With its 2,745-megawatt power capacity and desalination output of 800,000 cubic meters per day, the project is the world's most notable integrated water and power facility (IWPP).
Jubail IWPP Plant is a joint venture between Marafiq, Saudi Electricity Company (SEC), the Water and Electricity Holding Company, and the SGA Marafiq Consortium comprising ENGIE, Gulf Investment Corporation, and ACWA Power Projects.
The plant is a dual-purpose facility, with combined-cycle based power and MED water generation. There are four power blocks – three blocks, each comprising three gas turbines, one back-pressure steam turbine and nine MEDs, and one block containing three gas turbines and one condensing steam turbine.
The power plant uses natural gas as the primary fuel with high-speed diesel as a back-up. In combined-cycle operation, excess heat from the gas turbine exhaust is fed into heat recovery steam generators, or HRSGs, to make steam to generate additional electricity via the steam turbines. This enhances the efficiency of electricity generation from the plant.
Extraction steam from the steam turbines is supplied to the desalination plant as process steam. The water facility consists of 27 desalination units using the latest Multiple-Effect Distillation (MED) technology with Thermal Vapor Compression (TVC). This is a thermally driven process that involves heating seawater to boiling through multiple stages at successively lower pressures. The produced vapor is condensed in the downstream stage to form distilled water. The process achieves good use of the input thermal energy, delivering 9.85 tons of product water for each ton of steam consumed. The distilled water is re-mineralized to meet the quality standards for specified product water.
The plant is owned by Jubail Water and Power Company (JWAP). The off-taker is Marafiq Water and Supply Company (Tawreed), a wholly-owned subsidiary of Marafiq, which purchases all of the plant output through a 20-year Power and Water Purchase Agreement (PWPA) with JWAP. The entire power output of the plant is supplied to SEC while JWAP, through Tawreed, supplies (300,000 cubic meters) to Marafiq for distribution in Jubail Industrial City and (500,000 cubic meters) to the Saline Water Conversion Corporation (SWCC) to supply other parts of the Eastern Province.