Abu Dhabi sees 732 MW addition

Al Taweelah B, Abu Dhabi`s new 732 MW gas- and oil-fired steam power plant with seawater desalination facility, is nearing completion with five of six units supplying power and potable water. Al Taweelah B required (US)$1,700 million in capital investment from the Water and Electricity Department of the Government of Abu Dhabi.

The ABB Kraftwerke-led consortium erected the power plant, which is equipped with six steam turbosets, each with an electrical output of 122 MW and connected to six desalination lines. In addition to 732 MW of electricity, 76 million gallons of potable water will be produced daily when the facility is complete. ABB supplied the turbines, generators and protection and synchronizing equipment. A separate consortium, ABB Kraftwerke and Babcock-Lentjes was responsible for the steam generators and, with Hartmann & Braun AG, supplied the instrumentation and control system. ABB SAE Sadelmi took care of the mechanical and electrical components. Fisia-Italimpanti supplied and commissioned the seawater desalination units. Civil engineering work was carried out by Six Construct J.V.

The turbines are condensing steam turbines with controlled extraction, each with two single-flow sections, operating with a constant live steam pressure of 93 bar. The steam leaves the boilers at 535 C, where it expands across 29 turbine stages and leaves the HP section with a pressure of only 2.5 bar. At this point, the steam is extracted for the desalination unit. Depending on the operating mode, the remaining steam is directed to the LP section where it expands completely. The generators are 200 MVA class two-pole, air-cooled units. Maximum electrical output at the generator terminals with zero steam extraction is 148 MW and with full heat extraction to the desalination units at a cooling water temperature of 35 C, it is 122 MW. The older plant, Al Taweelah A, has been in operation since 1985 with three 85 MW gas turbines and a seawater desalination plant.