Fuel Costs Continue To Fall in Iowa. As of Wednesday, the price of regular unleaded gasoline averaged $2.70 across Iowa according to AAA. Prices fell 5 cents from last week’s price and are down 18 cents from a year ago. The national average on Wednesday was $3.03, down 4 cents from last week’s price. Retail diesel prices in Iowa fell 2 cents this week with a statewide average of $3.28. One year ago, diesel prices averaged $4.00 in Iowa. The current Iowa diesel price is 26 cents lower than the national average of $3.54. Wholesale ethanol held steady and is currently priced at $2.16. Propane prices averaged $1.55 per gallon in Iowa. Home heating oil prices had a statewide average of $2.90 per gallon. Tips for saving energy on the road or at home are available at energy.gov and fueleconomy.gov.