More than a quarter of a million units were installed across the country in the first nine months, adding around 7.7 gigawatt-hours of storage.That's equivalent to about 40 of the big batteries Elon Musk built in South Australia.To ensure the program does not run out of money prematurely and is distributed evenly, changes to how the rebate is applied take effect today.Starting today, the federal home battery subsidy will decline more quickly over time and be applied on a tiered basis by size.Until today, the size of the discount has been directly related to the battery's capacity.Now, to curb the rush toward ever-bigger systems, it tapers off after 14 kilowatt-hours as follows:It's all a bit complicated, but the government has a handy calculator here."The .. changes were announced on 13 December 2025 and are aimed at ensuring the program can be sustained to 2030 to deliver around 40 gigawatt hours of storage capacity," a spokesperson from the Clean Energy Regulator said."These changes ensure the discount remains at 30 per cent for a range of battery sizes and aligns with falling battery costs over time."Just like rooftop solar systems, household batteries are treated like small power plants and, depending on capacity, are issued "vouchers"