GEOTHERMAL ENERGY AND IT’S PROSPECT
IN BANGLADESH
Md. Bodruddoza Mia
1
PhD student, Geothermics Lab.
Kyushu University
And
Lecturer, Dept. of Geology, DU
DEFINITION: GEOTHERMAL ENERGY!

WHAT DOES THE WORD "GEOTHERMAL" MEAN?
Geo = Earth, Thermal = Heat

WHAT IS GEOTHERMAL ENERGY?

Energy that can be extracted from the heat in the earth

Conditions are most favorable for geothermal activity where the earth's
tectonic plates collide and one slides beneath another.

The best example of these hot regions is the Pacific Ring of Fire
Pacific
Ring of fire
2
GLOBAL GEOTHERMAL SITES
3
HOW DOES GEOTHERMAL HEAT GET UP TO EARTH’S
SURFACE?

Conduction and Radiation: Heat from the Earth’s interior flows outward. It is
transferred to the outer layer of rock or the crust.

Convection: In some regions, the mantle beneath the crust may be hot enough to
partly melt and create magma. Magma rising upward out of the mantle can bring
intense shallow heat into the crust.

Rainwater seeping downward through pores and crevices in the crust to depths
of a mile or more is heated. The heated water may be stored at depth in
geothermal reservoirs, or the hot water may flow upward out the reservoirs to
the surface as hot springs, or boil near the surface to create geysers, fumeroles,
and mudpots.
4
TECHNOLOGY VS. TEMPERATURE
Reservoir
Temperature
Reservoir
Fluid
Common
Use
High Temperature
>220oC
(>430oF).
Water or
Steam
Power Generation
Direct Use
Intermediate
Temperature
100-220oC
(212 - 390oF).
Water
Low Temperature
50-150oC
(120-300oF).
Water
Power Generation
Direct Use
Technology
commonly chosen
•
•
•
•
•
Flash Steam
Combined (Flash
and Binary) Cycle
Direct Fluid Use
Heat Exchangers
Heat Pumps
•
•
•
•
Binary Cycle
Direct Fluid Use
Heat Exchangers
Heat Pumps
•
•
Direct Fluid Use
Heat Exchangers
Direct Use
5
Geothermal Power Generation
•World production of 8 GW
2.7 GW in US
•The Geyers (US) is
world’s largest site
-Produces 2 GW
•Other attractive sites
Rift region of Kenya,
Iceland, Italy, France,
New Zealand, Mexico,
Nicaragua, Russia,
Phillippines,
Indonesia, Japan
6
USES OF GEOTHERMAL ENERGY IN THE PAST?
Bathing: Ancient civilizations used hot springs for
bathing
 Medical Therapy: Early Romans used geothermal
water to treat eye and skin disease
 Cooking: Native Americans and others used
geothermal water for cooking
 Heating: Early Romans used geothermal water to heat
their homes in Pompeii

7
DIRECT USES OF GEOTHERMAL ENERGY IS
APPROPRIATE FOR SOURCES BELOW 1500C
•
•
•
•
•
•
•
•
•
Space heating
Air conditioning
Industrial processes
Drying
Greenhouses
Aguaculture
Hot water
Resorts and pools
Melting snow
8
Generation of Electricity is appropriate for sources >150oC
GEOTHERMAL’S POSITIVE ATTRIBUTES





Useful minerals, such as zinc and silica, can be extracted from
underground water.
Geothermal energy is “homegrown.” This will create jobs, a
better global trading position and less reliance on oil
producing countries.
US geothermal companies have signed $6 billion worth of
contracts to build plants in foreign countries in the past couple
of years.
In large plants the cost is 4-8 cents per kilowatt hour. This
cost is almost competitive with conventional energy sources.
Geothermal electric plants production in 13.380 g of Carbon
dioxide per kWh, whereas the CO2 emissions are 453 g/kWh
for natural gas, 906g g/kWh for oil and 1042 g/kWh for coal.
9
PROSPECT OF GEOTHERMAL ENERGY IN BANGLADESH!
10
Fig. Geothermal map of Bangladesh
(Guha et al., 2010)
Thank you
For
your kind attention!!