RIYADH, Dec 21 - State-run Saudi Electricity Company (SEC) (5110.SE) said on Monday it has received bids from five consortiums to build, own and operate a 2,000 megawatt power plant in Riyadh.

The combined-cycle plant, known as PP11, will boost power supply to the capital of the world's top oil exporter and forms part of the utility's $20 billion plan to add at least 10,000 megawatts capacity through six independent power producer (IPP) projects. [ID:nLQ174931]

SEC also has plans to spend $80 billion adding a total of 20,000 MW through 2018. SEC's capacity is around 40,000 MW.

A Dec. 7 deadline for bids was extended to Dec. 20. [ID:nLL40266]

Investments in the project would amount to 12 billion Saudi riyals ($3.2 billion), SEC's chief executive Ali al-Barrak said in the statement, adding the plant would come online in summer 2013.

The gas-fired plant will be built in two phases, Amr Aswaha, head of projects for independent power projects said in July. [ID:nLB240545]

We expect an award by the end of March and a financial close in May, Aswaha told Reuters on Saturday. (Writing by Reem Shamseddine)