Battery Installation rules overview
This is an introductory overview the Australian Standards AS 5139 which loosely covers home solar batteries. It is not intended to be a complete guide to the standards so do not rely solely on this document to determine your compliance. Please don’t hesitate to contact us if you require any assistance (1800 82 66 76).
Adding battery storage to home solar systems is an increasingly popular choice with a plethora of options for both full off-grid systems, as well as grid-connected systems popping up for consumers.
An important factor in considering adding batteries, especially if you’re going to install them yourself, is to ensure that their installation complies with the Australian Standards (AS 5139) which were fairly recently updated in October 2019.
The AS 5139 standard applies to all new or modified systems with at least 12v and 1kWh capacity (which puts the minimum battery that they would apply to to be a 12v, 90Ah battery ) installed on a home, garage, shed, or commercial property. But doesn’t cover caravans, UPS devices, or telecommunication applications.
The standard sets up three different categories for batteries. Category 1 covers Clean Energy Council (CEC) approved “pre-assembled integrated battery energy storage systems”, which essentially is a CEC approved lithium battery systems with internal fuses and an inverter such as the Tesla Powerwall 2. These have the fewest rules and are the easiest to install, but with the drawback of offering the least amount of customisation. The rules here relate mostly to location, testing, and documentation.
Category 2 covers CEC approved “pre-assembled battery systems”, which is a CEC approved lithium battery with internal fuses but without an inverter which has to be installed separately. The added complexity means that it has a few more pages of rules for installation. These have all the same rules Category 1 but also require specific requirements for wiring, fusing, earthing, and that kind of thing
Category 3 covers all non CEC approved batteries which includes lithium batteries that haven’t been approved by the CEC, as well as lead-acid batteries and any other strange battery you’ve had your eye on. Category 3 batteries must meet all the requirements as 2 and 1, but also have to meet rules on ventilation, enclosure design, voltage drop, and arcing.
The rules for installing a new battery system have some pretty important limits on location, with the general vibe being an external house wall or inside a garage being ideal locations.
The standards prohibit batteries being installed in a “habitable room” (basically anything inside), or anywhere obviously stupid (wall cavities, ceiling spaces etc) or anywhere that might be a dangerous if something goes wrong (eg evacuation route, or near flammable material).
Batteries can also not be installed close to windows or doors, or other electronic appliances such as hot water units or air conditioners.
If the battery is installed on the other side of a habitable room then it needs to have appropriate shielding between it and the room.
Finally category 3 batteries have a few more limits, and in particular category 3 lithium batteries or high voltage battery systems have to be installed in a structure detached from the house.
The “good” news if you’ve got a system that pre-dates the new rules coming in is that they don’t apply retrospectively so you aren’t legally required to do anything to your system. That being said, the rules are very much there for your safety, so if there’s a glaring anomaly between your system and the updated rules, it is certainly worth considering modifying things to be more complaint.
But the key thing to note is that any upgrade or modification to an existing system triggers a requirement that the whole system meet the new standards.
And in addition there are some complex rules regarding the safety equipment required to be worn for inspection and maintenance of systems, especially older lead-acid ones, but the specific rules can only be accessed by purchasing a copy of the Standards, so it is very difficult for a normal home user to know exactly what rules they are required to follow, especially when following the rules is often a requirement for the warranty.
We do provide an inspection and maintenance service for solar systems and batteries, and the Tasmanian Government does recommend it be carried out every year or two, but please don’t hesitate to give us a call if you have any questions.
The battery rules may sound complicated, but as a one off consideration, it is worth getting everything right so you can enjoy your system safely and worry free for years to come.