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UK GAS-Prompt prices rise as cool weather boosts demand
(Corrects to read Thursday, paragraph 2)
* Gas plants provide 44 pct of electricity supply
* Market 2.5 mcm undersupplied
LONDON, Sept 2 (Reuters) - Prompt natural gas prices in Britain rose on Wednesday morning as cool weather and low wind power output boosted gas demand from power plants.
Gas for delivery on Thursday was trading at 40.90 pence per therm by 0851 GMT, up 0.70 pence from its previous settlement.
The within-day contract rose 0.40 pence to 40.80 pence per therm.
With supply flows at 217.2 million cubic metres (mcm) per day and demand expected at 219.7 mcm, the system was 2.5 mcm undersupplied, National Grid (LSE: NG.L - news) data showed.
Wednesday's demand was around 44 percent above the seasonal norm of 152 mcm, the data showed, largely due to high demand for gas from power plants.
Britain's Met Office said temperatures would average around 15 degrees Celsius on Wednesday and 14 degrees on Thursday.
Gas plants provided 44 percent of Britain's electricity on Wednesday morning, National Grid data showed, as gas generation made up a shortfall in other types.
Three of Britain's sixteen nuclear reactors are currently offline due to maintenance and refueling while peak wind output in the country is expected to reach 2.3 gigawatts (GW) on Wednesday and 4 GW on Thursday, compared with a maximum capacity of around 8.4 GW.
Analysts at Thomson Reuters Point Carbon said prompt prices were also supported by an expected dip in UK Continental Shelf gas supplies due to maintenance this week.
Centrica (LSE: CNA.L - news) 's North Morecambe gas sub-terminal is due to undergo a full site outage for planned maintenance from Sept. 3- Sept 28.
An unplanned outage at the sub-terminal, which cut flows to zero on Tuesday, ended early on Wednesday morning, Centrica (Amsterdam: CC8.AS - news) said.
In the Dutch TTF gas market, prices were also lower. Day-ahead TTF gas was down 0.10 euros at 19.70 euros per megawatt hour.
In Europe's carbon market, benchmark EU Allowances (EUA) were up 0.03 euros at 8.05 euros per tonne. (Reporting by Susanna Twidale; editing by Jason Neely)
