1. Introduction
1.1. Thailand’s transport sector
Population growth and economic development have caused
increasing demand of travel and freight transport in the country.
Energy demand and greenhouse gas (GHG) emissions in transport
sector have increased dramatically since Thailand began transforming
its agrarian-based economy to an industrialized one.
Because of rapid development of transport infrastructure, especially
road transport, during the past three decades, nowadays,
Thailand heavily relies on energy-inefficient transport modes. Passenger
transport, both in urban area and inter-city, is mostly made
by private passenger vehicles. The urban passenger transport share
by private vehicles, including private cars, pick-up trucks and
motorcycles, around 90%, while less than 10% are made by public
transport [1,2]. The inter-city transports are made by passenger
cars (57%), buses (35%) and small proportion of rail and plane
about 7% and 1%, respectively [3]. Additionally, more than 83% of
long-distance freight transport around the country is done by
trucks [4], which is the highest energy intensity among various
transport modes.
Thailand is also one of the high private vehicle ownership
developing countries. In 2007, the overall private vehicle ownership
is 370 vehicles per thousand persons, which included car
and motorcycle ownerships of 126 and 244 vehicles per thousand
persons, respectively [5].
Due to the use of these energy-inefficient transport modes, the
transport sector consumed large amount of energy every year. In
2007, this sector used 23,615 kilo ton of crude oil equivalent (ktoe),
accounting for about 36.4% of the total final energy consumption in
Thailand [6]. Presently, the transport sector is the second largest of
energy consumed sector.
Since Thailand has few of oil reserves, thus almost of crude oil
and petroleum products have to import from oversea. More than
47 billion liters of imported crude oil and petroleum products [7]
cost Thailand $US 22.5 billion in 2007, which accounting for 9%
of the gross domestic product [8]. About 75.7% of the energy was
used in road transport mode, 16.0% in international air transport,