Hong Kong gas bills will be lower after 2006 when Towngas switches to natural gas, a cheaper and more environmentally friendly fuel.
The city's largest piped-gas service provider has promised to pass on any savings in the form of rebates after the switch from naphtha to natural gas.
Towngas' basic tariff has remained unchanged for the past seven years.
Details of the cost and construction involved in the fuel switch will be presented at an economic services panel meeting on Monday.
Legislative Council papers show Guangdong Liquified Natural Gas Terminal would, each year, supply about 330,000 tonnes of the gas which would be converted into piped gas.
That is 10 per cent of the terminal's annual throughput and about 60 per cent of Towngas' yearly consumption of naphtha for production of piped gas.