25-year real cost, not year-one marketing

Stop the battery spin.See what actually pays off.

A side-by-side built to run the full 25-year lifecycle: STCs and the federal battery rebate, cleaning, two inverter replacements, two battery replacements at full price, battery degradation to end-of-warranty capacity, and the daily supply charge everyone keeps paying regardless of which option they choose.

Independently modelled using published 2026 Australian market data — Canstar, the Clean Energy Regulator, the Cheaper Home Batteries Program, and SolarCloud's own quick price comparison. Not financial advice — see assumptions below.

Quarterly bill

Avg. Australian home ≈ $500/qtr (Canstar)

Solar system size

Panel quality

Battery brand

Battery size (per unit)

How many batteries

Inverter warranty offered

Affects replacement timing on the chart

Advanced assumptions (usage rate, supply charge, offsets, cleaning) — edit if you know your own numbers

Usage rate ($/kWh)

Feed-in tariff ($/kWh)

Daily supply charge ($/day)

Self-consumption, solar-only (%)

Extra self-consumption from battery (pts)

Cleaning cost per visit ($)

STC value ($/kW)

Side-by-side · 25-year term

What each option actually costs and saves

Figures are nominal (today's dollars, no inflation applied to bills). "Total cost" and "net position" now include the daily supply charge for Option A, since export credit can't touch it — and exclude it for SolarCloud, since their credit already covers it. See the note below the cards.

Batteries aren't recycled, they're replaced — full price, at year 10, again at year 20, and a third time if you stretch it to 30.
We all hate high energy bills. But is a depreciating battery really the answer?
No spin either way — the facts are in the numbers below, not a sales brochure.

Signature check · degradation

Battery capacity over 25 years

Warranties guarantee a floor, not a cliff-edge: most 2026 home batteries promise 60–80% of original capacity at the 10-year mark, and real LFP cells often do better. This chart is deliberately conservative and uses the warranty floor, resetting at each replacement.

Usable capacity, warranty-floor basis

Cumulative view

Running total — money in vs. money back

Cumulative net position each year: total spend so far (system, STCs/rebates, cleaning, replacements) subtracted from cumulative bill savings.

Rooftop solar only Rooftop solar + battery SolarCloud

How this is calculated — assumptions & sources

Average bill: $500/quarter used as the default, in line with Canstar's national average electricity bill research. canstar.com.au
Daily supply charge: defaults to $1.10/day (≈$400/yr), within the ~90c–$1.20/day national range reported by Canstar/AER. At Max/100% coverage, SolarCloud's own figures reconcile to a fully zeroed ongoing bill — their "savings" is just total 25yr bill cost minus system cost — meaning SolarCloud is effectively paying your supply charge for you out of the credit. Rooftop options (Option A included) can't do this: export credit only ever offsets metered usage, so the full supply charge lands on top regardless of system size. We now include it in Option A's total cost, and exclude it from SolarCloud's, since it's already covered there.
System pricing: Budget/Standard/Premium $/kW rates are set to match the installed price ranges shown further down SolarCloud's own comparison page (sourced from SolarQuotes) and their disclosed $7,800 reference system.
STC incentive: defaulted to $295/kW, calibrated directly off SolarCloud's own published reference figures ($1,950 STC value disclosed against their comparison system). Actual STC value depends on your zone rating, installation date and the live STC spot price.
Cleaning: we've used an independent market estimate of $175/visit, twice yearly ($8,750 over 25 years), rather than SolarCloud's own on-page figure of $1,275/25yrs, which implies roughly $25/visit — well below typical quoted panel-cleaning callout rates. Edit this if your own quotes differ.
Monitoring: not charged as a mandatory cost in this tool. Most modern inverters include free app-based monitoring; SolarCloud's own page quotes $7,200/25yrs for this on the standard-solar side, which we think overstates a typical household's real cost, so we've left it out rather than bias the comparison.
Inverter replacement: two replacements over 25 years, calibrated to SolarCloud's disclosed $5,304 figure (≈$2,650/unit for a 6.6kW system, scaled by system size), with no government incentive applied — matching how inverter replacements are actually treated.
Battery prices (2026): $700–$1,150/usable kWh installed depending on brand, drawn from installer price trackers (WhySolar, Gridly, Aussie Solar Tech, SolaX) current to early–mid 2026.
Cheaper Home Batteries Program: ~$250/kWh on the first 14kWh, 60% of that rate for the next 14kWh (to 28kWh), 15% beyond — applied only to the first battery. Two replacement batteries over 25 years are costed at full price with no rebate, as government battery incentives don't apply to like-for-like replacements.
Battery degradation: warranty-floor capacity retention at year 10 varies by brand — BYD ~60%, Sungrow/Tesla Powerwall ~70%, Sonnen ~80% — industry standard is generally 60–80%. Modelled as straight-line decline from 100% to the warranty floor, resetting at each of the two replacements.
SolarCloud — cost and savings: anchored directly to SolarCloud's own live quote tool (checked 30 July 2026), not a generic $/kW estimate. At their "Max, 100% coverage" tier on a $500/quarter bill, their tool sizes a 15.3kW / 153-panel system costing $22,797, with an estimated $27,500 credited over 25 years. All coverage tiers and bill sizes in this comparison scale linearly from that real reference point. Note that "100% coverage" is their top purchase tier, not a promise of a $0 bill — on their own numbers it credits ≈55% of total bill cost over the term, which lines up with the "average reduction of up to 55%" figure SolarCloud cites in its own press material.
SolarCloud — how the credit is funded: per SolarCloud's published indicative-return methodology, panel output is sold at a base wholesale-style price (11.2c/kWh in their worked example) escalating ~2%/year, after a management/O&M cost of roughly 20% of gross revenue. That's why the credit lands well below what you'd get if 100% of the same generation were valued at full retail rates — the gap is the cost of not owning or maintaining physical hardware. We've modelled the 25-year total as a 2%/year-growing series to reflect that escalation, rather than a flat annual figure.
SolarCloud — cleaning, monitoring, replacement: bundled into their price as the hosting operator's responsibility, per their published comparison table — $0 to the customer.
Panel degradation: ~2% in year one, then ~0.5%/year — standard manufacturer performance-warranty shape — applied to both rooftop columns. SolarCloud generation is modelled without customer-side degradation exposure, since panel upkeep and replacement sit with the operator.