The 90-minute outage was blamed on equipment breakdown. Stranded riders used emergency stairs.
A power failure on Tuesday left amusement park guests temporarily stranded on rides at Valleyfair.
The electricity was out at the popular Shakopee amusement park from about 4:30 p.m. to 6 p.m., according to Xcel Energy spokeswoman Mary Sandok. The cause was determined to be equipment failure, she said.
During the outage, people were stranded on the Ferris wheel and the Wild Thing roller coaster.
The outage prompted Valleyfair officials to close the park for the remainder of the day.
No one was injured, said Valleyfair spokesman Todd Larkin. The park used a backup generator to power the Ferris wheel to evacuate riders, Larkin said.
Those on the roller coaster were helped to walk down the side, he said. The park should be open its regular business hours on Wednesday.
Sydney Ellerbe, 18, said she and 10 of her friends had driven from Wisconsin to spend the day at the park. The group was heading to get on a ride when somebody told them the power had gone out.
"It was annoying," Ellerbe said.
She said the group waited about an hour and a half to get a refund for their tickets and received a total of $150 for their inconvenience, after they had paid about $30 per ticket.
"There's no way we're ever going back," Ellerbe said.
Cal Delaney said he was the next in line to get on the Wild Thing when the power went out. "It was weird. No one knew what was going on," he tweeted.