Three policy moves landed within weeks of each other this October, in three different markets, and they point the same way: residential storage is leaving the phase where subsidies chased volume and entering one where regulation defines what counts as an acceptable product.

Australia: past half a million, growth now comes from retrofits

Australia’s Cheaper Home Batteries Program opened on 1 July 2025 and passed 500,000 installations by mid-August 2026 — roughly fourteen months. The number of accredited installers has doubled to 8,846 over the same period. The Clean Energy Council puts first-half 2026 additions at 276,011 systems, up 52% on the preceding six months.

The more revealing number is the attachment ratio. For every 100 rooftop PV systems installed in the first half of 2026, 153 batteries went in. A ratio above 100% means the growth engine is no longer households buying solar and adding a battery in the same transaction; it is existing solar owners coming back to retrofit storage. That changes the project profile — retrofits bring grid-connection questions, inverter compatibility checks and physical siting constraints that new-build jobs do not.

The subsidy is tapering at the same time. Funding was lifted from A$2.3 billion to A$7.2 billion over four years in December 2025, but from 1 May 2026 the certificate multiplier fell from 8.4 to 6.8 per kWh and became tiered: full value on the first 14 kWh, 60% from 14.1 to 28 kWh, 15% from 28.1 to 50 kWh, nothing above 50 kWh. The next step-down is set for 1 January 2027, then every six months through 2030.

Poland sets a capacity floor, the UK sets locations

Poland’s Ministry of Climate and Environment opened a PLN 1 billion (about US$258 million) home storage scheme on 20 October, running until 1 October 2027 or until the budget runs out. Two conditions shape the product: the battery must be at least 10 kWh nominal, and its capacity must reach at least 2 kWh for every kWp of the accompanying PV array. Grants cover up to 30% of eligible costs, capped at PLN 800/kWh, with a ceiling of PLN 16,000 for net-billing prosumers and PLN 8,000 for those on net metering; total support per supply point is capped at PLN 19,000. Eligible systems must also include an energy management system and island-mode capability. The ministry counts roughly 150,000 residential systems as of June 2026, up from just over 10,000 in the first quarter of 2024, and is targeting more than 200,000 by the end of 2027.

In the UK, the six-month transition to BS 7671:2018+A4:2026 ended on 15 October. The amendment adds Chapter 57, the first dedicated section for fixed battery installations, and requires domestic work to comply with PAS 63100:2024. New systems can no longer go into lofts or roof spaces, bedrooms, escape routes such as hallways and stairwells, or basements without direct external access. Outdoor units need one metre of clearance from doors, windows and ventilation openings, and two metres from stored flammables. Existing systems are not made non-compliant retroactively, but any extension or alteration falls under the new rules.

What this means for procurement

• Size to the subsidy structure, not to cell cost. Poland starts at 10 kWh; Australia’s full rate stops at 14 kWh. Capacity architecture should follow the policy, not the bill of materials.
• Treat installability as part of the deliverable. After the UK change, distributors need siting guidance, ventilation and fire-separation drawings alongside the datasheet.
• Backup and EMS are becoming gate conditions. Poland mandates island capability; Australia ties eligibility to VPP readiness.
• Outdoor and garage siting raises the weight of thermal design. Check cycle-life figures under high ambient temperatures, not only at a 25°C reference point.

The incentive window is still open, but the era of selling whatever happens to be in stock is over. The useful question for a buyer now is whether a supplier can hand over three things at once: the product, the compliance file and a workable installation plan.