The one state incentive table we can quote from the regulator

The Self-Generation Incentive Program is administered under the California Public Utilities Commission. Its rate table sorts households into budget categories, and the difference between the top and bottom rows is a factor of more than seven. This is that table as the regulator prints it, before we set it out in columns:

Multiply those against a real pack and the spread becomes concrete. On the 10 kilowatt-hour unit used elsewhere on this site, the equity storage rate of $1,100 ^[1] is worth $11,000 — more than most of the installation. The general small residential rate of $150 ^[2] is worth $1,500 on the same pack.

Two further budgets sit in between: a resiliency rate of $1,000 ^[3] for customers meeting its own criteria, and a regional residential rate of $1,100 ^[4] tied to a specific geography and utility pair.

Notice the unit in the rate column. These are dollars per kilowatt-hour of installed storage, so the rebate grows with the size of the pack — and that quietly argues for buying a larger one than the rest of this site would recommend. It is worth being precise about when that argument holds and when it does not.

Capacity beyond what your household consumes during the expensive window earns nothing on a bill. It discharges into hours that were already cheap. A per-kilowatt-hour rebate does not change that: it reduces the price of the extra capacity without giving the extra capacity anything to do. On the general small residential rate of $150, an unused kilowatt-hour is bought at full price less $150 and still returns zero, which is a discount on a purchase rather than a reason to make it.

At the equity rate the arithmetic genuinely does change, because $1,100 a kilowatt-hour is a substantial fraction of what a kilowatt-hour of storage costs to install. Where a rebate covers most of the marginal capacity, capacity that earns nothing on the bill can still be worth having for the outage it covers — but that is a resilience decision made with a subsidy, not a savings decision, and the two should be written down separately.

The rule we apply on the worksheet: enter the rebate, then check whether the pack is still above the ceiling the sizing tool prints. A rebate that makes an oversized pack affordable has not made it useful.

Three of the four rows carry a closing note in the regulator’s own table. We reproduced that wording exactly rather than paraphrasing it, because “available through” a year that has already passed is precisely the kind of detail a marketing page drops while keeping the attractive number.

Incentive programmes also run out of money independently of their dates. Budgets are allocated by tranche and close when subscribed, so a rate that is nominally open can be practically unavailable. The only reliable check is the programme’s own current budget status at the moment you apply — which is a phone call, not a web page.

Our own position on this: the calculator takes a rebate figure from you rather than selecting one for you. If you have a written confirmation of a rate, enter it. If you have a table entry and a hope, enter zero and treat any rebate that arrives as an improvement on the answer rather than a load-bearing part of it.