JOLIET, Ill. (Michigan News Source) – Michigan drivers already dealing with elevated fuel prices could have another reason to keep an eye on the numbers at the pump after a major Midwest refinery that supplies the state suddenly went offline.

Power Outage Shuts Down Joliet Refinery

ExxonMobil’s Joliet refinery in Illinois was knocked offline Sunday, September 13 after a power outage hit the facility around 3:30 p.m. Power was restored around 7 p.m., but the outage triggered the refinery’s safety flare system and a plant-wide shutdown. ExxonMobil is investigating the cause.

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The refinery can process about 275,000 barrels of crude oil per day and produces roughly 11 million gallons of gasoline and diesel daily, according to ExxonMobil. The Joliet facility accounts for about 6% of the Midwest’s total refining capacity, with its fuels transported by pipeline to Michigan, Illinois, Indiana, Iowa, Ohio, Pennsylvania and Wisconsin.

Michigan Prices Could Feel the Squeeze

Taking that much fuel production offline can put upward pressure on prices throughout the Great Lakes region, particularly as BP’s massive Whiting, Indiana refinery undergoes maintenance and already-tight global fuel supplies leave less room to absorb another disruption. The war in Iran and Ukrainian attacks on Russian refineries are also putting additional strain on global fuel supplies.

Michigan is among the states experiencing some of the largest recent gasoline-price increases in the country. Today’s AAA national average is $4.36 a gallon, while Michigan drivers are paying even more at $4.54 a gallon

How much the Joliet shutdown ultimately costs Michigan motorists will depend largely on how long it lasts. Industry estimates indicate the refinery could return to normal operations by the end of the week. A quick restart could limit the damage, while a prolonged outage could further tighten supplies and push gasoline and diesel prices higher across Michigan and much of the Midwest.

Michigan has seen this movie before: a lengthy three-and-a-half week Joliet refinery outage in 2024 contributed to regional supply concerns and prompted state officials to seek federal action aimed at preventing shortages and price spikes.