Reliant Energy / December Bills

I would like to know how Reliant Energy is justifying the December 2005 power bill increases?

Out of the 6 people in my office 5 of them have Reliant power. Each person’s bill has at least doubled for the month of December. Some have tripled. Does anyone know if they have an explanation for this other than a price increase which doesn’t come close to the doubling bills. The one person who doesn’t have Reliant Energy said their bill went down for December.