Norway’s oil and gas group Statoil reckons it has found the key to a green and profitable future by burying greenhouse gases underground.
Norway’s biggest company operates the world’s only commercial gas platform in the North Sea to separate carbon dioxide (CO2) from gas and reinject it beneath the seabed instead of releasing it to the air.
“The method has enormous potential. Our imagination is the only limit,” said Sleipner platform chief Edvin Ytredal. The storage could prove profitable under planned CO2 emissions trading schemes.
Rising 650 feet above the sea surface with two giant burning flares, the Sleipner gas platform looks like a monster polluter.
But underneath it has been stashing away one million tons of CO2 gas every year since 1996, or the equivalent of the amount produced by about 110,000 Norwegians a year.
An eight-story block houses about 200 workers, a gym, bible study room and a motorcycle club on top of a complex production facility pumping gas from the reservoir, splitting the CO2 from the gas, reinjecting the greenhouse gas back into the seabed and piping the CO2-free gas to Norway and to Europe.
C02 is the main gas targeted by the international 1997 Kyoto pact aimed at cutting emissions of heat-trapping gases blamed for global warming. The pact prompted the European Union to launch the world’s first international emissions trading scheme in 2005.
State-controlled Statoil would like to be paid to bury CO2 produced by big fossil-fuel burners in Europe such as steel plants or coal-fired power plants which will have to cap their emissions.
“If that solution adds up financially, it would be a dream scenario for Statoil,” said Jan Karlsen, Statoil’s senior vice president for gas sales. But he said it was too early to predict the practical and financial viability.
Several obstacles remain -- so far it is unclear whether CO2 reinjection will be an accepted way of getting rid of climate gases as part of the Kyoto mechanisms. It is also unsure what non-EU member Norway’s position in the scheme will be.
And some environmental groups believe CO2 reinjection might be risky, fearing that the gas might leak into the sea and harm marine life. CO2 is a clear, non-toxic gas but can be disruptive in heavy concentrations.
“We are critical because we don’t know whether this is a permanent solution. No one knows whether the CO2 will stay in the reservoir in 100 or 1,000 years,” said campaigner Truls Gulowsen of the environmental group Greenpeace.
“The more we store greenhouse gases away, the bigger the potential climate bomb is and the longer it will take to get rid of the real problem -- the burning of fossil fuels,” he said.
Statoil says there is no sign of leaks from Sleipner -- and that natural gas has stayed below ground for millions of years.
Offshore taxes in Norway, the world’s third biggest oil exporter, pumping about three million barrels of oil per day, are 78 percent. Statoil says it is saving $143,000 every day in CO2 taxes by reinjection.
To cut the CO2 content, Statoil lets a soap-like chemical called amine react with the gas under high pressure, splitting CO2 from the gas and pumping it back into the Utsira reservoir about 3,000 feet below the seabed.
It estimates that Utsira can hold 600 billion tons of CO2. The world’s total human emissions are 23 billion tons a year.
Gas at the Sleipner West field contains up to nine percent CO2 -- almost four times the maximum 2.5 percent limit for sale in the market and forcing Statoil to cut the CO2 content.
Sleipner West is the only commercial CO2-injecting platform in the world, but there are other similar experimental projects, including in the United States.
Statoil’s giant Snoehvit natural liquified gas project in the Barents Sea is due to come on stream in 2006 with the same technology. And environmental authorities recommend that any future Arctic development should have CO2 reinjection.
Even with CO2 reinjection, there is always a certain amount of emission. At Sleipner, the two flares are constantly burning for security reasons -- in case of a leak, the gas will be burned instead of being released to the air.