2. General situation in Thailand’s electricity sector
Electricity is one of the necessities in the ordinary business of
life, and a major driving force for world economic growth and
development, Thailand without exception. With un-storable
nature of electricity, the supply of electricity must always be
available to satisfy the growing demand. Since 1968, Thailand
electricity supply services have all been taken over by the state
government and operated under state enterprises under a law
empowering its monopoly. The state utilities accumulated assets
and built up their manpower to expand and operate the power
system to serve the whole country [6]. Thai power system has a
single buyer structure that the Electricity Generating Authority of
Thailand (EGAT) currently provides about 53 percent of the
country’s electricity supply. EGAT plays the main role not only in
generating country’s electricity but also in operating all high
voltage transmission lines and monopolizing the buying power of
the country’s electricity [7]. EGAT sells bulk power to two
distribution utilities; (a) the Metropolitan Electricity Authority
(MEA) responsible for the sale of electricity within Bangkok and
surrounding areas; and (b) the Provincial Electricity Authority
(PEA) responsible for electricity sale in the remaining parts of the
country. Additionally, private power producers sell electricity to
the electric utilities under power purchase agreements or to users
located nearby. Since early 1990s when high growth in power
demands existed, the government developed several initiatives to
privatize state electric utilities and engage independent power
producers (IPPs) with long-term power purchase agreements
(PPAs) for supply of electrical power into the grid system (Fig. 2).
4.7. Geothermal
Geothermal energy is natural energy from the internal heat of
the earth; the temperature varies with respect to the distance from
the earth surface (geothermal gradient) – the deeper from the
earth surface, the higher temperature. At the depth of about 25–
30 km, the average temperature will be around 250–1000 8C. There
are approximately 64 geothermal resources in Thailand, but major
ones are in the northern part of the country, especially the geyser
field at Fang District in Chiang Mai Province. Currently, EGAT is
operating a 300-kW binary cycle geothermal power plant at Fang
District, generating electricity at about 1.2 million kWh per year,
which helps reduce oil and coal consumption for power generation.
In addition, other benefits derived from the waste heat of hot
water used in the power plant. The temperature of hot water, after
being used in the power plant, will decrease from 130 8C to 77 8C,
which can be used for drying agricultural products and feeding the
cooling system for EGAT’s site-office space. Some other non-energy
uses of hot water from geothermal sources are for physical therapy
and tourism [24]. Due to limited geothermal resources in the
4.7. Geothermal
Geothermal energy is natural energy from the internal heat of
the earth; the temperature varies with respect to the distance from
the earth surface (geothermal gradient) – the deeper from the
earth surface, the higher temperature. At the depth of about 25–
30 km, the average temperature will be around 250–1000 8C. There
are approximately 64 geothermal resources in Thailand, but major
ones are in the northern part of the country, especially the geyser
field at Fang District in Chiang Mai Province. Currently, EGAT is
operating a 300-kW binary cycle geothermal power plant at Fang
District, generating electricity at about 1.2 million kWh per year,
which helps reduce oil and coal consumption for power generation.
In addition, other benefits derived from the waste heat of hot
water used in the power plant. The temperature of hot water, after
being used in the power plant, will decrease from 130 8C to 77 8C,
which can be used for drying agricultural products and feeding the
cooling system for EGAT’s site-office space. Some other non-energy
uses of hot water from geothermal sources are for physical therapy
and tourism [24]. Due to limited geothermal resources in the