Businesses in greater Belfast are set to benefit from a price war which is raging between energy suppliers.
Firmus energy has gone head-to-head with Phoenix Gas in a battle to win more clients.
It launched a marketing campaign yesterday to encourage businesses in Co Antrim and Co Down to switch from Phoenix to firmus. The deal is not open to homeowners.
Mark Prentice, general manager of firmus energy, said: "We are offering business customers a 7.5% discount on Phoenix Gas prices for a year, that is on top of the 19% discount Phoenix announced earlier this month."
Firmus, whose main operation is in the North West, has 70 business customers in the greater Belfast area compared to 125,000 Phoenix residential and business clients.
Despite the natural gas market in greater Belfast being opened up to competition in January 2007, firmus has still not introduced a domestic tariff.
It claims that it has delayed a marketing campaign targeting homeowners because the current system only allows 50 customers a week to switch provider.
Mr Prentice said: "To put the problem in context, if only 10% of gas customers in the greater Belfast area wished to change providers, it would take between four-and-a-half and nine years to switch them."
But Phoenix has hit back at firmus stating that in two years just 70 customers have made the switch.
Phoenix was the sole provider of natural gas in the greater Belfast area for 10 years until 2007. The natural gas market in the North West is controlled by firmus and it will be opened up to competition in 2014. A number of groups have called on the utility regulator to review the system which enables customers to switch suppliers.
"In gas specifically, we have been in discussions for several months with potential market entrants (including firmus) regarding a proposal to improve switching systems," said a spokesman for the regulator.
"We are currently considering whether to approve this as we look to determine how such a short-term change would fit with a longer-term plan to establish adequate, robust and cost-effective gas switching arrangements."