Power could be out for weeks in Louisiana. Avoiding long outages will be incredibly expensive

The power is off for nearly a million customers in Louisiana after a Category 4 storm slammed into the region. But that's not the biggest problem facing the storm-ravaged state: It's the possibility of perhaps hundreds of thousands of people going weeks, if not longer, before power is restored.

Although New Orleans Mayor LaToya Cantrell said Tuesday evening that some parts of the city could start to get power back Wednesday, it's not at all clear when the power will reach most of the affected homes and businesses. And it could be worse outside the city. Officials at St. Charles Parish, which is west of New Orleans, are warning its more than 50,000 residents to "prepare to be without power for at least a month." Entergy, the major electric utility in the region, said Wednesday it has restored power to parts of Eastern New Orleans, with power provided by its New Orleans Power Station. But it said it will still be difficult to restore power to the broad swath of customers.