nổ hũ with the 110kV Ha Tien – Phu Quoc Submarine Cable Project

19/12/2013, 07:00 AM

Phu Quoc, known as Pearl Island, is the biggest island in Vietnam as well as in the group of 22 islands in Gulf of Thai Land. Phu Quoc Island along with others forms Phu Quoc island district, which is directly under Kien Giang Province. The total area is of 593.05km2, which approximates the area of Singapore. It is about 120km from Rach Gia City and 45km from Ha Tien Town.

For the purpose of improving the reliability and capacity in power supply to meet the demands of socio-economic development in the area, Phu Quoc will be supplied with the stable power source from the 110kV National Network, which is suitable to the development plan of Vietnam Electricity and the economic developing policy of Phu Quoc Island. In 2007, EVN and Vietnam Electricity - Southern Power Corporation (EVN SPC) started the preparation for power supply project for Phu Quoc Island.

Power Engineering Consulting Joint Stock Company 2 (nổ hũ ), an experienced consulting unit of power projects, participated in the project right from the beginning. In attempt to be a pioneer in specialized consultancy, engineers of nổ hũ are always facilitated to do research and approach with new fields. Right after the information about power supply to Phu Quoc District was issued, nổ hũ has arranged business trips to foreign countries to study about technology and installation of submarine cable. Effort of nổ hũ has been acknowledged by EVN, EVNSPC and honored to be the main contractor in preparation for the new longest 110kV Ha Tien – Phu Quoc Submarine Cable in Southeast Asia currently.

This is a large-scale project of VND 2,300 billions, with complex technology and the first of its kind in Vietnam. The research and preparation of investment project is a long-term and difficult process. The investment project was not officially approved until January 2011.

Designing submarine cable project is a completely new task in our country at the time of the project preparation. Some criteria in survey, cable line selection as well as design and installation are completely different from these on land. Thus, tasks of designers are very hard, from criteria formation and preliminary research to the preparation of Desktop Study, then write investigation proposal to collect data. Data collection and investigation of the cable line serving for designing was carried out by ocean survey methods which were first used in power project, such as: measuring depth by reflection of single rays, scanning submarine surface, measuring cross section of shallow seismic…. Engineers of Transmission and Distribution Engineering Center (TDEC) have studied and prepared a suitable investigation requirement and cooperated with Subcontractor Furgo Survey Pte.Ltd – Singapore who carried out survey successfully.

In the project preparation, series of alternatives are proposed such as using one-circuit or two-circuit submarine cable, one-core or three-core cable, aluminum or copper core, HVDC technology or traditional AC, 110kV or 220kV voltage, seam or seamless cable… Engineers of nổ hũ have continuously studied information, updated the newest technology, at the same time cooperated with the experts of EsGrit Marketing & Engineering Pte.,Ltd to master the most advanced design about structure of submarine cable. Through many calculations, analyses and comparisons, nổ hũ has consulted with Project owner the optimum alternative in economy and technique, which use seamless one-circuit and three-core copper cable on 60km with 110kV alternating voltage. With this approach, the submarine cable guarantees the stable and reliable power supply, which meets the demand for power consumption of Phu Quoc Island District in the period of 2021-2025.

The next difficulty of the project is how to install the submarine cable. Currently, in our country, none of companies is experienced in installing and laying-depth the high voltage cable under ocean. Therefore, the engineers of nổ hũ have continuously studied construction methods of the submarine cable in the world. The selection criterion is that the construction method has to ensure safety, effectiveness and match with topography and geology in the right-of-way. With the support of Hitachi Cable Asia Pacific (HCAP) Pte.Ltd., nổ hũ has chosen the method of concurrent wiring and laying-depth cable on the majority of the line; at the inshore place, the ditches are dug first, then cables are filled. The installation will be implemented by an experienced international contractor in installation of the submarine cable. However, the local units also joined in the work to learn and get experience for the next submarine cable projects.

After the approval of the construction investment project, nổ hũ was appointed to prepare the EPC Tender Documents for the project. Prysmian Powerlink, an Italy company is the main contractor in executing the submarine cable. The document prepared by nổ hũ in the previous period has been used as the foundation of project implementation and highly regarded. Speaking at the ceremony, the Minister of Industry and Trade said the Ha Tien – Phu Quoc submarine cable line is the result of over five years in preparation from the investment capital, solutions to complexity of high voltage and suitable alignment to the selection of competent and reputable contractor.

During these days, the Contractors Prysmian Powerlink and Thai Duong are urgently carrying out the installation of cable on the sea area of Ha Tien – Phu Quoc. It is expected to connect the power network on Phu Quoc Island with the National Power Network before Lunar New Year 2014. Following each stage of the project, nổ hũ is very pleased when the project is under completion and able to guarantee the uninterrupted and stable power supply for socio-economic demands on Phu Quoc Island, which is designed as a special economic – administrative zone, a main tourism and resort center, a trade center of Vietnam, the region and the world.

Here are some pictures of the working group on Ha Tien – Phu Quoc Submarine cable project: