Bord Gáis has received so many queries about its entry into the residential electricity market that it may have to double the number of staff taking calls.

A spokesman for Bord Gáis said that at one stage staff were signing up 1,000 customers an hour, and that by close of business on Saturday an estimated 16,500 people had switched to Bord Gáis.

Marketing activities may be scaled back next week to allow time to add an extra 50 staff to Bord Gáis's customer service team to meet demand.

The spokesman said the level of interest had taken Bord Gáis by surprise. The company had expected to sign up about 2,000 customers a week.

Bord Gáis entered the electricity market on Wednesday with a guarantee that electricity prices would stay at least 10% lower than ESB rates for the next three years, with additional discounts for natural gas customers and those who pay by direct debit.

ESB is unable to respond to the price cut because its rates are set by the Commission for Energy Regulation. However, prices are expected to drop soon in line with falls in the cost of gas and oil.

Airtricity is also planning a national campaign in the coming weeks following its soft entry into the residential market in October last year. It is also offering consumers a 10% discount and is aiming to sign up 500,000 customers over the next five years.

Bord Gáis recently hired Conduit Enterprises to take care of telesales, Counter Products Marketing for field sales and Millward Brown IMS to carry out market research.