"We're seeing an enormous amount of industry interest in Ireland. And we're undertaking a major exploration program," he said. "Hopefully this is the beginning of a renaissance of interest in the offshore arena."
The company, partnered with Exxon Mobil, Repsol and Eni, begins drilling its next well 120 miles off southern Ireland in the coming week.
O'Reilly said the company aims to recover 35 percent of the estimated billion barrels offshore. "So we're looking at a 350 million barrel field off (County) Cork. But that's just one of many basins that we're looking to explore and hopefully exploit."
Three hundred fifty million barrels isn't gigantic. By comparison, the Bakken formation straddling Montana and North Dakota that has many in the U.S. so excited is thought to contain some 18 billion barrels of recoverable oil. Still, it's a lot for a country a bit smaller in size and population than Indiana.
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"We currently import 100 percent of our oil—140,000 barrels a day," O'Reilly said. "The field that we're talking about is prorated at 100,000 barrels of oil per day. That would certainly take a big bite out of the demand in Ireland."
O'Reilly is the son of Sir Anthony O'Reilly, former CEO of Heinz and sometimes called Ireland's first billionaire. The elder O'Reilly is backing Providence, along with JPMorgan, BlackRock and HSBC, among others.
Oil production could lend a boost to Ireland's recovering economy, which grew 0.9 percent in 2012 before sputtering this year. The country is on the mend from the real estate bubble's collapse in 2008 and related banking troubles.