The company is asking the State Utilities Commission to raise homeowners' bills by almost 10 percent.
Several people and groups in attendance at a public hearing represented the environment and people on fixed incomes.
"The Progress Energy rate hike just takes too much of that away from seniors who need it to pay for gasoline, food, medicine and other needs," said AARP's Steve Hahn.
They argued that case before the commission, and called Progress Energy greedy and its proposal an assault on working families.
Progress wants to collect $183 million extra a year to pay for upgrades to the Shearon Harris power plant and three new natural gas plants.
A preliminary settlement would allow the hike to come in two waves -- a 4.7 percent jump the first year, and a one percent increase the second, which is less than the 11 percent Progress Energy originally proposed.