Des Moines Register: Some powerful industries have begun battling over Gov. Kim Reynolds’ proposal to set a renewable fuel standard in Iowa, a move that would require retailers to offer motor fuel with higher levels of ethanol and biodiesel. A group that includes convenience stores and trucking businesses is slamming the governor’s bill, saying the legislation would reduce consumer choice, raise prices for Iowa motorists and cost retailers at least $1 billion to upgrade pumps and tanks. On the other side are the Iowa Renewable Fuels Association and ag groups. They are releasing a study that says the mandate would create 3,500 jobs in Iowa and add nearly $550 million in household income from 2022 to 2026.