Following the devastating earthquake and tsunami in Japan, research by Craigs Investment Partners brokers indicates up to 11 nuclear reactors in Japan may be affected; three reactors of Tohoku Electric in Onagawa, one of Japco at Tokai and seven of Tokyo Electric in the Fukushima plant.
The total energy capacity of the 11 reactors is 9.7GW.
Craigs broker Peter McIntyre said it was still unclear what the extent of damage was, with the nuclear safety concerns at the high-profile Fukushima plant in Japan changing almost on an "hour by hour basis".
"While it's still uncertain, we conclude there will be a reduced reliance on nuclear power in Japan, leading to increased gas demand, mainly in the form of lng imports," he said.
Japan, which lacks its own gas production or pipeline supplies, is already the world's largest lng importer.
About 30% of Japan's energy comes from natural gas, 25% from coal and 24% from nuclear, with oil and hydro making up most of the 21% balance.
Mr McIntyre said that in the short term, with up to 9.7GW possibly going off-line, coal, oil and gas fired energy generation would be required to make up the shortfall.
Australia's North West Shelf producer in West Australia has some spare capacity, but in the short term there could also be a redirection of gas bound for Europe.
In the long term, companies able to increase their lng production beyond present contracts could be well placed, including gas producers Woodside Petroleum and Santos and partial producers Origin Energy and Oil Search.
