GEOTHERMAL RESOURCE EXPLORATION AND DEVELOPMENT IN ETHIOPIA. Short course III Exploration of Geothermal Resource Naivasha, Kenya November 2008

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1 THE FEDERAL DEMOCRATIC REPUBLIC OF ETHIOPIA MINISTRY OF MINES AND ENERGY Geological Survey Of Ethiopia GEOTHERMAL RESOURCE EXPLORATION AND DEVELOPMENT IN ETHIOPIA Short course III Exploration of Geothermal Resource Naivasha, Kenya November 2008

2 ETHIOPIA LAND AREA = 1.1 M SQ.KM POPULATION ~ 75 MILLION Has Largest portion of the GREAS (1000 Km) ( E.G.P: > 5000 MWe)

3 ENERGY RESOURCES IN THE COUNTRY HYDRO GEOTHERMAL NATURAL U GAS BIOMASS COAL WIND SOLAR

4 Energy supply TIC= 783 MWe Hydro= 671 MWe Thermal= 112 Mwe Geothermal= 7.33 MWe 22% of the Population have access to E PLANNED TO REACH TO 50 % BY 2015 ETHIOPIAN ELCTRIC POWER SUPPLY Others- traditional Biomass

5 STATUS OF GEOTHERMAL ENERGY RESOURCE EXPLORATION AND DEVELOPMENT IN ETHIOPIA

6 The First Geothermal License in Ethiopia April 22, 1903

7 Exploration began in 1969 (UNDP & EG) About 18 Geothermal Prospect areas were identified in the whole ERV (covers 13% of the country) Much larger are for direct uses (agriculture, agroindustry etc) LARGEST GEOTHERMAL RESOURCE IN AFRICA

8 FILWIHA SODERE WONDO GENET

9 GEOTHERMAL PROSPECTS OF ETHIOPIA Geothermal Area Detail Survey Drilling Max. Temp o C 1Abaya Yes No 2 Corbetti Yes 94 3 Aluto Langano Yes Yes 350 4Tulu Moye Yes No Gedemsa No No Kone No No 7Fantale Yes No 8Dofan Yes No 9 Meteka No No 10 Danab No No 11 Teo No No 12 Abe No No 13 Tendaho Yes Yes Note: + Geothermometer value 16 sites known

10 ALUTO-LANGANO TENDAHO TENDAHO ONLY TWO AREAS ARE SUBJECTED TO DRILLNG ALUTO-LANGANO (LD- AREA) KM S. OF A.A A TENDAHO (N.AFAR)- 650 KM NE OF A.A ALUTO-LANGAO

11 THE ALUTO-LANGANO GEOTHERMAL FIELD

12 L a k e Ziw a y ( LA-2 LA-7 LA-8 LA-6 LA-3 LA-4 LA-5 Geological Mapping 1:50, scale RHYOLITE LA Km LITHOLOGICAL AND STRUCTURAL STUDIES Lake Langano Simplified Geological Map RHYOLITE HEAT SOURCE Abundant silicic volcanoes, recent volcanic products (2000Yrs.) PERMEABILITY BASALT WFB and other transverse faults (production of secondary Permeability) SiO 2 Total Alkali-Silica diagram for classification of Aluto outcropping rocks.

13 Bobesa SURACE ALTERATION MINERAL STUDIES Bole

14 FLUID CHEMISTRY SAMPLING POINTS Springs, BH, TG-Wells, Lakes etc..

15 Water Classification Bole SP Cl Shalla NE SP Shalla SW SP-2 Chitu Sp TG-31 TG Wondo (Belle) Wondo (Giorgis) A BICARBONATE 25 SO HCO Figure 12A. Cl - HCO3 -SO4 PLOT (2003)

16 Evaluation of Na-K-Mg temperatures Q Bole Sp SP-84 SP-2 TG-32 TG Na/ Shalla (SW) Chitu HS Wondo (Giorgis) Wondo (Belle) Na-K geothermometer= C immature waters K/ Figure 13A. Evaluation of Na-K-Mg temperatures ( ). After Giggenbach (1988) Sqrt Mg

17 GEOPHYSICS ELECTRICAL RESISTIVITY MAGNETICS GRAVITY TG WELLS WERE DRILLED

18 USE of ER as a tool for siting drilling locations was constrained by the rock succession : Due to its inability to attain sufficient depth pentration below a conductive layer of AVP & LS A combination of topographic and geological structure complexity the volcanic edifice itself didn t allow the emergence of a clear electrical resistivity structure ALUTO-VOLCANIC PRODUCTS Lake sediments Basalt Tertiary ignimbrite It is recommended to complement this survey with an MT survey to provide a delineation of the target area and to have a better resolution in the vertical dimension

19 THE ALUTO-LANGANO GEOTHERMAL FIELD DETAIL EXPLORATION INCLUDING DRILLING TOOK PLACE IN LA-3 FINANCIALLY SUPPORTED BY EEC, UNDP AND THE ETHIOPIAN GOVERNMENT

20 HYDROTHERMAL ALTERATION MINERALS Propylitic Cavity filling

21 CLAY MINERAL STUDIES Mixed Layer Illite smectite Illite-chlorite Chlorite intergrade illite chlorite Chlorite intergrade

22 FLUID INCLUSION GEOTHERMOMETRY CHAIXMECA H-F STAGE

23 TYPES OF INCLUSIONS P-INCLUSIONE Qz V-RICH INC S-INCLUSIONE Cc Qz

24 Results of Fluid inclusion studies M.T

25 NONE OF THE FLUID FROM THE WELLS REPRESENT THE PARENT FLUID

26 GEOCHEMISTRY Water and gas sampling from thermal manifestations Analyse for major cations and anions Data processing using various geochemical softwares (e.g. WATCH, SOLMINEQ 88 etc..) AAS GC Determine the reservoir temperature using various chemical geothermomters (e.g. Si-geothermometer, Na-k, Na-K-Ca geothermometers)

27 Cl LA-6 ( ) LA-3 ( ) CHEMICAL GEOTHERMOMTER ~ C GAS GEOTHERMOMETER ~ SO FIGURE 2: A plot of Cl-HCO3-SO4. HCO3

28 SATURATION INDICES S I ) ( x d e n I n o a t i u r S a t Quartz Amorphous silica Saturatio on Index (SI) Calcite Quartz Amorphous silica Calcite Temperature ( C) FIGURE 6: A plot of SI vs temperature (well LA-3) Temperature ( C) FIGURE 8: A plot of SI vs temperature (well LA-4)

29 Lake Ziway 2000 DOWNHOLE TEMPERATURE PROFILES Figure 1: Downhole Temperature Profiles (Aluto wells) ( LA-2 LA-8 LA-7 3 LA-6 LA-3 LA-4 LA (m.a.s.l) Elevation( LA Km Lake Langano Legend Temperature ( C) LA1-T16 LA2-T13 LA3-T55 LA4-T33 LA5-T18 LA6-T15 LA7-T27 LA8-T10 File:Tempelveation

30 One of the Discharging Wells At Aluto, LA-6 FIVE WELLS ARE POTENTIALLY PRODUCTIVE WITH A MAX. TEMPERATURE OF 350 C. FEASIBILITY STUDY WAS COMPLETED IN 1986 BY GSE AND ELC, ITALY THAT INDICATED 30MWe OF GEOTHERMAL POTENTIAL TO LAST FOR 30 YEARS. IN 1995, THE FIELD HANDED OVER TO EEPCO FOR DEVELOPMENT

31 TERTIARY IGNIMBRITE TERTIARY IGNIMBRITE CONCEPTUAL MODEL OF THE A-L GEOTHERMAL SYSTEM

32 THE ALUTO-LANGANO GEOTHERMAL PILOT POWER PLANT 3MWe

33 CURRENT ACTIVITY PROBLEM IDENTIFICATION REHABILITATION OF THE PLANT

34 THE WAY FORWARD FOR ALUTO Further MT + TEM studies for location of wells for further appraisal drilling Drilling of Appraisal and production wells Resource Development in various phases

35 TENDAHO GEOTHERMAL FIELD

36 TENDAHO GEOTHERMAL FIELD T.G.F AFAR TRIPLE JUNCTION

37 TENDAHO GEOTHERMAL FIELD Ayrobera Doubti Allalobeda

38 Afar Stratoid Series TENDAHO GEOTHERMAL AREA

39 TENDAHO GEOTHERMAL FIELD EXPLORATION HISTORY RECONAAISSANCE SURVEY (1969/70) PRE-FEASIBILITY STUDY (1979/1980) TECHNO ECONOMIC STUDY (1982) DRILLING OF 3 DEEP & A SHALLOW WELLS ( ) 2 SHALLOW WELLS DRILLING ( ) 1998) WELL TESTING & GEOSCIENTIFIC STUDIES (1998- TO DATE) FINANCED BY ITALIAN AND ETHIOPIAN GOVT.

40 15-3 My 1.4 Ma GEOLOGICAL MAP OF THE TENDAHO GEOTHERMAL AREA (Aquater, 1996)

41 Surface alteration along manifestations Surface alteration along manifestations

42 TENDAHO TD-3 TD-4 TD-1 TD-2 3 DEEP (2100 m) & 3 SHALLOW WELLS (500m) WERE DRILLED MAXIMUM TEMP = 260ºC AT A DEPTH OF 500M TD-5 TD-6 LOCATION OF WELLS IN THE LOCATION OF WELLS IN THE TENDAHO GEOTHERMAL FIELD

43 AN OVERVIEW OF TENDAHO GEOTHERMAL WELLS Well No. TD1 TD2 TD3 TD4 TD5 TD6 Drilled depth (m) Permeable zone *cased & sealed Tmax ( o C) * Status t of the Non- Productive Non- Productive Productive Productive well productiv productive e Chemical composition of deep waters (mg/l) SiO HCO TDS PH Gas composition of wells (vol%) H 2 S CO

44 SUMMARY OF EXPLORATION RESULTS EXISTNANCE OF SHALLOW RESERVOIR ( C) PROVEN POTENTIAL OF SHALLOW RESERVOIR ESTIMATED AT 3-5MWe DEEP RESERVOIR INDICATED (>270 C) LOCATION OF DEEP DRILL WELL SITES TO BE IDENTIFIED

45 MT INVESTIGATION AT TENDAHO (DUBTI &AYROBERA)

46 Sediments/Volcanics Hot geothermal fluid AFSS CONCEPTUAL MODEL OF THE TENDAHO (Doubti) GEOTHERMAL FIELD

47 The way forward for the Tendaho Geothermal Field Location and delineation of the deep reservoir Identification of Shallow reservoir volume Characterize the shallow reservoir by installing a small scale pilot power plant Further drilling to reach to the deep reservoir & develop the field

48 PROSPECTS S AT ADVANCED EXPLORATION STAGE FINANCED BY ETHIOPIAN GOVERNMENT AND THE WORLD BANK

49 DOFAN-FANTALE TULU MOYE TULU MOYE CORBETTI ABAYA

50 GEOTHERMAL PROSPECT AREAS FROM SOUTH TO NORTH OF THE LD PROSPECT 1: ABAYA PROSPECT 2 : CORBETTI PROJECT 3: TULU MOYE PROSPECT 4: DOFAN FANTALE

51 ABAYA GEOTHERMAL PROSPECT AREA 400 KM SOUTH OF A.A DETAILED GEOSCIENTIFIC STUDIES INCLUDING MT SURVEY HAVE IDENTIFIED A TEMPERATURE IN EXCESS OF 260 C. FURTHER GEOPHYSICAL SURVEY (MT+TEM) ARE RECOMMENDED. 132 KV TL WITHIN 45 KM OF THE PROSPECT AREA

52 CORBETTI About 250 Km S of AA Detailed Geoscientific including 8 TG wells CTG-1 CTG-2 CTG-3 CTG-4 Max. M Temp = 250 ºC CTG-8 CTG-5 CTG-7 C Drilling D is justified to define the extension of reservoir Geological Map of Corbetti Geothermal Prospect Area. Surface and near surface exploration are recommended before drilling 132 KV TL passes within 15 Km of the Prospect

53 TULU MOYE GEOTHERMAL PROSPECT AREA DETAILED GEOSCIENTIFIC STUDIES INCLUDING 5 TG WELLS HIGH TEMP > 200 ºC & GOOD PERMEABILITY TARGET AREAS FOR DEEP WELLS ARE SELECTED Lateral extent/depth of geothermal reservoir unknown TG-1 LOCATED CLOSE TO AWASH I AND II POWER STATIONS

54 THE DOFAN & FANTALE GEOTHERMAL PROSPECT AREA LOCATED ABOUT 250 KM NE OF AA DETAIL GEOSCIENTIFIC STUDIES ARE COMPLETED IN SEVERAL HYDROTHERMAL MANIFESTATIONS WITHIN THE VICINITY LATERAL EXTENT/DEPTH OF GEOTHERMAL RESERVOIR UNKNOWN

55 I B Geological and Structural Maps of the Dofan Fantale Geothermal Prospect Area R

56 Surface Alteration Studies

57 FLUID CHEMISTRY 0 Cl 100 Legend Filoa-2 H.Sp Filoa-3 H.Sp Habilo H.Sp Hubicha-1 H.Sp Hubicha-2 H.Sp Melka T. H.Sp Merti Bh Metehara Bh Debhiti Bh Awash Rv Bulga Rv Kebena Rv Arowadi Dw Beseka Lk 100 SO HCO3

58 25 0 Na/ Legend Filoa-2 H.Sp Filoa-3 H.Sp Habilo H.Sp Hubicha-1 H.Sp Habilo (Sp-4) Hubicha-2 H.Sp Melka T. H.Sp immature waters K/ Sqrt Mg

59 δ 2 H Legend Hot springs Boreholes Rivers Dug well Lake (GMW WL) δ 2 H = 8δδ 18 O+10 evaporation evaporation 10 0 SMOW Habilo 18 O - Shift = δ 18 O

60 GEOPHYSICAL INVESTIGATION RESIDUAL GRAVITY MAP APPARENT RESISTIVITY MAP

61 Schematic Conceptual Model of the D-F G.P.A

62 CURRENT ACTIVITY RESERVOIR ENGINEERING & GEOSCIENTIFIC STUDIES OF THE TENDAHO GEOTHERMAL FIELD INTERPRETATION OF MT &TEM DATA DETAILED GEOSCIENTIFIC STUDIES (Geology &Geochemistry) OF THE ABAYA GEOTHERMAL PROSPECT AREA PROBLEM IDENTIFICATION AND REHABILITATION OF THE ALUTO- LANGANOGEOTHERMAL PILOT POWER PLANT

63 DURING THE THREE DECADES THAT GEOTHERMAL RESOURCE EXPLORATION WAS CARRIED OUT GOOD INFORMATION BASE GOOD DEGREE OF EXPLORATION AND HUMAN CAPACITY BASIC INSTITUTIONAL AND INFRASTRUCTURE HAVE DEVELOPED. HOSTED 1 ST ARGEO CONFERENCE IN ADDIS ABABA, ETHIOPIA NOVEMBER 2006

64 THE WAY FORWARD IN PROSPECTIVE AREAS Advancing as many prospect areas as possible to Exploration drilling Selection of two geothermal potential areas for exploration drilling Selection for Det.Exp. ll be based on the geothermal Potential and proximity to existing national electrical grid Execute power Development activities such as: () (i)resource Development (ii) Drilling for steam field development (iii)power plant installation

65 POSSIBLE STRATEGIES FOR FURTHER EXPLORATION AND DEVELOPMENT IN ETHIOPIA

66 Currently the desire to Increase the geothermal development and utilisation in Ethiopia inspired by: Critical role of energy in socio-economic devt of the country Energy demand growth Rural Electrification focus Increasing world oil price Frequent q drought and shift to Generation Mix Clean Development Mechanism availability Growth of interest of private investment (Japan, Iceland) Availability of required inputs (Human Resource, Rigs etc..) for GED Existence of identified potential geothermal prospect p areas

67 POSSIBLE STRATEGY FOR GEOTHERMAL EXPLORATION AND DEVELOPMENT IN ETHIOPIA 2 2. TENDAHO Corbett Abay 6. D-FANTALE 5.T.MOYE 1. ALUTO 3. CORBETTI 4. ABAYA

68 THE WAY FORWARD GOVT. OF ETHIOPIA IS COMMITTED TO DIVERSIFY AER. (ROAD MAP) Hold an Investment/Donor Conference Dec PROSPECT 1: ALUTO LANGANO PROSPECT 2: TENDAHO PROSPECT 3 : CORBETTI PROSPECT 4: ABAYA PROJECT 5: TULU MOYE PROSPECT 6: DOFAN FANTALE GEOTHERMAL STRATEGY TO FURTHER EXPLORE AND DEVELOP ABOUT 500 MWE FOR THE COMING YEARS.

69 CONSTRAINTS AND OPTIONS FOR DEVELOPMENT CONSTRAINTS AND OPTIONS FOR DEVELOPMENT OF GEOTHERMAL RESOURCE IN ETHIOPIA

70 CONSTRAINTS AND OPTIONS FOR DEVELOPMENT OF GEOTHERMAL ENERGY No. Constraints t Options 1. Geothermal not in National Integrate Geothermal in Energy Development Plans National Energy Development Plans 2. Large upfront cost of Promote PPP, IPP Exploration and Development Participation of Finance, bilateral donors and development agencies (e.g. UNDP, WB) Use the Opportunity of RMF/TAF (ARGeo) 3. Limited budget for full fledged exploration Establish Policy to provide enough budget 4. Lack of continous and integrated work kin exploration Establish a process/system for uninterrupted and development of the Geothermal exploration and resource development activity

71 SUMMARY Geothermal is known to be a reliable, indigenous, environmental friendly & cost effective alternative energy resource. A substantial Potential of G. E. Resource exist within the Ethiopian Rift System that can be used for power generation and direct uses. Government is Committed to Investigate and Further Develop Geothermal Resource to Supplement and Diversify Energy Consumption Dueto: - Strong Growth in Electrcity Demand - Recurrent Drought - Increase of Petroleum Prices Long term conducive policies and incentives that attract private investment is already established in the country Encourage foreign technical and financial participation Establish a sound CB Mechanism for sustainable GED Establish a process/system for an integrated geothermal exploration and development of the resource with aview to quick development and implementation possible.

72 THANK YOU