According to the US firm, Facts, the country's power sector will double its generation capacity by 2015 and gas would fuel 62% of power production, with coal accounting for 30.1%.

Last year, gas accounted for 69% of the 108,375 GWh of power generated. Coal contributed 20%.

Facts senior associate, Shahriar Fesharaki, believes "The substantial growth in power generation will call for more coal-fired power, but natural gas will continue to dominate the overall fuel mix."

Fesharaki also states that gas use in the country is expected to grow - on average - around 5.4% per annum until 2015, with a spurt of 6.1% between 2005 to 2010 when IPPs convert from coal to gas-powered plants.

Thailand's Department of Minerals and Fuels has publicly acknowledged that the country has proven natural gas reserves of around 15.6 trillion cubic feet (tcf). This figure is disputed, however, by Unocal who believe that the actual is far higher, around 40 tcf, with another 20 tcf possible.