosed carport even with a door open.

Generator inlet or home battery?

For a suburban home that sees occasional short outages, a battery offers daily savings plus backup. Where outages can last days, a generator's runtime is hard to beat, and some households choose both. The federal Cheaper Home Batteries Program takes roughly 30% off an eligible battery installed with solar; its value steps down every 1 January and 1 July, so confirm current figures before you sign. If you are unsure whether an existing battery offers backup, our explainer on hybrid and string inverters is a good starting point.

Next steps

Decide which circuits you truly need during an outage and how long outages tend to last in your street, then compare an inlet, a battery with backup and a combined design. Indicative prices for generator inlets, backup circuits and blackout protection packages are on the energy market page, confirmed after a switchboard inspection. To have the options assessed against your existing solar and switchboard, request a free assessment from Blue Energy Solar.

Frequently asked questions

Can a portable power station plug into a generator inlet instead?

Only if a licensed electrician confirms it is suitable. The inlet and changeover are designed around a generator's plug type and output, and many portable power stations have a lower output or are not designed to supply switchboard circuits. Check the unit's manual and ask the electrician before trying it. Never make up adaptors or special leads to connect any power source to your wiring.

Can a generator inlet be added to a home that already has a battery?

Often, but it needs careful design so the grid, the generator and the battery inverter never conflict. Some hybrid inverters accept a generator input and can use it to recharge the battery, while others must be isolated whenever the generator runs. Ask for the inverter manufacturer's compatibility requirements to be checked before the work is quoted, and make sure the switching sequence is written down.

How often should I run the generator between blackouts?

Follow the manufacturer's schedule, but a common approach is a short test run under some load every month or two. Use fresh fuel or a fuel stabiliser, since stored petrol deteriorates, and check the oil and air filter. A test run is also a good moment to practise the changeover sequence, in daylight and with the electrician's written instructions beside you.