Hi Alyson,
In SAM 2018.11.11, the battery replacement cost is an input on the Battery Storage page. You can only enter a single value for the replacement cost, but you can make it less than the battery installation cost on the System Costs page to model the assumption that battery costs will decline over time. You can also use a negative battery cost escalation rate to model a scenario where battery costs decline on an annual basis. You can see the battery replacement cost on the Cash Flow tab of the Results page. Note that SAM applies the inflation rate from the Financial Parameters page to the battery cost, so the battery replacement cost is affected by both the battery replacement cost escalation rate from the Battery Storage page and the inflation rate from the Financial Parameters page.
In the next version of SAM, it will be possible to assign a specific battery replacement cost on a year-by-year basis.
The ITC (Investment Tax Credit on the Incentives page) is a tax credit that applies in Year 1 of the project cash flow. You might use one of the direct cash incentives rather than the tax credit to represent a cash saving to the project (in this case from a reduction in battery replacement cost). The IBI and CBI are cash payments that occur only in Year 1. The PBI is an annual cash payment per unit of electricity generated, so you could use it to account for the battery replacement cost, but I think the method I describe in my first paragraph above would be a better approach.
Best regards,
Paul.
