solar power your home during a blackout?
Australia's love affair with rooftop solar has reshaped the national energy landscape, with more than three million households now generating their own electricity. Yet every summer, when severe thunderstorms lash Melbourne, bushfires threaten the fringes of Sydney, or ex-tropical cyclones cut supply across regional Queensland, homeowners are reminded that grid power can vanish without warning. The question of whether a solar array can keep the lights on during a blackout has therefore shifted from a niche curiosity to a mainstream concern across the country.
The short answer depends entirely on the type of system installed. A standard grid-tied PV array with no battery storage will switch off the moment the grid goes down, leaving the panels idle even while the sun blazes overhead. To gain true energy independence during an outage, a household needs additional hardware, careful system design, and a working knowledge of how Australian standards govern the behaviour of solar equipment.
Why standard solar systems go dark in an outage
The reason a typical rooftop solar installation shuts down during a blackout is a safety feature called anti-islanding protection. Australian Standard AS/NZS 4777.2 requires every grid-connected inverter to detect the loss of grid voltage and cease exporting power within two seconds. The rule exists to protect lineworkers repairing damaged infrastructure, but for homeowners it means that a perfectly functional solar array becomes a silent observer during an outage.
Network operators such as Ausgrid in New South Wales, CitiPower in Melbourne, and SA Power Networks reinforce this requirement through their connection agreements. The Australian Energy Market Operator also expects distributed energy resources to behave this way, so even if a homeowner wanted their panels to keep running during a blackout, the inverter would override the attempt. This regulatory framework is non-negotiable, and it explains why so many households in Adelaide, Brisbane, and Perth discovered during the September 2016 storm that their systems went dark along with everyone else.
This behaviour surprises many homeowners, who reasonably assume that sunshine on their panels should mean free power during an outage. The reality is that the inverter cannot distinguish between a genuine grid failure and a temporary disturbance, and it must err on the side of caution. Until recently, there was no practical way around this limitation, but advances in hybrid inverter technology and battery integration are beginning to change what is possible.
How battery storage changes the equation
Adding a battery changes the dynamic significantly. When the grid drops out, a hybrid inverter with battery storage can island the home, drawing on stored energy to run selected appliances while the panels continue to recharge the battery during daylight hours. The capacity of the battery determines how long the household can operate before the reserve is exhausted, which is why comparing different chemistries matters so much for Australian conditions.
The trade-off between lithium-ion versus lead-acid batteries comes down to usable capacity, depth of discharge, cycle life, and tolerance for the heat found in a tin roof on a forty-degree day in Dubbo or Mildura. Lithium-ion systems typically allow deeper discharges and last longer in cycled applications, while lead-acid remains a lower-upfront option for sheds and weekenders. Households sizing a system for blackout resilience usually need at least 10 to 14 kilowatt-hours of storage to cover evening essentials like refrigeration, lighting, and internet routers through a typical overnight outage.
For households in remote areas of South Australia or Tasmania, where grid outages can last for days following severe weather, larger battery banks of 20 kilowatt-hours or more may be warranted. Urban households in Sydney or Brisbane might get by with smaller systems if the goal is simply to ride out a few hours of darkness until the network is restored. Either way, the key is to match storage capacity to the realistic duration of outages experienced in the local area, rather than sizing purely on daily energy consumption.
Inverters that keep critical loads running
Not every inverter is capable of forming a local grid during a blackout. Traditional string inverters need a stable reference voltage from the network to operate, so they shut down when the grid disappears. Hybrid inverters can establish their own voltage and frequency reference, allowing them to continue running a designated set of circuits when the wider network is dark.
SMA has long offered solutions tailored to this exact scenario. The Sunny Boy range includes models with a built-in backup function that can supply a small dedicated load output during outages, while the Sunny Island battery inverter is designed for off-grid and backup applications in remote properties and edge-of-grid homes across Western Australia and the Northern Territory. For households seeking a whole-home backup solution, a Sunny Boy Smart Energy inverter paired with a compatible battery can automatically island the dwelling within milliseconds of a grid failure, keeping fridges, freezers, and medical equipment running without the homeowner needing to switch anything manually.
Planning a blackout-ready system for Australian conditions
Designing a system for true resilience starts with identifying the loads that matter most. For many Australian households, this means the refrigerator, a few lights, the Wi-Fi router, a phone charger, and perhaps a gas hot water system or a bore pump. Medical devices such as CPAP machines add another layer of urgency, particularly in rural communities where the nearest hospital is hours away. Working through this list with an accredited installer helps determine the battery capacity and inverter rating required.
Local climate risks should also shape the design. Homes in cyclone-prone Townsville and Cairns benefit from robustly mounted panels and weather-sealed battery enclosures. Bushfire-prone suburbs on Sydney's urban-rural fringe may need careful siting of external battery units, with many newer systems offering wall-mounted indoor installations. Coastal homes in Fremantle or the Mornington Peninsula should specify corrosion-resistant fittings. Across all regions, the Clean Energy Council's guidelines and accredited installer network provide a framework for safe, compliant installations.
Costs, rebates and the payback question
A battery-ready system typically adds between $8,000 and $18,000 to a standard solar installation, depending on capacity, brand, and whether the inverter is being upgraded at the same time. Federal incentives such as the Small-scale Renewable Energy Scheme reduce the upfront cost through small-scale technology certificates, while the Victorian Solar Homes Program and similar state schemes in Queensland and South Australia have periodically offered additional rebates for battery storage. The economics improve markedly for households that already have high daytime consumption or that face expensive time-of-use tariffs.
A well-designed battery system can also store surplus solar that would otherwise be exported to the grid for a feed-in tariff of around five to seven cents per kilowatt-hour. Under net metering explained: how you get paid for extra solar power, the value of that stored energy is effectively shifted to the evening peak, when imported electricity costs thirty to forty cents per kilowatt-hour in many Australian capital cities. The simple payback for a battery in this configuration often lands between eight and twelve years, with the system continuing to deliver value for many years beyond that.
Talk to your local SMA installer about tailoring a backup solution that matches your home, your region, and the way your family actually uses energy. Explore the full range of SMA inverters and battery-compatible systems on Solar is Future, where detailed guides, product specifications, and Australian case studies will help you decide whether a blackout-ready solar setup is the right investment for your household.