By Catherine Airlie and Ben Farey

Feb. 4 (Bloomberg) -- U.K. natural-gas contracts rose as exports from Norway’s two biggest plants were reduced because of bad weather and erratic power supplies.

“The processing plants at Kaarstoe and Kollsnes have had a loss in power supply due to bad weather conditions, and are now reduced,” Lisbet Kallevik, a spokeswoman for Bygnes, Norway- based Gassco AS, said today in an e-mail.

Exports from Kollsnes were reduced to about 50 million cubic meters a day at 11:30 a.m. local time, Kallevik said, adding that “the rate is changing all the time, since we are ramping up now.”

Norway is the biggest foreign gas supplier to the U.K. and the second-biggest exporter to Europe after Russia. Both Kollsnes and Kaarstoe send fuel via subsea pipelines to markets in mainland Europe as well as Britain.

Gas for delivery in the U.K. next month rose as much as 0.9 pence, or 1.7 percent, to 55.6 pence a therm. The contract was at 54.8 pence at 4:30 p.m. in London, according to broker prices on Bloomberg. That’s equal to $8.92 a million British thermal units and up 3.4 percent on last week, the first gain in five.

The summer contract was little changed at 53.6 pence.

National Grid forecast gas demand at 321 million cubic meters in the 24 hours through 6 a.m. tomorrow, about 36 million below normal for the time of year. The nation’s pipelines will hold 352 million cubic meters of gas at that time, about 3 million more than at the start of today.

U.K.-Belgium Pipeline

Natural gas for same-day delivery gained 0.6 pence, or 1.1 percent, to 55.35 pence a therm. That’s 1.1 pence higher than yesterday’s forward price for today.

Interconnector (U.K.) Ltd., owner of a reversible natural- gas pipeline between Britain and Belgium, switched flow direction to U.K. exports at 8 p.m. yesterday after importing since Jan. 19, according to information on its website. It reverted to imports again at midday.

Gas for next working day delivery was at 54.5 pence at 4:30 p.m. Demand usually rises after the weekend as factories and businesses ramp up operations. About half of Britain’s electricity comes from natural gas-fed power plants so prices are affected by fuel costs.

U.K. baseload power for Feb. 7 rose 56 pence to 46.01 pounds a megawatt-hour. Baseload is delivered round the clock. Bloomberg data is compiled using prices from brokers including ICAP Plc, GFI Group Inc. and Spectron Group Ltd.

--Editor: Rob Verdonck

To contact the reporter on this story: Ben Farey in London at bfarey@bloomberg.net

To contact the editor responsible for this story: Stephen Voss on sev@bloomberg.net

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