A series of refinery outages in Chicago and Ohio have generally increased Midwest prices for petroleum products relative to the US average, particularly gasoline, according to the US Energy Information Administration (EIA). The outages reflect an unusual decline in refining activity near the end of the high-demand summer season and have drawn down regional inventories.

On 15 July, ExxonMobil’s Joliet refinery outside of Chicago, with 251,800 barrels per day (b/d) of capacity, was shut down on an emergency basis in response to a power outage brought on by severe weather conditions. The shutdown took the refinery offline for several weeks before it could safely resume operations. Operators reported they had begun bringing the facility back online as of 8 August, and later reports have since indicated that the Joliet facility has resumed normal operations.

In Ohio, operators also reported temporary unit shutdowns at Cenovus’ 183,000-b/d Lima and 150,800-b/d Toledo refineries. Since the week ending 12 July, just before the Joliet outage, to 9 August, Midwest refinery utilization decreased 11 percentage points to 86% because of the outages, reducing refinery production of gasoline, diesel, and other refined petroleum products.

As these refineries re-entered service, Midwest refinery utilization increased more than 10 percentage points the following week, to 97% as of 16 August.

Lower refinery utilization means refineries produced less gasoline, which has resulted in noteworthy draws on Midwest gasoline inventories, EIA said. In the week ending 19 July, immediately after the Joliet outage began, Midwest gasoline inventories drew down by 2 million barrels, falling below 2023 levels and the five-year (2019–2023) low.

Through 9 August, weekly inventory data show that Midwest gasoline inventories remained at about 46 million barrels, between 4% and 7% below the five-year average, depending on the week. The return of these refineries to service contributed to regional gasoline inventories increasing 1.3 million barrels the week of 16 August. Nonetheless, below-average inventories have put pressure on Midwest gasoline prices.

Retail gasoline prices in the Midwest are typically lower than the US average because of production from local refineries and lower regional fuel taxes. However, the average retail gasoline price in the Midwest has been within 1% of the US average for three consecutive weeks following the outages, according to EIA’s Gasoline and Diesel Fuel Update.