1. Hakim SAIBI & SAEED September 2014
Geothermal Energy
Winner of GRC 2011 photo contest, Reykjanes Geothermal Power Plant, Iceland
Hakim SAIBI & SAEED
September 2014

2. Few Keywords Feasibility studies Two phase flow IEA Brine Energy Well
Renewable Energy
Thermal plants
Hybrid systems
Efficiency
Exergy
Reservoir
Geofluid
Two phase flow
Brine
Well
Drilling
Enthalpy
Entropy
Surface facilities
Utilization
Scaling
Corrosion

3. Geothermal Reservoir Fed by Rain Water
"Geothermal" comes from the Greek words geo (earth) and therme (heat). Thus, geothermal means earth heat. Geothermics can be defined as the study of the temperature distribution in the earth and the phenomena that influence that distribution.
The Earth’s heat is continuously radiated from within, and each year rainfall and snowmelt supply new water to geothermal reservoirs. Production from individual geothermal fields can be sustained for decades and perhaps centuries, which explains the renewability of this resource (Geothermal Education Office 2001).

4. Clay Diablo Fumarole (CA)
Hot Springs
Geysers
Clay Diablo Fumarole (CA)
White Island Fumarole
New Zealand
Fumaroles

5. Earth Temperature Gradient

6. Geothermal Regions in the World
Geothermal systems are located in regions with a normal or slightly above normal geothermal gradient, creating low-to-medium enthalpy geothermal reservoirs (less than 150°C). The high enthalpy geothermal reservoirs (up to or above 400°C) are especially located in regions around plate margins with high geothermal gradients. The circulation of water in terrestrial geothermal systems can reach depths of approximately 5 km (Pirajno 1992).

7. Geothermal Electricity in the World
Geothermal energy is the most versatile renewable energy and has been used for thousands of years for washing, bathing, cooking and health: the direct utilization of the hot water is long lasting and still growing with different application ranges. The world’s first geothermal district heating system was started in the 14th century at Chaudes-Aigues, France, and the first geothermal well was drilled near Reykjavik, Iceland, in However, only in the 20th century has geothermal energy been harnessed on a large scale for space heating, electricity production, and industrial use. The first large municipal district heating service was initiated in Iceland in the 1930s and currently provides geothermal heat to approximately 99% of the 200,000 residents of Reykjavik. The first commercial plant to produce electricity became available in 1913 in Larderello, Italy. The use of geothermal energy has increased rapidly since the 1970s. During the period , the globally installed direct use capacity tripled from 15 to 50 GWth, whereas the installed capacity for electricity production increased from 8.0 to 10.7 GWe. At present, geothermal energy is used by 78 countries for heating purposes (called ‘direct-use’) and by 24 countries for electricity production. Figure 1 shows the use of geothermal electricity throughout the world (Bertani 2012).

8. Historical Trend of Geothermal Installed Capacity
The increase in the installed capacity over the last century is clearly visible in Figure 2, with an impressive increase in new plants started in the 1980s, following the energy crisis.

9. Direct Uses of Geothermal Energy

10. Geothermal Reservoir Modeling Workflow

11. Numerical model of synthetic enhanced geothermal system with isosurfaces of temperature after 30 years of heat mining by injection of cold water from the central well and production from two peripheral wells that intersect the stimulated fracture zone.

12. Japanese Geothermal Power Plants
(GRSJ, 2011)

13. Geothermal Energy in Japan

14. How you can get involved?!
Educational
Professional

15. Topics Borehole geology and alteration mineralogy
Chemistry of thermal fluid
Drilling (depth of interest!)
Energy policy (local and global scale)
Environmental aspects
Geological explorations
Geophysics
Geothermal energy utilization
Geothermal reservoir
Geothermal resources assessment
Hydrology and hydrogeology
Logging
Well testing
Extensive field works

16. Education
UNU-GTP (United Nations University-Geothermal Training Program, Iceland)
Geothermal diploma course, University of Auckland, New Zealand
Smaller contributions from Universities in Japan, USA, Italy, Mexico.

17. Classification of Geothermal Resources
Temperature (ºC)

18. Japanese Geothermal Resources Classification
Enthalpy-Entropy diagram for Water and Steam

19. Geothermal Utilization
High temperature
Low temperature

20. Geothermal Resources Hot dry rock
- no water at all, still no commercial utilization
Vapor dominated fields
- deliver steam ready for the turbine
Water dominated fields
- water flows into the wells, and boils partly
Liquid water
- temperature below 100°C (The fluid contains non-condensable gases and dissolved solids)

21. The cycles Flash (Bjarnarflag (backpressure), Nesjavellir)
Double flash (Krafla, Svartsengi)
ORC (Svartsengi)
Kalina (Husavik)

22. Direct use applications
District heating and snow melting
Spas and swimming pools
Greenhouses
Fish farming (aquaculture)
Drying

25. Before and after geothermal space heating
REYKJAVÍK
Before and after geothermal space heating
1930
1990
District heating in Reykjavík started in By 1970 nearly all Houses in Reykjavík were receiving hot water for heating and sales began to nearby municipalities. Today Reykjavík Energy serves about people or 99.9% of the population of Reykjavík and five neighboring communities.

27. ENVIRONMENTAL IMPACT OF GEOTHERMAL UTILIZATION

28. Environmental Concerns
Surface disturbances
Physical effects - fluid withdrawal
Noise
Thermal pollution
Chemical pollution
Protection
Social and economic effects

29. Surface Disturbances Excavation Construction Roads Landslides Scenery
Changes in surface activity
Untidiness

30. Mitigation Drillrigs disappear after Small area of activity, Use
Abandoned or unused
boreholes can be hidden
Small area of activity,
mostly underground
Source usually exploited
near drillsite

31. Sustainable Development
Sustainable development: Development that meets the needs of the present without compromising the ability of future generations to meet their own needs (World Commission on Environment and Development 1987)

32. Sustainable Production of Energy from an Individual Geothermal System
For each geothermal system, and for each mode of production, there exists a certain level of maximum energy production, E0, below which it will be possible to maintain constant energy production for a very long time ( years). If the production rate is greater than E0 it cannot be maintained for this length of time. Geothermal energy production below or equal to E0 is termed sustainable production, while production greater than E0 is termed excessive production (Axelsson et al. 2001)

33. Geothermal sustainability

34. Cascade Utilization of Geothermal Energy

35. ?

36. Winter is coming, stay together!