Investor interest in liquefied natural gas (LNG) has surged in recent years, reflecting a happy confluence of trends.

North American oil and gas producers have long coveted LNG exports as a potential release valve for the domestic oversupply of natural gas, a product of the industry’s aggressive drilling in the Marcellus Shale and other prolific unconventional resource plays.

Surging natural-gas production has overwhelmed domestic demand and depressed prices relative to international markets, creating a tantalizing arbitrage opportunity that would benefit North American producers as well as Asian and European buyers.

The appeal of US LNG exports likewise received a lift from demand-side developments in Asia, a market that in 2014 absorbed about 72.8 percent of global volumes, according to BP’s (LSE: BP, NYSE: BP) recently released Statistical Review of World Energy 2015.

Together, Japan and South Korea last year accounted for more than 50 percent of global LNG demand.

These countries rely heavily on imported LNG to meet their energy needs. Not only does a paucity of domestic energy resources force Japan and South Korea to rely on imports, but formidable geographic obstacles—the Pacific Ocean and North Korea, respectively—also prevent these nations from accessing the continental pipeline system.

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Over the past decade, Japan and South Korea have provided a source of steady demand growth, with imports jumping whenever a slug of new liquefaction capacity comes onstream.

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However, the sudden surge in the Japan’s LNG imports in 2011 had nothing to do with the addition of liquefaction or regasification capacity.

In spring 2011, the magnitude-9.0 earthquake and resultant tsunami that devastated Japan’s Tohuku region and crippled the Fukushima Daiichi nuclear power plant prompted authorities to shutter the bulk of the nation’s nuclear reactors.

Two of Japan’s nuclear power plants resumed operation in mid-2012, but all of the nation’s 48 reactors have remained offline since the No. 3 and No. 4 reactors at Kensai Electric Power’s Oi plant closed for maintenance in September 2013.

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To offset the loss of about 30 percent of Japan’s baseload power, the country’s 10 largest electric utilities have stepped up their consumption of coal, heavy fuel oil and LNG.

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With Japan’s LNG imports surging unexpectedly in 2011 and growing further in 2012, the so-called Fukushima effect intensified competition for volumes in the spot market at a time when Chinese demand ramped up rapidly.