Law moving forward in Iowa that would ban solar on any land in state measured at minimal “corn suitability rating.”
An Iowa politician submitted legislation that could dictate to landowners that they are forbidden from leasing their land for commercial solar power, if their soil meets a minimum ‘corn suitability rating’. The legislation, submitted by Senator Dan Zumbach, has already moved past Iowa’s first round of political vetting and is being discussed in the broader state law making body.
The specific text of the legislation – SF 2321 – states:
The bill provides that the owner or manager of agricultural land shall not install a commercially owned solar panel field unless the solar panel field has a CSR of 65 or lower, the solar panel field is at least one-half mile from the next solar panel field, and the solar panel field is located at least 1,250 feet from the nearest neighboring landowner.
According to the farm management firm Hertz, the Corn Suitability Rating measures the potential soil productivity based on soil profile, slope, and weather conditions. The most recent version is labeled CSR2, and the values it assigns are used by appraisers, real estate agents, and farmland investors in order to evaluate land values and analyze comparable (agricultural/corn land) sales.
An Iowa academic uploaded a walkthrough for determining the CSR2 of any specific plot of land via an online mapping tool. This author picked a random plot of land in the middle of the state, and got an output of the below map:
Per this rating, if the legislation were passed, this 283 acre parcel wouldn’t be viable for solar power. While there is seemingly 53 acres of land rated below a CSR of 65, 18% of the land highlighted above, the spread out nature of it – the yellow sections – does now allow for the needed continuity and shape that solar requires.
According to the website IowaCorn.org, 57% of the state’s corn goes directly to ethanol – which makes up approximately 7.4 million acres of land. This volume represents 27% of all ethanol manufactured in the nation.
Roughly speaking, 7.4 million acres of ethanol fields (less than 10% of US corn) could be used to generate 64% of the electricity used in the United States in 2021. This relatively small amount of land is sufficient to power more than 100% of the 3.2 trillion miles of passenger vehicles driven annually, were we to convert to a fully electric fleet.
