Located at an oil refinery on Norway's west coast, the Technology Centre Mongstad aims to test French and Norwegian methods of capturing carbon dioxide emissions and burying them underground to prevent them from escaping into the atmosphere.

"We need to find a way to reconcile the need for energy and the need for emission reductions," said Prime Minister Jens Stoltenberg as he inaugurated the site.

"Carbon-capture technology is a key," he said, adding: "This technology may deliver up to 20 percent of the emission reductions needed by 2050."

Built at an estimated cost of 5.9 billion krone ($1 billion) mainly with state funds, the Mongstad centre is "the world's largest and most advanced laboratory for testing carbon-capture technologies",
Stoltenberg said.

The centre is three-quarters owned by the state firm Gassnova, followed by a 20 percent stake held by Norway's Statoil, with the Anglo-Dutch Shell and South Africa's Sasol holding the remaining stakes.

It is testing technologies of the French company Alstom and those of Norway's Aker Solutions.

Stoltenberg launched the ambitious project in 2007 with the aim of making Norway a world leader in capturing and storing carbon dioxide, a goal he likened in importance to a Moon landing.

But the project has been plagued with delays and cost overruns: the goal of large-scale capture and storage of the carbon dioxide emitted by Mongstad's refinery and natural gas processing plant was initially set to enter operation in 2014, but is now expected to become possible in 2020 at the earliest.