Grid lines

A preliminary feasibility study in 1990 showed that a unified grid would bring significant cost savings and improve the reliability of power supplies across the region, as well as helping utilities to keep pace with rising demand for electricity.

It recommended that a body be set up to oversee the project.

However, it was not until 29 July 2001 that the Gulf Cooperation Council Interconnection Authority (GCCIA) was officially established and the finer details and financing for the power network began to be mapped out.

The decision was taken to implement the project in three phases. Phase I would join the systems of Kuwait, Saudi Arabia, Bahrain and Qatar.

Phase II would see the internal interconnection of the UAE and Oman to form the UAE National Grid and the Oman Northern Grid. Under phase III, a line would be run between Saudi Arabia and the UAE, thereby connecting the first two phases, while another would link the UAE and Oman.

The estimated cost of the project, based on the economic conditions in 2003, was: US $1 189 million for phase I; US $300 million for phase II; and US $137 million for phase III.

The GCCIA calculated that the payback period for an investment of around US $1 billion would be less than four years.

With annual electricity consumption in the GCC forecast to jump from 32 GW in 2003 to 94 GW by 2028, the GCCIA estimated that the interconnected grid would save US $3.5 billion worth of capital expenditure on building new capacity to meet this demand.

Phase I in detail

A second study was carried out in 2003 by SNC Lavalin, which plotted the best route for the interconnecting cables. Interested parties were then invited to submit pre-qualifying bids to work on the phase I project.

Some 91 companies and consortia requested pre-qualification forms and 63 were subsequently submitted.

In the first quarter of 2004, 45 parties were pre-qualified to enter bids for the various contracts. Tender documents were then issued in February 2005.

Deals inked

The winners of the tenders were announced in November 2005.

ABB won a US $222 million order to supply and install six 400 kV gas-insulated substations, including switchgear, circuit breakers, transformers and shunt reactors.

A Prysmian/Nexans consortium was awarded a US $343 million contract to install the submarine cables and land cables that would link Bahrain to Saudi Arabia.

The submarine route spans 42 km and comprises six single phase cables, while the underground section stretches across 7 km. The combined weight of the cables required was said to be more than 12 000 tonnes.

Nexans said it would supply one extra-high-voltage cable circuit, made up of 120 km of 400 kV single core self contained fluid filled (SCFF) submarine cables, as well as 24 km of 400 kV single core SCFF underground cables.

In addition, the firm agreed to deliver 47 km of fibre-optic cable, comprising 48 fibres, along with connection accessories such as joints and terminations; an oil pressurising system; and temperature monitoring systems.

Nexans added that, because of the shallow water in the area, a special cable-laying barge would need to be employed and the submarine cables would have to be buried to avoid damage.

AREVA T&D was signed up to deliver a 1 800 MW high-voltage direct current (HVDC) converter station. The station will convert the frequency between Saudi Arabia’s 380 kV 60 Hz transmission grid and the 400 kV 50 Hz backbone power network connecting Kuwait, Bahrain and Qatar.

The unit will enable the transmission of power between the two systems and will consist of three 600 MW converters including thyristor valves, 375 MVA converter transformers, as well as 380 kV and 400 kV circuit breakers.

The French firm was also given the contract to design and build the entire control, protection and automation system for the grid.

The delivery includes the control centre for the interconnection project, which will be equipped with a SCADA and energy management system, based on AREVA’s e-terraplatform software.

The centre is intended to guarantee the efficiency and safety of the power network and enable the recording and billing of energy transactions between the different countries.

On top of that, AREVA T&D was tasked with developing a telecommunications infrastructure spread across 800 km to relay substation information to the control centre, using a fiber-optic high-speed network and backup digital power line carriers.

The combined value of AREVA T&D’s contracts was US $234 million.

The bill for the 400 kV overhead lines totalled around US $280 million and the order was split between Saudi firms, National Contracting Company and Middle East Engineering & Development Company.

SNC Lavalin International was brought on board as the project consultant and supervisor.

The Canadian engineering and construction company had been involved with the project right from the outset, carrying out the preliminary studies and subsequent detailed engineering.

The US $16 million engineering contract included the supervision of the final designs and selection of suppliers, in addition to overseeing all the construction work.

Progress made

The construction work kicked off immediately after the contracts were awarded and the entire first phase is now more than 50% complete. The substations, HVDC converter and control centre are 70-87% finished.

More than half the overhead power lines are in place and 15% of the land and sub-sea cables have been laid. The energisation date for phase I has been set for 24 December 2008.

Phase II was a minor undertaking in comparison to phase I, and this part has already been completed.

The GCCIA was not involved in the execution of that phase. The whole project is set to be wrapped up in 2010.