Two values for the same kilowatt hour
Standard residential tariffs apply a retail-rate offset for in-period consumption, with year-end surplus reconciled at avoided cost. So the destination of a kilowatt hour, not just the quantity, determines what it is worth to you.
That makes oversizing a poor use of capital. A system deliberately built beyond your consumption produces electricity that will ultimately be settled at avoided cost, and you paid retail-level installation costs to generate it.
Ask your installer what percentage of your annual usage the proposed system covers, and ask for the design to be built from your last twelve months of electricity bills rather than a generic household profile.
Ask specifically how the year-end reconciliation was treated in the savings projection. A model that carries surplus forward at the retail rate indefinitely is describing an arrangement the tariff does not offer.
What you can change for nothing
Because in-period offset is worth more than year-end surplus, the share of production your household actually absorbs matters. Raising it is the cheapest improvement available and it needs no equipment.
Running laundry and dishwashing during daylight, and scheduling any vehicle charging for the middle of the day rather than the evening, shifts consumption into the production window. Unlike panel choices you can adjust it at any time.
If your consumption is about to change, say so before the design is finalised. An electric vehicle, a heat pump replacing gas heating or an additional occupant all move the number, and designing for a load you know is coming is easier than expanding later.
Ask for models at two or three sizes with the in-period offset shown for each. Seeing where the return stops improving with size is the clearest way to make this decision rather than accepting a single proposal.
The timeline the law gives you
Missouri's Net Metering and Easy Connection Act covers qualified net metering units of 100 kW or less and applies to regulated utilities, municipal electric utilities and rural electric cooperatives alike.
For systems of ten kilowatts or less the application uses an all-in-one document combining a simple interconnection request, simple procedures and a brief set of terms and conditions, and the utility must review and respond within 30 days of receipt. For larger systems up to 100 kilowatts the window is 90 days.
Ask your installer the date the complete application was submitted so you know when a response is due, and ask for the expected date of permission to operate rather than the installation date. Only the second earns you anything.
And build the arithmetic without the incentives people assume: the federal residential credit ended for property placed in service after December 31, 2025, utility rebates have largely been discontinued, and the property tax exemption was held unconstitutional in 2022.
Building the number from confirmed pieces only
Three things people expect in Missouri are either gone or unreliable, and a quote built on any of them overstates your return. 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 now receives no federal credit.
Utility solar rebates historically existed here but have largely been discontinued. If a rebate appears in a quote, confirm directly with your own utility whether it is currently open, what it pays and whether funding remains, before you sign anything.
And the property tax exemption most guides still list was held unconstitutional by the Missouri Supreme Court on August 9, 2022. Ask your county assessor how residential solar is being assessed at your address rather than assuming an exemption applies.
What does exist is net metering under the Easy Connection Act and the electricity you stop buying. Ask any installer to rebuild the arithmetic from those two things alone, and treat resistance to producing that version as informative in itself.