After a noon fire destroyed one of its transformers, Salt River Project was working to bring back power to some 80,000 customers in Mesa and parts of Apache Junction.
The fire at Thunderstone substation not only destroyed a transformer, but overloaded SRP's system within Mesa resulting in outages in homes and businesses.
SRP spokesperson Patty Likens said Our system became pretty overwhelmed in that area.
SRP was working to deliver bags of ice, and Mesa officials are asking homeowners and businesses to conserve energy.
Meanwhile, SRP is hoping to restore power by Thursday night, according to Likens.