Arabian Power Company (APC) has begun commercial operation of its new 1,550MW natural gas CCGT at Umm Al Nar. The project cost around ¥250bn ($2.1bn), and will also produce 110,000t (114 million kilograms) of desalinated water per day. The Umm Al Nar power and water project is 15km east of Abu Dhabi, in the UAE.
The extension has five 218MW gas-fired GE Frame 9351FA turbines with five dedicated heat recovery steam generators (HRSGs). There are two 308MW Toshiba back pressure steam turbines and two Hitachi Zosen desalination units.
GE FRAME F GAS TURBINES
The GE Frame 9351FA turbines are each rated at 218MW gross at site reference conditions. The gas turbines will have dual fuel firing capability, and the five Doosan/NEM HRSGs will have supplemental firing.
The Toshiba single-casing double-flow steam turbines are each rated at 308MW gross and 0.80 power factor. Steam pressure is 88 bar and steam temperature is 566°C. Each turbine will have its own generator. The generator rating is 321MVA with 0.80 power factor.
Two Hitachi Zosen Multi Stage Flush (MSF) desalination units each have a gross capacity of 12.68MIGD. MSF is an efficient, low-maintenance technology. Low-grade steam from the power plant heats tubes inside brine heaters of distiller units. These heat the incoming seawater, which is boiled (flashed) in a low-pressure vessel.
There are several stages, each with lower pressure, with the resulting steam condensing in heat exchanger tubes. MSF is particularly popular in the Middle East because of its reliability, and has low fuel costs when it can use waste process heat.
APC ACQUIRED EXISTING UMM AL NAR
Desalination plants in Abu Dhabi Emirate have been operating near their design capacities and the capital’s power demand is expected to reach 4,500MW by 2010. The privatisation of its water and electricity sector is expected to be complete within the next seven or eight years.
Twelve companies have been formed under ADWEA (Abu Dhabi Electricity and Water Authority). ADWEA formulates policy for managing supply and demand of power and water in the Emirate, appointing the management of ADWEC and Transco, and managing the tendering of contracts to the private sector to supply power and water.
The 12 companies operate commercially, each with its own budget and objectives, under the ADWEA chairman. Four of the 12 companies are involved in power generation: the Al Mirfa Power Company, Umm al-Nar Power Company, Bainounah Power Company and Al Taweelah Power Company.
APC was formed by ADWEA, Tokyo Electric Power Company (TEPCO), Mitsui, and International Power (IPR). The company acquired the existing Umm Al Nar project in November 2002, consisting of several thermal power plants which generate 850MW and have desalination facilities with a daily output of 750,000t (760 million kilograms) of water.
Mitsui is providing a parent guarantee for the EPC contract. IPR and TEPCO are project sponsors and joint operators of the plant. The new and existing facilities are being operated and maintained by an operating company, ITM O&M Company Limited, which is owned 30% by TEPCO and 70% by IPR. The whole plant will produce 2,200MW and 157MGD. The old plant will be retired in 2008.
APC entered into a Power and Water Purchase Agreement (PWPA) in March 2003 with Abu Dhabi Water and Electricity Company (ADWEC) for the supply of Power/Water to TRANSCO. Natural gas for the project is supplied by the Abu Dhabi National Oil Company (ADNOC). All electricity and desalinated water will be purchased by ADWEC, which is wholly owned by ADWEA.
INDOOR ELECTRICAL SPECIAL FACILITIES
The plant extension also includes ongoing construction of indoor electrical special facilities: 400kV grid station, 132kV grid station and connection to an existing 132kV grid station. After completion, the electrical special facilities will be transferred to Transco.