6.6% in oversea water transport, and little was used in more energy
efficiency transport modes, such as rail (0.4%) and inland water
transport (0.4%) [6]. Moreover, this sector was also the second largest
greenhouse gas (GHG) emissions of the total GHG emissions
from energy sector. It emitted about 54.6 million ton of CO2 equivalent
in 2007 [6].
1.2. Policy measures and earlier studies
Because of the dramatic increasing of oil price and environmental
concern, both locally and globally, over the past decade, various
policy measures to curb energy demand from fossil fuels as well as
to mitigate local pollutants and GHG emissions from their utilization
in the transport sector have been introduced and analyzed in
various countries, especially in emerging developing countries as
China and India [9–19]. Among those proposed policy measures,
promoting to use alternative technologies for road transport is an
approach that often proposed for energy demand reduction and
emissions mitigation in short-term to medium-term plans.
The alternative technologies are generally introduced in two
options; fuel switching and energy efficiency options. For the fuel
switching option, the low-carbon content or carbon–neutral fuels,
such as compressed natural gas (CNG) and biofuels, were promoted
as alternative fuel substitute for conventional petroleum fuels. On
the other hand, the energy efficiency option is to improve the energy
efficiency of transport sector by promoting the use of high energy
performance vehicles, such as hybrid electric vehicles, plug-in
hybrid vehicles and electric vehicles.
In Thailand, the government has been promoting bioethanol
and biofuel as alternative transport fuel in the country since
2001 and 2005, respectively. At the end of 2007, annual consumption
of gasohol E10 (gasoline blended with 10% of ethanol by volume)
in Thailand reached 1300 ktoe, accounting for 24% of the
total gasoline consumption, while biodiesel B2 (diesel blended
with 2% of biodiesel by volume) has been sold around 540 ktoe
[6]. In addition, recently, the higher ethanol blended fuel of E20
and E85 have been promoted in 2008 and all diesel sold in Thailand
has been blended with 2% of biodiesel since 2008.
The Thai Government also has promoted the use of high energy
efficiency vehicles. Two high energy performance passenger vehicles
of hybrid cars and eco-cars have been introduced by using
financial incentive measures. The special rate of excise tax and
privilege for investment project were adopted to be an incentive
for automakers to invest in manufacturing of these energy efficiency
vehicles. In addition, other policy measures, such as car
labeling, fuel economy or emission standard, and taxation, are also
being considered.
Several earlier studies, in Thailand, have estimated energy consumption
reduction and/or GHG emissions mitigation in future under
different policy scenarios. Results of those studies presented that
promotion of alternative technologies in road transport, including
promotion of CNG and biofuels as well as improving energy efficiency
of vehicles, have potential to reduce energy related GHG
emissions around 2–10% of the totalGHGemissions in transport sector
by 2030 [20–23]. Even though there are many studies assess the
reduction potentials in Thailand, but most of them not take into account
current policy measures of the Government. Moreover, none
of them assess the possible reduction pathway of the policy measures,
which is critical importance that should be analyzed.
1.3. Context and objective of this study
In this study, in order to analyze the future trends of energy demand
and GHG emissions in Thai transport sector, an econometric
model is developed based on historical information to estimate energy
consumption and related GHG emissions. Two scenarios have
been designed to analyze pathways of energy consumption and
GHG emissions reduction in future under the Thai Government’s
policy measures to promote alternative technologies, including
fuel switching and energy efficiency options, compared with the
baseline business-as-usual (BAU) scenario. Finally, policy recommendation
is given based on comparison of the pathways of energy
consumption and GHG emissions reduction of each alternative
technology options.