Batteries are not free money. Here's when they make sense in 2026, and when you're better off exporting everything.
Adding a battery to a solar install increases the upfront cost and typically lifts self-use from around 45% to around 75% of generation. A battery earns its keep fastest on cheap-rate overnight import tariffs and modest SEG export rates — the case weakens if you're already on a high-paying export tariff, since the spread between import and export narrows.