KEMBAR DAM N u s a T e n g g a r a B a r a t

I N V E N T O R Y S T U D Y O N D E V E L O P M E N T P O T E N T I A L F O R R U R A L E L E C T R I F I C A T I O N I N I N D O N E S I A KEMBAR DAM N u s a T e n g g a r a B a r a t Bandung, October 13, 2001

Inventory Study on Development Potential For Rural electrification in INDONESIA 1 S I T E R E P O R T MELIMBU MATARAM BATUCARAKEN PRAYA NUSA TENGGARA BARAT DESAANYAR KEMBAR DAM SELONG LABUAN HAJI N Kembar Dam - Suela 1. GENERAL INFORMATION Province : Nusa Tenggara Barat Regency : Lombok Timur District : Suela Village : Suela Site / Existing Dam : Kembar River : Lemor Gross Head : 6 m Estimate Design Discharge : 160 l/s Hydraulic Potential Power : 9.42 kw Estimate Electrical Power : 4.48 kw 2. SITE DESCRIPTION 2.1. Location Kembar (Dam) is one of the potential site for a Micro Hydropower (MHP) implementation. Kembar Dam existed in part of Tibu Jukung subvillage, Suela village, Suela district, Lombok Timur regency, Nusa Tenggara Barat province. It is 0 located geographically at S 08 30'56.5 and E 0 116 34'18.8. Suela village north border is Sapit village, Ketangga village at the southern side, Karang Baru village at the western side and Suntalangu village at the eastern side. such Kijang or motorcycle in about 40 minu - tes from Selong, or by a public transportation (buses, motorbikes) which services route among Selong - Suela - Tibu Jukung. (for more detail, see Table 1.). 2.3. Topographic and Geological Condition The MHP scheme will uses water from Lemor river. The river located on the east of Tibu Jukung sub-village. From the MHP scheme location (power house) the river goes Table 1. Route of Access Line Route Distance Duration Available Layer (road) Transportation Selong - Suela 25 km 30 minutes Buses Suela - MHP scheme location(tibu Jukung) 1.6 km 10 minutes Motorbike Asphalt Asphalt, Soil 2.2. Accessibility Tibu Jukung sub-village (Kembar Dam) located about 26.6 km to the northeast of Selong, Lombok Timur regency, Nusa Tenggara Barat Province. The location could be reach by four wheel vehicle to the south direction. Topographic conditions along the river (Kembar Dam) are moderate slope, while the materials around the river are loose soil and gravelly. Detail topographic map could be seen in Annex 3.

Inventory Study on Development Potential For Rural electrification in INDONESIA 2 S I T E R E P O R T 3. SOCIO - ECONOMIC CONDITION Village settlement in Tibu Jukung sub-village is quite concentrated. There is no adequate distance between every small group from one to another. Almost the villagers are farmers. Their main crops are paddy, and tobaccos. They still cultivate their land in traditional way, without any modern agriculture know-how. According to the agricultural potential in the area, Tibu Jukung are quite prospective to develop further. The only existing public facility is mosque, while several community organizations such as LKMD, farmer groups, religious groups, and village cooperative unit are existed in Tibu Jukung. Table 2. Sub-Villages which will electrified by The MHP Scheme Sub-Village Village Number of Latitude Line Longitude Line Household Tibu Jukung Suela 56 0 S 08 30'54.9 0 E 116 34'13.7 Total 56 4. POTENTIAL ENERGY SOURCES AND ELECTRIFICATION CONDITION The villages around the MHP scheme has not been electrified and will not get electricity from PLN or KLP (Local Electrification Group) grid, at least in the recent PLN (KLP) Plan. The nearest PLN electricity grid is about 0.2 km. Existing main energy sources for villagers there are kerosene, and oil for lighting. The village around MHP scheme location economically have many potential, especially in agriculture, and horticulture, sectors. However, related production facilities are still insufficient, there are some possibilities such as: storage facility, and rice mill. MHP development is expected giving valuable support to increase community economics quality apart from lighting need. As shown at Table 2, the number of households which will electrified by MHP scheme at Tibu Jukung sub-village are 56 households. Based on empiric data of electrification project using MHP, the estimate electricity need or electrical power need assumption is about 50 watt per house. Including the electricity need for several public facilities, then total MHP Capacity expected for Tibu Jukung villages is about 2.97 kw. Figure 1 Part of Kembar Dam at Suela village; Discharge measurement was arranged in this area.

Inventory Study on Development Potential For Rural electrification in INDONESIA 3 S I T E R E P O R T Table 3. Estimate Energy Demand in The Catchment Area Item Amount Capacity per Unit Capacity Remark Households 56 50 W 2.8 kw - Mosque 1 100 W 0.1 kw - Public Facility (Street Lighting) - 0.07 kw Total 2.97 kw 5. HYDRO-POWER POTENTIAL According to topographic measurement, water from Lemor River will be flowed directly into head tank (eliminating the headrace need). Detailed site plan could be seen at Annex 4. For this MHP scheme, measured gross head is about 6 m and estimated penstock length is about 34 m. Detail penstock profile is shown in Annex 5. Estimated minimum power electricity need in Tibu Jukung sub-village is about 2.97 kw. To fulfil this requirement, the MHP discharge have to be about 160 l/s with the estimate net head 5.5 m, with this calculation the MHP scheme could generate electricity power about 4.48 kw and still have reserved power about 1.51 kw (see detail calculation at Table 4.). Actual discharge measured of Lemor River is 166 litre/second. Recorded discharge data or annual discharge are not available and discharge measurement done not in the driest month, therefore maximum discharge in the dry season estimated about 160 l/s. However, design discharge has to be determined in detail and more accurate, considering all factor, and catchment area when a further feasibility study for this MHP done. 6. TRANSMISSION LINE Figure 2 Other side of Kembar Dam; The selected location for intake 1 The village settlement surrounding the MHP scheme are quiet concentrated and in small groups which have no significant distance from each other. Main transmission line to those sub-villages, as shown in Table 2, is about 610 m length. The transmission line design of Tibu Jukung sub-village is shown in Annex 6.

Inventory Study on Development Potential For Rural electrification in INDONESIA 4 S I T E R E P O R T I t e m Symbol Amount Estimate Gross Head Hg 6 m Measured Discharge ( when surveyed) Qm 166 l/s Design Discharge (max 60% from Q m) Qd 160 l/s Hydraulic Power Potential Ph 9.42 kw Estimate Net Head Hnet 55 m Estimate Turbine Efficiency Estimate Generator Efficiency Estimate mechanical transmission efficiency ht hg hm 0.7 0.85 0.97 Estimate Electrical Power Generated at the power house Pel1 4.98 kw Estimate transmission Losses Ploss 0.5 kw Estimate Electrical Power delivered to the village Pel2 4.48 kw Expected MHP Capacity (refers to table 3) Pexp 2.97 kw Reserved Power (P - P ) P 1.51 kw el2 exp Table 4. Estimate Power Capacity of The MHP Scheme res

I. DEMOGRAPHIC & SOCIAL Site / Dam River Village District Regency Province Distance to PLN Grid Number of Population Number of Households Means of Livelihood Economic Potential (Local Commodity) Kembar Lemor Suela Suela Lombok Timur Nusa Tenggara Barat 0.2 km 252 56 Farming Paddy, Tobaccos II. HYDRAULICAL CONDITION Gross Head Estimate Design Discharge Hydraulic Potential Power Estimate Electrical Power 6 m 160 l/s 9.42 kw 4.48 kw III. C I V I L Estimation of Weir & Intake of Weir Width (of Weir) of Intake Estimation of Headrace (Channel) Length Estimation of Head Tank (Forebay) Estimation of Penstock Length Diameter Estimation of Power House Permanent Stone Masonry 3 m Side Intake Stone Masonry - - - Existing Facility 34 m 38 cm Welded (Rolled) Steel Brick Masonry

IV. ELECTRO-MECHANICAL Estimation of Turbine Estimate Turbine Efficiency Estimation of Mechanical Transmission Estimate Mechanical Transmission Efficiency Estimation of Generator Estimate Generator Efficiency Estimation of Control System Ballast Load Crossflow 0.7 Flat Belt 0.97 Synchronous 0.85 Electronic Load Controller Air Heater V. TRANSMISSION LINE Estimation of Transmission Line Length 0.61 km

Photograph 1 Nature of Kembar dam building; The selected location for Power House of The MHP scheme. Photograph 2 The existing spillway facility; This could be harnessed further for the MHP scheme.