Australia Has Installed Half a Million Batteries. Who’s Checking They’re Safe?

Peter Hannam quoted me in RenewEconomy on Friday, saying I expect there are hundreds of thousands of solar and battery systems out there that aren’t optimally installed or configured, some of them carrying real potential for dangerous outcomes.

He ran that alongside what Chris Bowen had told parliament two days earlier, when Dan Tehan asked whether the minister could guarantee every subsidised battery had been installed safely and to standard. Bowen’s answer was that the Small-scale Renewable Energy Scheme is “one of the world’s most rigorous schemes for compliance,” and that it had received 315 complaints against 800,000 installations in the past year. That’s 0.04 per cent.

I want to show my working because “hundreds of thousands” isn’t a number I pulled out of my arse to sound alarming. If anything, it’s conservative compared to what you get from multiplying out the Clean Energy Regulator’s own inspection data.

A complaint rate measures complaints, not compliance

Bowen’s 0.04% tells you how many people rang up to complain. I’m not sure about you, but one of the last places I’m gonna call if I fall out with a solar retailer is the Clean Energy Regulator. That number tells you nothing about how many systems are broken, badly installed, poorly designed, misconfigured, or underperforming.

Luckily, the regulator has a second number. The CER conducts its own physical inspections of battery installations, separate from the complaints line, and publishes the results. As of 30 June 2026, it had inspected 3,425 systems and checked over 285,000 individual items against them. The result: 62.28 per cent of installations were rated substandard, which the CER defines as breaching at least one clause of an Australian Standard or industry guideline while still being safe to leave running, and a further 0.76 per cent were rated outright unsafe.

To be fair to the installers, the biggest share of the substandard findings is labelling: missing warning labels at the switchboard, backed-up circuits not marked, no emergency services sticker on the meter box. The wiring faults, misconfigured RCDs, cables without proper mechanical or fire protection, and undersized overcurrent protection are the smaller share.

Doing the maths Bowen didn’t

Bowen told the House that more than 530,000 batteries have gone in under the Cheaper Home Batteries program. Apply the regulator’s own inspection rate to that population and you get roughly 330,000 systems that are technically non-compliant and around 4,000 that are unsafe.

That’s where “hundreds of thousands” comes from: the CER’s own audit percentage, multiplied by the CER’s own installation count.

It indicates there are thousands of systems the regulator would classify as an immediate or developing risk to people or property, sitting in Australian homes right now.

The stuff that will never even get inspected

The CER’s substandard and unsafe categories cover compliance with wiring rules. They say nothing about the much bigger bucket of batteries that are technically safe, technically compliant, and still doing a mediocre job for the person who paid for them. Some examples off the top of my head, based on what folks tell me every week:

• Undersized inverters, so large loads always pull from the grid.
• Current transformers in the wrong place, so the battery isn’t offsetting the loads it’s supposed to.
• Batteries stuck in full sun or a hot garage, derating in the short term and losing capacity for good over a few summers.
• Batteries with no heater crippled on a cold Adelaide or Canberra morning in winter.
• No configuration to import cheap or free grid power on a low solar day and through winter.
• No export is configured for big batteries, even though the batteries’ spare capacity could feed the grid for cash instead of sitting idle.
• Big loads like hot water left to drain the battery instead of being scheduled around it.
• An EV charger that can’t talk to the battery, or is not wired upstream of it, draining the battery instead of using a cheap EV tariff.
• Reserve set too high, so a chunk of paid-for capacity just sits idle.
• No enrolment in a battery-friendly plan, which is pure lost revenue every single day.
• Warranty degradation that will bite in a few years on the cheaper cells, which the owner has absolutely no way of monitoring.

Every one of those is a battery underperforming for a customer. Multiply that across half a million systems, and the gap between what the government thinks it delivered and what actually got installed is enormous.

What needs to happen

I don’t want a Senate inquiry that files a report in eighteen months. I want a $300 inspection, funded by a subsidy that paid up to $18,000 per system when the scheme launched and still pays several thousand dollars per system today.

As a priority, I want to catch that unsafe 0.76 per cent before it becomes a tragedy, and also catch poor design and configuration, so that homeowners get the savings they deserve and Aussie taxpayers get maximum value from their bloody generous $7 billion investment in battery rebates.