Exxon Mobil took its 264,000-barrel-per-day refinery in Joliet, Illinois, offline after a power outage triggered the plant's safety flare and a shutdown. The outage began at about 3:30 p.m. CT on Sunday, with power restored around 7 p.m., and the cause remains under investigation. IIR Energy said units were being stabilized and expected the refinery to return to normal service by the end of the week. The facility supplies key fuels to the U.S. Midwest and can produce about 11 million gallons of gasoline and diesel daily. The disruption comes as the Iran war, Ukrainian attacks on Russian refineries and strong exports pressure fuel supplies, with the U.S. national average diesel price surpassing $6 a gallon for the first time last week.