About 70,000 customers remain without power; 59,000 are in the northern suburbs.
The utility said crews have been working around the clock to restore electricity to 850,000 customers since the storm hit.
Doctors and nurses at Vista Medical Center East were working with real power Thursday. The Waukegan hospital functioned at full capacity for two and half days using generators, which meant no air conditioning. Dozens of portable units were brought in to keep patients cool. The hospital was back on line Wedneday afternoon.
"On Tuesday, I did reach out to my elected official to get them to prioritize hosptials," said Barb Martin, CEO of Vista Health System.
Martin is livid that her hospital had to wait a day and half longer than Great America.
"Hospitals have to be the number one priority when power goes out. We are a 24/7 operation, that place where disaster victims go to," said Martin.
"If the amusement park was on the main line and we are focused on the main line, they may benefit by the fact where they are connected. If the hospital is further downstream before the main line is connected, that might cause it to be down there as well," said Fidel Marquez, ComEd.
Despite the delay for the hospital, ComEd said Thursday afternoon it was ahead of pace restoring power. Eight hundred and fifty crews, half from out of state, are working around the clock trying to get everyone back on line by Friday.
Clifford Westerby has been coping with an oil lamp that was used as a decoration in his house.
"Going to bed a lot earlier, as soon as it gets dark," said Westerby.
Dr. Ellis Neiburger has been in the dark since Monday as well. The Waukegan dentist has been forced to cancel over 70 appointments.
"We've probably lost thousands of dollars in business, but unlike the restaurant across the street, we're not throwing out large quantities of food stuffs," he said.
Lake County, Illinois, is the hardest hit by the storm and power outages, with so many trees down and communities in the dark, the county has declared a state of emergency.
"It's really terrible. Obviously, the drivers are feeling impatient. When someone doesn't have electricity that means they can't take a shower, can't sleep, don't have air conditioning. So many people have braved it out and stayed at home, and others have filled up hotels throughout Lake County," said David Stolman, Lake Co. chairman.
Officials in Lake County hope they can speed up the process to get more state funding and assistance. For now, people are just hoping they can have the power back on and put away the generators.