The finished model, and the rules behind its numbers:
- The verdictpayback year and net earnings after payback, from the same series the cashflow chart plots — the two can never disagree.
- One accounting rulewholesale market revenue is folded into the headline payback and totals; bill-impact figures stay honest (self-consumption + demand only).
- The leversdiscount rate, analysis years, price escalation (years 1–3 and 4+), export escalation and depreciation — every number on the page follows them.
- Three tabsOverview tells the story, Energy explores production vs consumption, Costs is installer-only and never reaches the customer.
- Customer shareShare with Customer publishes a read-only link with installer cost detail stripped out — safe to send as-is.
- Stalenesschange an upstream input and the page flags the model stale and recalculates, so an exported proposal never trails the inputs.
How the underlying production and dispatch numbers are made lives in the modelling guide.
The Output page is the finished financial model — the page a proposal is built from. The verdict hero answers the customer’s only question (when does it pay for itself, and what does it earn after that), the charts below show how, and the bottom bar turns it into a deliverable. This page explains the accounting rules those numbers follow.
The verdict
The headline states the payback year and the net earnings after it, over the analysis horizon. The “then earns” figure is taken from the same series the cashflow chart plots — cumulative cashflow, net of the upfront investment — so the hero and the chart can never disagree. Underneath sit the four finance figures: IRR, NPV (at the discount rate you set), ROI and LCOE.
One accounting rule
When the battery earns wholesale market revenue (spot arbitrage), that income is folded into the headline — payback, annual benefit and totals — with no separate callout. The bill figures stay honest: “bill saved per year” counts only self-consumption and demand reduction, because market revenue never appears on an electricity bill. If the headline benefit reads higher than the bill saving, that gap is the market revenue.
The levers
Adjust assumptions (on the Cashflow card) opens the levers every number on the page follows:
- Discount rate — what future dollars are worth today; drives NPV and LCOE.
- Analysis years — the horizon the model runs over.
- Price escalation — how fast electricity prices rise, split into years 1–3 and 4+ so near-term contract rates and long-run drift can differ.
- Export escalation — feed-in tariff drift, separate from usage prices (default flat).
- Depreciation — asset write-down for commercial customers.
Applying recalculates the whole model. If you change an upstream input elsewhere in the project, the page flags the model stale and recalculates too — an exported proposal never trails the inputs.
The three tabs
- Overview — the story: verdict, cashflow, energy flow, environmental impact.
- Energy — the chart explorer: solar vs load, monthly balance, interval heatmap, energy flow.
- Costs — installer-only: the priced equipment, bill impact and revenue breakdown. Hidden from anyone on a customer share.
What the customer sees
Share with Customer publishes a read-only link to this page with the installer-only cost detail stripped out server-side — the Costs tab and its data simply don’t exist in what they receive, so the link is safe to send as-is. The PDF proposal and the data bundle come from the same model via the bottom-bar menu.