Duke Energy executives appeared before the Public Service Commission Thursday to answer questions about overcharging customers.

The utility giant admitted it overcharged customers in August.

The charges stemmed from a one-time billing cycle adjustment that added 12 days of service to customers' monthly bills - adding as much as an extra $100 to bills.

The company has about 267,000 customers in Pinellas County.

Duke has credited customers whose bills leaped higher. But today before the Public Service Commission, Duke Executives said what happened is completely legal, and there are no new rules in place to prevent it from happening again.

“There are certainly not, because everything that we've done with this re-route has been according to Public Service Commission rule and procedure, so we've been following the rules that are laid out for us to follow,” said Sterling Ivey, Duke Energy.

Still, in this case, even Public Service Commissioners are praising Duke for not following through on following the rules.

“The company did certainly, it appears, jump right on it,” said Lisa Polak Edgar, Public Service Commissioner.

Energy use here in Florida typically peaks in July and August, making the overcharges look especially high. But, critics argue it doesn't matter what time of year it is - the billing practice ought to be banned.

The Public Service Commission is looking at limiting the number of extra days power companies can tack on to monthly bills when billing cycles go through adjustments.

But, Republican State Sen. Charlie Dean says lawmakers may have to step in to protect pocketbooks up and down the state.

“I, for one, think that billing first and then trying to credit later is just an inappropriate action,” he said.