UPDATE 1-SSE to buy Welsh power station owner

* Says has agreed to buy Uskmouth Power Co

* Buy takes SSE's electricity generation past 11,000MW

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LONDON, Aug 13 (Reuters) - British power giant Scottish & Southern Energy (SSE.L) said on Thursday it had agreed to buy the Uskmouth Power Company from the Welsh Power Group for 27 million pounds ($44.86 million).

Uskmouth Power Company is the owner and operator of a 363MW (megawatt) coal-fired power station near Newport, South Wales.

"It is generally accepted that the UK's current portfolio of coal-fired power stations still have a crucial role to play in keeping the country's lights on and Uskmouth has the flexibility to help meet demand for power over the next few years," SSE's Chief Executive Ian Marchant said in a statement.

SSE, which focuses on gas and electricity production in the UK, said Uskmouth comprises three independent power generating units, each with 121MW of capacity.

The acquisition will take SSE's electricity generation portfolio past 11,000MW for the first time.

Prior to the purchase SSE had 4,000MW worth of coal-fired capacity.

SSE last month said it expects its first-half profit to be siginificantly higher than a year ago. [ID:nLN716603]

The group, which supplies energy to over a million customers in Wales through its SWALEC brand, bought the South Wales-based Abernedd Power Company from BP (BP.L) in May.

Shares in SSE, which have lost a fifth of their value in the last year, were 0.2 percent up at 1120 pence by 1330 GMT, valuing the company at 10.3 billion pounds. ($1=.6018 Pound) (Reporting by Rhys Jones; editing by James Davey)