Updated for 2026
"It depends" is true and useless. So here's the dependence, spelled out: a battery is worth it when the gap between what you pay for evening electricity and what exporting would have earned you is wide enough, often enough, to repay the installed cost before the warranty runs out. In WA right now, that gap is unusually wide — which is why the question has stopped being rhetorical.
BillWise analyses bills; we don't sell batteries. Every figure below is the published rate or an indicative estimate — installers quote actual prices.
2cper kWh off-peak (DEBS)
Under WA's Distributed Energy Buyback Scheme, exports earn 10c during the 3pm–9pm peak — but most of your export happens in the middle of the day, at the off-peak rate.
33.26cper kWh (Synergy A1)
Every kilowatt-hour you buy back in the evening costs the full usage rate — more than ten times the off-peak buyback.
~31cper stored kWh
Give up a couple of cents of export income, avoid a usage charge more than ten times larger. That spread is the battery's entire business case — everything else is multiplication.
(Why is the buyback so low when power is expensive? Because midday WA is drowning in solar — everyone's panels peak together. That's not a scandal; it's the physics of a million rooftops. It's also precisely the market signal that says storage, not more export.)
8–12 year payback
at our two reference Perth profiles, on today's rates and rebates
Independence means saying this part out loud.
Two things can improve the base arithmetic, with eyes open: VPP participation — required for the WA rebate anyway — pays you for grid access to your battery; treat the income as a bonus, not a pillar. And time-of-use plans can widen the effective spread for households whose usage suits them — the calculator models this rather than us generalising here.
A solar battery in WA is worth it more often than it was three years ago — wider spread, stacked rebates, cheaper storage — but it is still a per-household verdict, and the inputs are sitting on your last few Synergy bills. Run them. If the numbers work, get quotes with the sizing the calculator suggests. If they don't, you've spent ten minutes to save five figures — the best return on this page.
Too small a battery leaves you buying grid power at 33c/kWh. Too large and you're paying for storage you never use. Here's how to calculate the right battery size for your household.
Battery prices have fallen significantly, but so have export rates. Here's a straightforward analysis of home battery ROI in Perth across different tariffs, system configurations, and usage scenarios.
The WA Battery Scheme gives eligible Synergy customers up to $1,300 off a home battery. Here's exactly who qualifies, how the application works step by step, and what to do if your claim stalls.
Virtual power plants (VPPs) let solar battery owners earn money by sharing stored energy with the grid. Here's the honest picture of what's available in Perth in 2026, what you actually earn, and whether WA is ready.
