Is solar worth it in Iowa in 2026?

How Iowa pays for your solar power

Net metering at the retail rate. MidAmerican and Alliant credit solar exports at the full retail volumetric rate for 20 years, measured every 15 minutes; a value-of-solar rate can replace it for later systems after July 1, 2027.

In the calculator, 40% of your solar output is used at home at the retail price and the rest is exported at about 100% of retail, so each solar kWh is worth 100% of the retail price on average. Change it if your utility pays more or less. Method

State or utility incentive	What it is worth
Sales tax exemption on solar energy equipment	State sales tax exempt (Iowa Code 423.3(90))
Property tax value exclusion	Solar installation cannot raise assessed value for 5 full assessment years

How exports are credited

Iowa’s rule is set by statute, Iowa Code 476.49 (Senate File 583, 2020). It covers the state’s two rate-regulated electric utilities that serve most homes, MidAmerican Energy and Interstate Power and Light (Alliant Energy), according to the Iowa Utilities Commission. A utility files either a net billing or an inflow-outflow tariff. Both utilities’ current programs for new systems are inflow-outflow.

Inflow-outflow works in short intervals. MidAmerican and Alliant both measure every 15 minutes. You pay the retail volumetric rate, riders included, for power delivered to you in each interval. Energy you send to the grid in each interval is credited in dollars at the outflow purchase rate. The statute sets that rate at the applicable retail volumetric rate until the commission approves a value-of-solar method, and it stays at that rate for 20 years for a facility, even if ownership changes.

The credit offsets volumetric charges only, so fixed charges are not credited. Credits carry forward but are forfeited at the end of an annual period, which you choose as January or April at interconnection. Alliant states the credits cannot be turned into cash.

To qualify at the full rate, the system must be behind your meter, no larger than 1 MW AC, and able to produce no more than 110% of your annual usage. Alliant prorates the credit for the oversized portion and pays that share at its avoided cost rate.

The value-of-solar process starts when a utility petitions after July 1, 2027, or when statewide distributed generation reaches 5% of peak demand, whichever is earlier. The commission reported 3.90% as of 2025. Once a rate is approved, it can change by no more than 5% a year, and a facility installed under the earlier rate keeps its own terms for its 20-year period. Co-op and municipal customers follow their own utility’s rules.

State incentives in 2026

• Sales tax exemption. Iowa Code 423.3(90) exempts the sale of equipment primarily used to collect and convert sunlight into energy, or to move that energy to storage or a point of use.
• Property tax. Under Iowa Code 441.21(8), installing a solar energy system on residential property does not increase actual, assessed or taxable value for five full assessment years.

The Iowa solar energy system tax credit (Iowa Code 422.11L) is not open to new residential systems. The Department of Revenue reports it is available for residential property placed in service from 2012 through 2021. The federal residential credit also ended for systems installed after December 31, 2025. See why the federal credit ended.

What it means for payback

Because exports earn the retail volumetric rate for 20 years, oversizing up to the 110% limit costs little in credit value. Sizing to your annual use, with a modest margin for an EV or heat pump, is a reasonable target. The main risk is seasonal: credits carry forward only until the January or April reset, and anything left is forfeited. A system that overproduces in summer should still be sized so you can use the banked credit before the reset.

The retail-rate credit and 20-year term attach to the interconnection date, so the timing of a signed application matters before the value-of-solar change. Batteries add less value here than in states that credit exports below retail. Alliant requires all battery charging to come from on-site generation, and standalone storage does not qualify. See are solar batteries worth it and how we calculate payback.

Other rules worth knowing

• Usage basis. Alliant uses the most recent three-year average usage before installation to test the 110% limit. With under three years but over one, it uses the latest 12 months.
• Expansions. Adding to an existing system needs a new interconnection application. Alliant places any increase in AC nameplate capacity on the inflow-outflow schedule.
• Rates and fees. The statute bars charging inflow-outflow customers any fee not charged to others in the same rate class, and bars treating them as a separate rate class before the value-of-solar decision or July 1, 2027.
• Application size. MidAmerican uses a simpler Level 1 application for systems of 20 kVA or less.
• Solar access. Iowa Code chapter 564A lets a city council or county board of supervisors designate a board to grant a recorded solar access easement, which protects access to sunlight against later development on the neighboring parcel.
• Older systems. Alliant customers whose applications were completed before December 30, 2020 stay on the earlier net metering pilot unless they choose to switch. Compare with net metering vs net billing.

Berkeley Lab does not publish a Iowa median from enough systems, so the calculator starts from the U.S. median of $3.60/W. Put your own quote in.