London (Platts)--6Dec2012/919 am EST/1419 GMT

Prompt prices eased on the UK power market Thursday as greater expected nuclear and wind output was met by softer NBP gas prices, market source said.

On the OTC market, day-ahead baseload was last heard before midday at GBP50.50/MWh, down from Wednesday's GBP54.50/MWh, while peakload power eased back from GBP61.90/MWh to GBP50.50/MWh.

A trader said that for the majority of the morning the day-ahead baseload contract traded at GBP51.30/MWh but fell following a bearish outturn of GBP50.72/MWh on the N2EX day-ahead baseload power auction.

Friday peak daily power demand is forecast lower at 53 GW from Thursday's 54.9 GW and will be met by rising wind generation and potentially greater nuclear output.

Thursday wind generation levels hovered around the 3.2 GW mark midday but are forecast to reach highs of 3.7 GW at the same time Friday while nuclear generation is expected to be bolstered from its 8 GW levels with the expected return of the Hinkley Point B-3 nuclear unit Friday, according to EDF Energy data.

In addition, the UK within-day and day-ahead were both valued around 69.00 p/th midday, compared with a 70.55 p/th day-ahead close the previous day, and weighing on power prices.

Gas-fired generation on Thursday increased its share to meet higher demand to around 16 GW or 32.6% of the energy mix midday although coal-fired power remains dominant at 20 GW or 40.2%.

Continental power imports remain negligible.

Further out along the prompt weekend baseload was valued lower at GBP49/MWh while weekahead power fell to GBP52.75/MWh.