Stormy weather: swells of between 14 and 15 metres are expected
Evacuations under way as storm roars in
Helicopters are evacuating hundreds of offshore workers from the Ekofisk and Valhall complexes today, ahead of an Arctic storm which is due to hit the region tomorrow.
BP plans to shut its 80,000 barrels per day Valhall oilfield from tomorrow night, while ConocoPhillips said it may be forced to shut down five of 16 oil platforms at the Ekofisk oil and gas field complex, seen producing 236,000 bpd.
The Norwegian shelf's biggest operator, StatoilHydro, said it has no plans to shut production, and Norway's Petroleum Safety Authority (PSA) said it did not expect the storm to affect other fields.
"Platforms are being de-manned safely according to plan," PSA spokeswoman Inger Anda said.
Some Ekofisk and Valhall platforms have sunk closer to sea level because the sea floor they stand on has effectively deepened due to reservoir depletion over decades of production. This makes them risky during stormy weather.
"At fields where subsidence is a problem this is standard procedure when waves are this high - and 14-15 metres swells are expected," Anda said.
"They are in a tight situation at Ekofisk and need these precautions because (at some platforms) subsidence has reached six to seven metres over many years," she said.
The Norwegian Meteorological Institute told Reuters that a low pressure system now southwest of Iceland would likely develop into a gale force or storm over the next 24 hours.
It forecasts the storm's biggest waves could reach 20 metres and strongest winds, due to arrive in the oil-rich region tomorrow afternoon, could reach 80 to100 kilometres per hour.
The storm originated in Arctic regions near Greenland, it said, and is growing in strength with the frigid air it brings with it colliding with much warmer air masses over Europe.
"The (Valhall) production shutdown is commencing (tonight)," said BP Norge spokesman Jan Erik Geirmo. "How long it will remain shut is weather-dependent."
BP said it was removing about 150 workers from the Valhall platform by helicopter before the storm.
"Production outages due to adverse weather conditions have been incorporated into the output plans," Geirmo said.
ConocoPhillips has so far declined to comment on implications for production from Ekofisk - on stream since 1971 - where some 600 out of 1400 offshore employees are expected to be sent back to land.
The rest of the personnel will be relocated to other platforms which were built to withstand harsher weather.
The UK Met Office similarly issued a severe weather warning, predicting high winds in the North Sea tomorrow. However companies operating in the UK sector of the North Sea told Reuters they had no plans yet to shut down production there.
"There are no plans to shut down, but we will be monitoring conditions and adjusting work as necessary to maintain safe operations," Simon Tait, a spokesman for US supermajor Chevron said.
Canada's Talisman Energy also said it had no plans to shut in installations but would be monitoring the situation continuously.