A KSAT 12 Defenders follow-up investigation found that CPS Energy estimated more than six times as many customer bills in 2012 versus the year before.
Complaints continue to come in to the KSAT 12 Defenders about the utility’s practice of estimating bills rather than reading meters.
In January, Stephanie Fiebrink, a disabled woman who lives in a two-bedroom apartment, came forward to say she was shocked at her high electric bill.
"We turned on the heat one day and that was when we were having that major freeze and we keep it at 50," Fiebrink said.
Jose Garcia, who had an $88 bill the previous month, also complained when he opened the next month's bill.
"When I opened (it), I said, 'Oh my God.' I said, 'From $88 to $403,'” Garcia said. “I said, 'That can't be.'"
Both customers were victims of bill estimating.
CPS Energy underestimated their previous bills and then caught up to reality with a meter reading.
CPS Energy’s Lisa Lewis explained that is how it is supposed to work.
"We usually underestimate, as opposed to overestimate, so ideally we don't overcharge you initially and then have to correct," Lewis said.
Now CPS Energy has released figures showing that during the last part of 2010, the utility estimated about 2,525 bills per month.
In 2011, that average increased to 6,379 per month.
Then last year, that average skyrocketed to 43,161 per month.
Christine Patmon of CPS Energy said it was because of a manpower issue last year that is now resolved.
"We had a situation of where we had some contractors who we had to renegotiate a contract with and so we were down some manpower," Patmon said.
But she said there are no plans to stop underestimating bills to avoid the next month catch-up scare.
"In all fairness to our customers, we don't want to overestimate,” Patmon said.
For customers who want to know what their bill will be like every month, they can get on the budget payment plan.
That way, all twelve months are equal payments.
CPS Energy is moving toward automation, so one day, meters will be read accurately, even at a distance.