Up to 20,000 ESB customers throughout the country are unwittingly facing arrears bills and some have already found their credit rating has been damaged after the company failed to adjust household meters to take account of price rises since 2001.
Customers who pay for their electricity using a token coin meter may have been undercharged by as much as 25 per cent for the amount of electricity they use. ESB's tariffs have risen by 29 per cent since the deregulation of the supply industry in 2001.
The Echo newspaper in Tallaght reports today that the token coin meters have not been adjusted to take account of the higher rates and that these customers are still being charged the 2001 rate.
Some of the customers, many of whom are in low-income households, have sought advice from a Government-funded advice centre because they cannot pay the arrears.
A number of those who contacted the Money Advice and Budgeting Service (MABS) found their credit rating had been affected when they could not pay the arrears owed.
It is understood that talks are taking place between the ESB and MABS so that the credit ratings issue can be addressed as soon as possible.
A spokesman for the ESB confirmed the meters had not been adjusted in line with the company's tariff increase and said that clearing the backlog could take several months.
"ESB is concerned that all customers pay equitable rates for electricity as per published tariffs," the spokesman told the Echo.
"We are therefore reviewing the situation pertaining to customers who pay by token meter in relation to the impact of tariff increases over the past 18 months. It is our intention to contact each of the customers in this group with a view to resolving the situation."
A spokesman for MABS urged customers in difficulty to contact the service for advice.