Put two or three batteries in front of a customer and read the numbers for each:
- What can differthe catalogue model, the installed $/kWh, the dispatch strategy, and optionally a pinned size.
- What stays sharedroof, solar, tariff, incentives, replacement costs and financial assumptions — identical in every row.
- Real runs, not estimateseach option is its own sizing sweep, so its size, savings and payback are modelled independently.
- Modelled on demandnothing runs until you press Model options; editing Base re-models every option, editing one option re-models only that one.
- Reuse a setsave a price ladder or brand shortlist to the Library once, then load it onto later projects.
Peak demand reduction only pays on a site whose bill actually carries a demand charge. On a site without one it can make an option look worse than Base, because the battery spends charge shaving peaks that cost nothing instead of offsetting usage.
Most battery conversations end the same way: the customer wants to know what happens if they spend less, or buy a different brand. Battery options let you answer that with modelled numbers instead of a guess. An Analysis project can carry up to three options beside its Base battery, and each one is sized and valued in its own right.
What an option is allowed to change
An option is a second battery setup that differs from Base in at most three things: the catalogue model, the installed cost per kWh, and the dispatch strategy. You can also pin it to a fixed size if you want to hold capacity still and vary only the price. Everything else is deliberately fixed.
- Shared by every row: the roof, the solar array, the tariff, the incentives, the replacement costs and the financial assumptions.
- Free to differ: battery model, $/kWh, dispatch strategy, and an optional pinned size.
That constraint is the whole point. Because nothing else moves, a difference in NPV between two rows can only have come from the battery, which is what makes the comparison worth putting in front of a customer.
Each option is a real sizing run
An option is not Base's result with a different price multiplied through it. Each one is a full sizing sweep of its own, so it finds its own best size, its own savings and its own payback. A cheaper battery is usually worth sizing larger, and the matrix will say so rather than assuming it. If you pin a size, the sweep tests just that size instead.
Options are modelled on demand, never automatically, because each one costs a sweep. Set them up on the Solar & Battery step, then press Model options on Recommendation when you want the numbers. Editing Base re-models every option; editing one option re-models only that one; renaming an option re-models nothing.
Reading the comparison
The Battery Options card on Recommendation puts Base and every option on the same scenario, one row each, with the battery, the price per kWh, the net cost, year-one savings, payback and NPV. The best NPV among freshly modelled rows is marked. Clicking a row puts that battery on the rest of the page, so the scenario cards, the sizing matrix, the trade-off table and the energy schedule all swap together and you are never reading one battery's matrix beside another's cards.
Reusing a comparison set
A price ladder or a brand shortlist is usually the same from job to job. Save the options on a project as a set in the Library, then load that set onto the next project and the rows arrive already filled in. Sets belong to your company; sets published globally are available to load but cannot be edited.
For how the underlying sizing and ranking work, see How Are the Recommendations Picked?