With its 2,745 megawatt power capacity and desalination output of 800,000 cubic meters per day, the IWPP in Jubail is the world’s largest integrated water and power facility.

The plant is a joint venture between Marafiq, Saudi Electricity Company (SEC), the Public Investment Fund of the Ministry of Finance, and the international Suez Consortium comprising Suez Energy International of Belgium, Gulf Investment Corporation of Kuwait and ACWA Power Projects of Saudi Arabia.

The primary fuel is natural gas with high-speed diesel as back-up fuel. The plant is a dual-purpose facility, with the power plant based on combined-cycle generation. There are four power blocks – three blocks each comprising three gas turbines and one back-pressure steam turbine, and one block comprising three gas turbines and one condensing steam turbine. The power plant uses natural gas as primary fuel in a combined-cycle generation process, in which excess heat from the gas turbine generators 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 to over 60 percent, as opposed to the usual 50 percent in conventional plants.

Extraction steam from the gas turbines is also 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 sea water 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 tones of product water for each ton of steam consumed. The distilled water is re-mineralised to meet the quality standards for specified product water.

The operation of the plant is managed by Jubail Water and Power Company (JWAP). The off-taker of the project is Tawreed (Marafiq Water and Supply Company), a fully owned subsidiary of Marafiq, which manages the Power and Water Purchase Agreement (PWPA) with JWAP. The entire power output of the plant is supplied to SEC. JWAP, through Tawreed, supplies 37.5 percent of the daily water production (300,000 cubic meters) to Marafiq for distribution in Jubail Industrial City. The Saline Water Conversion Corporation (SWCC) takes up the other 62.5 percent (500,000 cubic meters) to supply other parts of the Eastern Province.