Instead, their 50:50 joint venture, called Gasbridge, is now focusing on the feasibility of constructing some sort of offshore LNG facility if future domestic gas supplies fall to a level where gas must be imported.

The revised proposal shows Gasbridge could still be capable of importing up to half New Zealand's annual gas requirements of about 170 petajoules.

"We essentially completed all the work we needed to do to lodge resource consent applications with the relevant authorities but have decided there is now no pressure to lodge those applications," Genesis public affairs manager Richard Gordon told PetroleumNews.net this morning.

He said the gas supply situation had improved since Gasbridge first started investigating the economics of LNG imports about three years ago.

New sources - primarily Pohokura, Greymouth Petroleum's small onshore Taranaki Turangi and Kowhai finds, additional Maui right-of-first-refusal gas and Kupe, which is due onstream in late 2009 - had pushed out the forecasted gas supply gap from about 2014 to 2018 or even beyond.

Gordon said that recent overseas technological advancements regarding offshore LNG plants, some floating, others subsea, now meant it was more cost-effective to develop LNG facilities offshore than onshore.

Many LNG carriers now had their own regasification facilities, enabling them to anchor offshore and regasify their LNG for discharge to shore.

Gasbridge was aware of at least six such offshore LNG facilities around the world - in the United States, United Kingdom and Italy.

The development of offshore LNG facilities was also less expensive and quicker than their onshore counterparts. The Port Taranaki project could have taken four years to complete, while an offshore project would take around 18 months and at half the cost.

However, Gordon added that Gasbridge might still need to file resource consent applications in the future depending how far offshore any regasification facility was and how the gas was brought to shore. Options included pipelines to existing production platforms, onshore pipelines or perhaps tankers to ports.

There was also the possibility that LNG transportation might be necessary if any of the planned frontier exploration in the Great South Basin, or off Canterbury or Northland, struck large gas finds.

"How would you transport the gas to the North Island and the main centres of gas demand?" Gordon asked.

He said the Gasbridge project had not been halted - "we will still keep a watching brief on New Zealand's gas supply situation and overseas LNG developments".

Gasbridge has been monitoring LNG technology developments worldwide, with particular focus on offshore floating options.