Alba’s Power Station 5 (PS5) Block 4 project in Bahrain involves the construction of a new 680.9MW combined-cycle power plant (Block 4) to increase the capacity of the existing PS5.

Aluminium Bahrain (Alba) is one of the largest aluminium smelters in the world with a production of more than 1.6 million metric tonnes per annum. It owns five power stations (PS1 to PS5) to support aluminium smelter operations.

The addition of the new block will increase the capacity of PS5 from 1,800MW to 2,481MW.

Alba reached the financial close for the expansion project in November 2022. The environmental and social impact assessment (ESIA) for the PS5 Block 4 expansion was submitted to the Supreme Council for Environment (SCE) to secure an environmental permit in January 2022.

Construction of the PS5 Block 4 project commenced in July 2022 and it is expected to be completed in two years.

The project, which will have an operational lifetime of 25 years, is scheduled to start operations by the fourth quarter of 2024.

Power Station 5 Details

The PS5 is located in the Alba Industrial Estate in Manama, Bahrain. The location is around 1.5km west of the King Hamad Highway.

The Block 4 will be built south of PS5 on a land that was previously used as a construction laydown area for PS5.

The site encompasses around 20,000m2 area.

The PS5, located within the northwest corner of the Alba site, was commissioned between 2019 and 2020. It comprises three Combined Cycle Gas Turbines (CCGTs) in a multi-shaft of 1:1:1 configuration, with H class gas turbine technology.

The gas turbine units operate on natural gas, however, one of the units can be fired on distillate fuel to enable emergency shutdown of the smelter plant in an event of a complete loss of natural gas supply.

PS1 was decommissioned after PS5 began operations, while PS2 is being kept in a black start state for use during emergencies. The use of PS3 and PS4 were reduced to mitigate environmental impact.

PS5 Block 4 Infrastructure and Operations

The original PS5 combined cycle power plant comprises three GE-9HA gas turbines, three steam turbines, and three heat recovery boilers for steam generation (HRSGs).

The PS5 Block 4 will have a similar 1:1:1 configuration with J-class gas turbine technology and a tie-in to the existing 220kV substation.

A 6,000m2 power generation building will house gas turbine halls, steam turbine halls, and heat recovery steam generator (HRSG) halls.

Key infrastructure will include 475.4MW J Class gas turbine, heat recovery steam generator (HRSG), and two-cylinder tandem, single axial exhaust type steam turbine generator producing 217.3MW.

The block will have an electricity generation capacity of 680.8MW. It will operate on 100% Khuff gas and 100% residual, as well as in any proportionate mixture of Khuff-residual gas.

Around 117.059 million metric standard cubic feet per day (mmscfd) of natural gas required for Block 4 operations will be supplied from the existing Alba PS5 gas station.

Electricity required for the construction of Block 4 is estimated to be 4,600MWh and 16,700KW/h during the operation phase, both of which will be supplied by the existing PS5.

Alba’s potable water supply network will meet water requirement for the project.

During peak construction phase, the project will involve up to 1,500 workers who will accommodated in an existing purpose-built accommodation south of the Al Dur Power Station within the laydown yard.

Contractors Involved

Envirotech Consultancy was engaged to undertake environmental and social impact assessment (ESIA) study for the PS5 Block 4 expansion. The company was also responsible for the Construction Environmental and Social Management Plan (CESMP) and Operational Environmental and Social Management Plan (OESMP).

In May 2022, Mitsubishi Heavy Industries’ Mitsubishi Power and SEPCOIII consortium signed a turnkey contract with Alba to design, engineer, procure, construct and commission the 680.9MW Combined Cycle Gas Turbine Power Block.

Under the terms of the contract, Mitsubishi will supply a combined cycle power unit with a M701JAC gas turbine and a steam turbine. The M701JAC turbine is an air-cooled version of J-series gas turbines.

Mitsubishi Power signed a Long-Term Service Agreement (LTSA) with Alba in October 2022 that encompasses repairs and services of PS5 Block 4.

As part of the deal, Mitsubishi will provide its suite of intelligent solutions TOMONI that harnesses big data and provide real-time predictive insights, adaptive control, and actionable knowledge to increase power plant performance and achieve environmental performance goals.