A statutory ceiling, not a design target
Sections 70-2001 to 70-2004 require net metering to be offered at up to 25 kW. A typical residential system is a fraction of that, so the ceiling is not what constrains you.
Above 25 kW the statute does not require net metering, though utilities may allow it at their discretion. For a residential project that is unlikely to arise.
So treat the statutory figure as a guarantee rather than a guide. It tells you the arrangement will be available; it says nothing about what size is right for your household.
Build from your last twelve months of bills and ask what percentage of your annual usage the proposed system covers.
The question that actually decides size
Ask your district whether credits carry forward, whether there is an annual reconciliation, when it falls and what happens to any remaining credit.
If unused credit is forfeited at a reconciliation, as it is in Kansas on March 31, Washington on April 30, Oregon at the end of the March billing cycle and Montana at the annual settle-up, then a system generating an annual surplus donates it.
If there is no such reconciliation, as under the PNM arrangement in New Mexico where credits do not expire while the account is open, a modest surplus costs much less.
That single answer changes the right system size more than anything else about your roof, and it is not in the statute.
When building larger is justified
A concrete planned increase in load with a timeline: an electric vehicle, a heat pump, an addition, a shop.
An electric vehicle is the most quantifiable, since you can estimate the annual kilowatt hours it will add from your expected mileage reasonably well.
A heat pump raises winter consumption, which is when the array produces least. That is worth modelling rather than assuming, particularly if your district reconciles credits annually.
A general expectation of using more electricity later is not a reason. It is the most common justification offered for an oversized system and the least defensible.
Costing it out under public power
The 30 percent federal Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, so a cash or loan purchase in Fremont receives no federal tax credit, and Nebraska has no state solar tax credit.
Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements, so ask what a provider claims and what reaches you in the rate.
What exists is net metering to at least 25 kW under the statutory floor, on crediting terms set by your own district.
Ask your district about annual reconciliation, then ask for the design built from twelve months of your own bills with a smaller system modelled alongside.