In November last year, VA Tech was awarded a contract to supply and install new gas insulated switchgear bays at a substation in Qunfudah, Saudi Arabia. The installation will help the Kingdom evacuate power in the face of rapidly growing demand.
In the Middle East there has been impressive and consistent economic growth during the last decade. The power generating industry has also seen a consistent growth each year and many plants have been or are currently under construction to meet increasing demand. In Kingdom of Saudi Arabia, one of the fastest growing power markets in the Middle East, extensive work in the area of power transmission and distribution are currently in progress in order to match the increasing generating capacity.
Figure 1. VA Tech is supplying five 132 kV gas insulated switchgear bays (GIS)
Currently the Kingdom has 240 000 km of transmission lines. However, at present, some 20 per cent of the Saudi Arabian population is unconnected to the national grid. As it stands, only two of the country’s four regions are connected and it is estimated that an additional 32 000 km of transmission lines is necessary to create a unified grid.
Saudi Arabia’s young population has nearly tripled since 1980, an increase that has seen Saudi Arabia become one of the fastest growing nations in the world. Combined with artificially low power prices – a result of low, government mandated tariffs and consumer subsidies – there is now an increasing demand on electric utilities with power demand growing by 5-7 per cent or more each year.
Saudi Arabia’s Industry and Electricity Ministry estimates that the country will need up to 70 000 MW of power generating capacity by 2020 compared to its current capacity of 25 000 MW. This new capacity will cost in excess of $110 billion. Most of this will need to come from the private sector, possibly including foreign investors.
The vast majority of this capacity will be natural gas-fired combined cycle (about 65 per cent), as part of the government’s plans to expand gas utilization in the power sector. However, companies that are investing will have to contend with a market in which new industrial projects have been delayed and brownouts have occurred due to inadequate power supplies, especially during the summer peak cooling demand season.
In an attempt to meet this demand, Saudi Arabia decided to begin restructuring its power companies and alter the rules surrounding private participation in the power sector. In 2000, Electricity Minister Dr. Hashem Ibn Abdullah Yamani signed a merger agreement between Saudi Arabia’s ten existing power companies, establishing the long anticipated Saudi Electric Company (SEC), a joint-stock company, of which the Saudi government control 50 per cent.
The creation of SEC has opened the door to private sector construction of new power plants on a BOT (Build-Own-Transfer). However there are still major challenges that lie ahead, including: tariffs, legal and operating framework, taxation, and fuel supply.
Delivering the demand
In addition to increasing generating capacity, the SEC is undertaking 11 transmission projects in order to upgrade and expand the domestic power grid at a total cost of about $2.2 billion.
As part of the effort to improve the network south of Jeddah, VA Tech T&D recently secured a new contract from Saudi Electric Southern Operating Area (SOA) in Qunfudah. The contract, worth approximately g5 million ($6.7m), is to supply and install on a turnkey basis five 132 kV gas insulated switchgear (GIS) bays as well as a 13.8 kV switchboard and two transformers in the existing substation in Qunfudah, including all accessories such as relay and control panels, auxiliary transformers, etc. The new switchboard will improve the local distribution. The existing transformers will be replaced with larger transformers.
Figure 2. Typically, GIS takes one third of the space of air insulated switchgear
Saudi Electric SOA awarded the contract to VA Tech T&D due to its experience of extending the existing substations with limited space and operating restrictions with minimum disruption to the electrical system.
Peter Hall, the project manager at VA Tech commented: “It is not our biggest project but it is a logistical and applications challenge since we are working on an existing live site in limited space.”
VA Tech will insert five bays of GIS between two existing bays of air insulated switchgear (AIS). “We have to fit five bays of GIS into a small space. But we have a compact design which allows us to achieve this. Also, GIS was chosen because of the harsh environment, which has a lot of airborne sand,” said Hall.
Typically GIS takes one third of the space of air insulated switchgear. Also, VA Tech claim that the TH7m GIS, to be installed at Qunfudah, is designed to drive down the cost of the substation through reduced capital investment costs, including the costs of studies, civil works, erection and commissioning. The company believes that operating costs will be reduced due to lower maintenance costs and improved availability.
Figure 3. The logistics presented VA Tech with its biggest challenge of the project
VA Tech has minimized footprint size on the TH7m through the use of computer aided-design and visualisation tools that allowed various arrangements to be tried and eliminated at an early stage of product development. Size savings are achieved by:
à¢€¢ Integrating circuit-breaker and disconnector functions into a single unit. The isolating capability of the unit has been verified by dielectric testing following a full electrical endurance test programme simulating 30 years of typical operational life;
à¢€¢ Disconnector and earthing-switch functions are also integrated. The intermediate position, where both the earthing switch and the disconnector are open, can be verified through a viewing port;
à¢€¢ Control, monitoring and protection are integrated at bay level.
All these result in the total weight of the bay being less than three tonnes.
Civil works is scheduled to start within the next month or two. VA Tech is currently carrying out detailed engineering work. This will be submitted for the necessary approvals by the Sceco engineers to ensure the company is happy with the chosen solution.
The Qunfudah project is scheduled for completion in April 2006 and although small, underlines VA Tech’s expertise in carrying out logistically challenging projects and demonstrates its commitment to the region. For example, just north of Saudi Arabia, in the kingdom of Jordan, the National Electric Power Company (Nepco) awarded VA Tech a project valued at g23 million. The scope of the project is to supply and install a new 400 kV GIS substation in Samra, Jordan. The contract, which will be handled on a turnkey basis, includes six bays of 400 kV GIS switchgear. The substation will be commissioned in July 2005. VA Tech has so far supplied three out of the five Nepco 400 kV substations, including both of the Nepco GIS 400 kV substations, and have played a significant part in the restructuring of the power sector in Jordan since 1999. MEE