UK GAS-Prompt prices rise as wind output lessens

LONDON, Sept 6 (Reuters) - British prompt wholesale gas prices rose on Friday morning on expectations of cooler temperatures and weaker wind power output.

* The day-ahead contract was 2.25 pence higher at 23.00 pence per therm by 0845 GMT.

* Gas for immediate delivery was up 1.15 pence at 21.65 p/therm and the weekend contract was 1.75 pence higher at 21.75 p/therm.

* Traders said strong wind output is expected to lessen by the weekend and cooler temperatures are forecast.

* Wind output has almost reached full metered capacity of around 12 gigawatts (GW) over the last couple of days.

* Strong wind output typically curbs demand from gas-to-power plants.

* Peak wind generation is forecast at 10.9 GW on Friday, falling to 6.7 GW on Saturday, Elexon data shows.

* The system is almost balanced with flows forecast at 149 million cubic metres (mcm) and demand at nearly 151 mcm/day, according to National Grid data.

* Flows from Norway through the Langeled pipeline remain low at 7 mcm/day. UK domestic production is slightly higher.

* "We expect (Langeled) to remain at this level until 10 September when flows should drop to zero as Easington will be shutdown until Sept. 24," Refinitiv gas analysts said.

* In the Dutch gas market, the day-ahead gas price at the Dutch TTF hub was up 0.13 euro at 8.20 euros per megawatt hour.

* Benchmark Dec-19 EU carbon contract was 0.08 euro lower at 25.45 euros a tonne. (Reporting by Nina Chestney)