A consortium led by Japan's Marubeni Corporation has proposed the lowest tariff to build a 2,000 MW power plant in Riyadh for Saudi Electricity Company (SEC).

The consortium, which also includes Kansai Electric and Saudi Masader Company for Power, Water and Gas, proposed a levelised electricity cost - which includes costs of production, fuel, financing and operations - of 0.077 riyals per kilowatt hour, Saudi Electricity said.

In a statement on its website Saudi Electricity said it would examine legal and technical aspects of all bids before signing a power purchase agreement (PPA) by the end of March.

'Bids are now under evaluation, within a month or a month and a half we will have a clear picture,' Amr Al-Swaha, head of independent power producer (IPP) projects, told Reuters.

French utility group GDF Suez along with Saudi Al Jomaih Group's offered a cost of 0.1079 riyals per KWH. A bid by Japan's Sumitomo, Tenaga Nasional of Malaysia and Saudi Binladin Group came in at 0.1126 riyals per KWH, the SEC said.

Japan's Mitsubishi Corp, with Saudi Acwa Power and Japan's Tokyo Electric Power, made an offer of 0.1197 riyals per KWH, while International Power with Saudi Oger and Korea Electric Power Corp (KEPCO) made the highest tariff with 0.1299 riyals per KWH.

The combined-cycle plant would use gas and will start its first phase of operation by 2012.

Swaha said in October the plant would cost between $2 billion and $2.5 billion. However, Saudi Electricity Chief Executive Ali al-Barrak said in July the plant was estimated to cost 12 billion Saudi riyals ($3.2 billion).-Reuters