Bord Gáis has also been overcharging a small number of customers.
A review by the state-owned energy supplier shows it has undercharged 57,000 pay-as-you-go customers for the gas they have used. No discrepancy was found among Bord Gáis electricity customers.
The prime cause of the undercharge stems from the incorrect application of a gas price increase of 21.72%, approved by the Commission for Energy Regulation from Oct 1. In the case of pay-as-you-go customers, Bord Gáis applied a 10% increase in error. The proper increase will be applied from today.
According to Christine Heffernan, Bord Gáis head of public relations, the undercharge amounts to an average of €59 for each pay-as-you-go customer, working out at about €12 per month.
“€3.3m is the amount of revenue undercharged,” she said. “It is an issue we have addressed and we have now put a fix in place.
“We will be sending out letters from tomorrow to those 57,000 customers who represent around 11% of our gas customer base.”
A significant number of that number comprise customers who had fallen into arrears with their bill-pay accounts and opted for meter billing.
Insisting that the computerised billing system was “state-of-the-art”, Ms Heffernan said human error was to blame for the misapplication and last night promised that the underpayment would be absorbed by Bord Gáis and not passed on to customers.
“The misapplication of the price increase to pay-as-you-go accounts arose because the process requires a manual intervention to update prices on the pay-as-you-go system,” she said. “Unfortunately, human errors were made in the price update instruction process, which have led to the undercharging of customers on pay-as-you-go meters.
“In view of the fact that the fault for the error lies entirely with Bord Gáis, the company will not be asking pay-as-you-go customers to pay for the undercharge to their accounts and will absorb the full costs.”
Larry Donald, Bord Gáis director of corporate affairs, said the error took some time to emerge due to the two-month billing cycle applied to customer accounts.
“We found that we had more revenue expectation than we were getting,” said Mr Donald. “When we investigated, we identified the pay-as-you-go system as the source, which meant having to go through each of those 57,000 accounts. We then found that, because of the mistake made, that some customers were getting more consumption than they were paying for.”
Mr Donald added that the investigation also revealed that 170 gas customers had been overcharged by €51 each and would be reimbursed in a manner of their choosing.
Ms Heffernan said that those overcharged would also be telephoned to explain the error.
“We have made mistakes and are being up-front with our customers,” she said.