Baltimore Gas and Electric BGE Back Billing Baltimore Maryland

Baltimore Gas and Electric sent us a bill, after we received our Smart Meters, for over $1000. Stating they were estimating our past usage going back to May, 2013. So they back charged onto our current bill all of the previous 'estimated' usage, despite the fact that A: we've already paid our previous bills in full and B: we actually use less energy than previously as we've upgrade our water heater, washing machine and our lights to energy savers. 

When we called we were offered no good explanations for the above or the fact that they're charging us for opting out of having the smart meters which we do have. 

No one has tried to resolve this issue and we continue to fight it.