Iowa pays about 14.0¢ per kilowatt-hour for residential electricity and receives about 4.5 kWh per square metre per day of sunlight — 34th and 28th respectively among the 50 states and DC tracked here. Those two numbers set the ceiling on what rooftop solar returns in Iowa, and they point in the same direction.
Where Iowa sits against the rest of the country
Iowa is 0.8¢/kWh below the median residential rate across this dataset (14.8¢/kWh) and 0.1 kWh/m²/day below the median insolation (4.6 kWh/m²/day). Under this site's standard assumptions, that combination puts Iowa 37th of 51 for modeled payback speed, at 14.9 years against a dataset median of 13.5 years.
What actually drives payback in Iowa
Iowa ranks in the lower half on both inputs — 34th for electricity price and 28th for sunlight. Swap Iowa's sunlight for the dataset median and payback moves to 14.7 years (0.3 years of swing). Swap its electricity rate instead and payback moves to 14.3 years (0.7 years of swing). The rate swap is the larger of the two, so what a kilowatt-hour costs is the input deciding the outcome in Iowa.
State incentives on record
Recorded for Iowa: State solar tax credit historically tied to federal credit and now in wind-down; net billing under 2020 SF 583; property tax exemption.
No federal credit is applied above (Section 25D expired 31 December 2025), and export terms often matter more than the headline rate (net metering guide).
The modeled system, in numbers
At Iowa's sunlight level a 7 kW array produces roughly 8,968 kWh a year, worth about $1,256 in first-year bill savings at 14.0¢/kWh against an assumed $22,400 installed cost. A ten-year payback at this sunlight level would require a residential rate of about 22.4¢/kWh, which is 8.4¢ above what Iowa households pay today.
States with comparable economics
Iowa's closest analogues by modeled payback are Utah (15.0 years), Wyoming (15.1 years), Arkansas (15.2 years). They arrive there from different rate and sunlight combinations, so their incentive rows are the useful comparison.