In July 2003, Alba chose Alstom as the engineering, procurement and construction (EPC) contractor to provide Power Station 4 as part of the Potline 5 Expansion Project for its aluminium smelter plant.

At the contract signing ceremony, Alstom chairman and CEO Patrick Kron said that the company “was proud to have gained the support and confidence of Alba for this initiative, which will grant Alstom the opportunity to play an integral part in one of the most important expansion projects that Bahrain has ever witnessed.”
Two years down the road, Alstom is honoured to join Alba in celebrating the inauguration of the Potline 5 Expansion Project and the successful on-schedule completion of this large and complex undertaking.
The Line 5, comprising 336 pots that produce over 300,000 tonnes of aluminium per year, sets demanding requirements on power station operation.
Alstom supplied 650 MW of new generating capacity while integrating an existing Alstom simple-cycle gas turbine type GT13E2 generating unit into the new power station configuration, thus providing a total generating capacity at the power station of 780 MW.
The power station consists of two multi-shaft combined-cycle blocks each of which comprises two Alstom heavy-duty gas turbines type GT13E2 equipped with low NOx combustion systems, two Alstom dual-pressure cycle horizontal heat recovery steam generators (HRSG) and one Alstom dual-pressure single-casing steam turbine. Each gas turbine is coupled to an Alstom totally enclosed water-air cooled 2-pole three-phase generator.
This configuration provides Alba with high operational flexibility, efficiency, reliability and availability with low operating and maintenance costs while maintaining low emission levels for all operating modes. The combined cycle configuration significantly increases the efficiency of the power station by using the hot exhaust gases of the gas turbines to produce steam to drive the steam turbine.
In the combined-cycle process, the compressor of each gas turbine draws ambient air through the filter and feeds compressed air to the combustor. In the combustor the compressed air is mixed with the fuel and ignited.  On ignition the gas expands to drive the gas turbine rotor and the coupled generator to produce electricity.
The exhaust gas is then fed to the HRSG where steam is generated by heat transfer to the boiler feedwater. The pressurised steam from the two HRSGs is then fed to the steam turbine where it expands to drive the steam turbine rotor and the coupled generator to produce electricity. The expanded steam is fed into an air-cooled condenser where it is condensed back into feedwater.
Alstom was awarded the turnkey power station project, including the civil works part, reflecting the confidence Alba had in Alstom’s general contractor capabilities. As an experienced plant integrator, combining both product and plant know-how, Alstom possesses designs and process layouts that have proved themselves time and again in power stations throughout the world. These designs first needed to be adapted to Alba’s specific requirements and this was achieved by a dedicated engineering team, which produced the project-related specifications needed for manufacture and procurement.
As a manufacturer of core components for power stations, Alstom has an intimate knowledge of their designs and their performance in the field. All other components and systems are procured against specification from outside the company.
It was extremely important to Alstom to secure the services of an experienced local civil and construction contractor. We were very fortunate to have found Ahmed Mansoor Al-A’ali Co. (AMA) with headquarters in Manama. AMA provided all the civil works and the erection manpower and its management for the major part of the mechanical and electrical systems. Thanks to AMA’s dedication to the project, synergies developed with Alstom went a long way to ensuring on-time completion.
The air-cooled condenser is one of the key items in the thermal cycle and Alstom was able to obtain the commitment of SPX Cooling Technologies Belgium SA/NV, a company with a long track record for this type of plant. A turnkey contract was agreed and the company’s experience proved to be a valuable contribution to the timely completion of this unit.
With Shaw-Nass Middle East as local supplier of pipe spools and prefabricated piping Alstom was able to establish fast response times to its requirements.
Many other smaller orders were placed with a multitude of Bahraini companies. However the bulk of equipment was imported and the speedy clearance of customs was vital to the smooth erection sequence on site. Where difficulties arose, Alstom was able to rely on Alba to provide immediate and effective support. 
AMA mobilised immediately after contract signature, starting with the preparation of site and the installation of the site facilities and the Alstom site manager was able to move into his office in July 2003. Once established, he went about founding the organisation and infrastructure necessary for such a large undertaking. At the peak time, the total manpower on site reached over 2,300. Safety was given the highest priority on site both by Alba and by Alstom. This emphasis was so successful that today Alstom can look back with pride at achieving zero lost hours due to injury after totalling over 6,300,000 man-hours of work on site.
Following on the tail of the erection activities, Alstom, together with the designated Alba operations staff, began commissioning work, which was so successful that the first combined cycle block could be taken over before schedule by Alba in June 2005.
Right from the very beginning, Alstom was able to install a strong project management team drawn from an arsenal of experienced engineers worldwide. The project manager led dedicated team members covering quality, scheduling/planning, contract management, procurement, transport and engineering coordination. A direct link from the project manager in Switzerland to the Alstom site manager assured rapid coordination. This team ensured that the working processes that have been developed and refined over the years on other power station projects, together with tried and tested working tools, were applied in a manner such that all the project targets were met in respect of quality, schedule and contractual fulfilment.
Finally, with the Alba project team, supported by its engineer Mott MacDonald, Alstom found a cooperative counterpart whose striving spirit to “get it right” supported us in many situations. It is the knowledge of having achieved the targets together that gives Alstom the feeling of truly sharing Alba’s success.