Innovation in Global Power - Parsons Brinckerhoff

Transporting Power Across the Grid
http://www.pbworld.com/news_events/publications/network/
Meeting the Need for Reliable, Cheaper and
Nonpolluting Electricity in Cambodia
By Fleur Parkinson, Hong Kong, 852 2963 7640, parkinsonF@pbworld.com; and Jon Roe, Singapore, 65 6290 0615, roeJ@pbworld.com
A major new electricity
transmission project in
Cambodia helped to lower
the cost of electricity significantly
and improve its
reliability and provision in
the northwest portion of
the country. The authors
summarize PB’s involvement
in the project and
discuss the challenges
faced by the project team,
including those related to
performing site work under
adverse conditions.
Figure 1: Route of Cambodia’s
new transmission line in northwest
region.
Cambodia has made considerable progress in reforming its power sector, particularly in
passing the Electricity Law in 2001 and establishing a regulator. The country has had one
of the lowest electrification rates in Asia, however, with only 12 percent of its population
(approximately 14 million) connected to a power supply. In addition, Cambodia has some
of the highest electricity costs in the world.
The main supplier of electricity is the state-owned Electricite du Cambodge (EDC), which is
aided by a few local independent power producers (IPP). Generation is provided mainly by
using diesel generators, so already high costs have increased with rising oil prices. While the
supply of electricity is fairly reliable in the main towns, its high price has led many large
consumers to run their own generators (also diesel). Provincial towns and rural areas rely on
even more expensive and less efficient diesel generating units that provide erratic supply. The
only power in rural areas and in villages along the transmission lines is generated through the
use of car batteries that local entrepreneurs charge by using diesel or petrol generators. The
cost of power in these areas is twice that supplied in the towns, and the discarded batteries
create a hazardous waste issue.
Electricity is the main concern for the development of the private sector as the limited supply
of electricity raises production costs and limits technology development compared with
neighboring countries. One of the country’s key priorities in the medium term is to alleviate
shortages of reliable power and reduce electricity costs in order to help develop its economy
and reduce poverty. To this end, a new transmission project was recently completed that
imports electricity from Thailand to the northwest region of Cambodia.
Transmission Project Overview
Power is imported into Cambodia from the 115/22 kV Aranyaphathet substation located in
Thailand, 15 km (9 miles) from the Thai/Cambodian border. Power is transmitted to the town
of Banteay Meanchey, where the line diverges south and east to supply the towns of Battambang
and Siem Reap (Figure 1). The transmission project aimed to meet the urgent
need of electrical power in all three regional centers. The need was considered
especially great in Siem Reap, however, to support a rapidly growing
tourist industry attracted by the Angkor Wat World Heritage Site. Prior to
energization of the transmission project, a number of newly constructed
hotels in the area relied on in-house generators fuelled by imported diesel.
The project, which will be part of the national grid, includes:
• Three 115 kV/22 kV substations (at Battambang, Banteay Meanchey and
Siem Reap)
• One 115 kV switching station
• Approximately 221 km (137 miles) of a single-circuit 115 kV transmission
line traversing three provinces of northwest Cambodia.
The transmission line uses standard self-supporting reinforced-concrete poles
22 m (72 feet) high, allowing 80-m (262-foot) spans. The poles are inserted
into precast concrete foundations with double-circuit 400 mm 2 (0.6 square-inch)
all aluminum conductor configurations. All line elements follow the standardized
Thailand design for 115 kV transmission lines using concrete poles and
steel lattice towers.
59 PB Network #68 / August 2008