JEDDAH: Saudi Arabia signed contracts worth SR15.68 billion ($4.2 billion) Tuesday for the construction of the Ras Az Zawr giant power and water plant, official Saudi media reported. Abdullah Al-Hussayen, Saudi Arabia's minister of water and power and chairman of state-owned Saline Water Conversion Corp (SWCC), signed a SR9.07 billion deal with a group led by Al-Arrab Contracting Co to build the power plant on the country's Gulf cost, SPA said. The power plant will be completed in 42 months, Samer Arafa, executive vice president of Al-Arrab, told Reuters. The plant has a planned capacity of 2,400 megawatts, will be able to generate up to 2,750 MW, Arafa added. The group includes China's Sepco III Electric Power Construction Corp. The Chinese company and Al-Arrab were awarded the contract in September. The plant will be integrated with a water desalination facility, for which a SR6.61 billion contract was signed with a consortium of South Korea's Doosan Heavy Industries and Construction Co Ltd and Saudi Archirodon Ltd, SPA said. Doosan said in September its contract was worth $1.46 billion to build the water plant, expected to be the world's largest when it comes on stream in 2014. The plant will produce 1.025 million cubic meters of desalinated water per day. The cost of the project is now set below initial estimates of $6 billion, when Japan's Sumitomo Corp was leading a consortium to build and operate the plant. SWCC will take 1 billion liters of the plant's water production capacity. Saudi Arabian Mining Co (Ma'aden) will take 1,350 MW of the project's power, and 1,050 MW will be allocated to Saudi Electricity Co (SEC). In Ras Az Zawr, Maaden and US aluminum company Alcoa Inc are building a $10.8 billion aluminum project, which will be the world's largest fully integrated aluminum complex when completed in 2014. Saudi Arabia has $500 billion in investment opportunities in energy, transportation and education, according Saudi Arabian General Investment Authority Governor Amr Al-Dabbagh.