121-micro hydro powerplants ECs (electric cooperatives)Table Classification and applicability range of turbinesTurbine typeHEAD (Pressure)

High>40 m.Medium 20-40 m.Low 5-20 m.

ImpulsePelton

TurgoCrossflow(Banki)TurgoPeltonCrossflow(Banki)

ReactionFrancisPump-as-Turbine (PAT)KaplanPropellerPropellerKaplan

First Stage Project Planning Stagea. Selection of Potential Sitesb. Site Reconnaissancec. Planning of the Potential Sites d. Formulation of the Project Development PlanSecond Stage Project Implementation Stagea. Detailed Design and ConstructionFinal Stage Project Operation Stagea. Operation and Maintenanceb. Management Procedure

1.2 Components of Micro-Hydro Power-Diversion Weir and intake Diversion Weir a barrier built across the river used to divert water through an opening in the riverside into a settling basin-Settling BasinThe settling basin is used to trap sand or suspended silt from the water before entering the penstock. It may be built at the intake or at the forebay.-HeadraceChannel leading water to a forebay or turbine. The headrace follows the contour of the hillside so as to preserve the elevation of the diverted water.-HeadtankPond at the top of a penstock or pipeline; serves as final settling basin, provides submergence of penstock inlet and accommodation of trash rack and overflow/spillway arrangement.-PenstockA closed conduit or pressure pipe for supplying water under pressure to a turbine-Water Turbine and GeneratorA water turbine is a machine to directly convert the kinetic energy of the flowing water into a useful rotational energy while a generator is a device used to convert mechanical energy into an electrical energy.1.3 Concept of Hydro PowerA hydro scheme requires both water flow and drop in height to produce useful power.Losses: friction, heating, noise, etc.Power Conversion Equation is:Power input = power output + LossOr Power output = Power input x Conversion EfficiencyPower input, or total power absorbed is the gross power . The power output is the net power . The overall efficiency of the scheme is termed . in kWThe gross power is the product of the gross head , The design flow (Q) and a coefficient factor (g=9.8), so the fundamental hydropower equation is: in kW

Usually : 1.0 ((Channel length x 0.002 ~ 0.005)/ : 0.90 ~ 0.95 (depends on the penstock length) : 0.70 ~ 0.85 (depends on the type of turbine) : 0.80 ~ 0.95 (depends on the capacity of generator) : 0.97 : 0.90 ~ 0.98 (depends on the transmission length) : 0.98 and are usually computed as Head Loss (). In this case, the hydro power equation becomes: in kW2. Identification of potential sitesa. whether or not the construction of a plant near the power demand area is feasibleb. how much power capacity can be generated to sufficiently supply the demand areac. how to select a potential site among the candidate sites2.1 Basic Reference Materials1) Topographical map: scale: 1/50,000Topographical map provides important information such as landform, location of communities, slope of the river, catchment area of proposed sites, access road, etc. In the Philippines, topographical maps of scale 1/50,000 are available at the National Mapping & Resources Information Authority (NAMRIA).2) Rainfall data from Isohyetal and Regional Maps2.3) Calculation of River FlowQp = Rr X Qo/AoQp: River flow per unit catchment area in project area Rr: rainfall ratio between the rainfall at the proposed weir (or intake) siteRr: Rp/RoRp: Average rainfall at proposed weir site (mm)Ro: Average rainfall at gauged area (mm) Qo: observed river flow at existing gauging station (Ao: Catchment area of existing gauging station Ap: Catchment area of proposed weir site 2.4 Identification of Potential Sites2.4.1 Map StudyPotential sites are identified on the topographical map with a scale of 1/50000 by interpreting the head.The following parameters should be considered in the map study.(1) Site identification considering river gradient and catchment areaSites with high head, shortest waterway and a high discharge level are naturally advantageous for hydropower generation.(2) Identification based on the water conveyance route conditionsThe basic layout of a micro hydro development scheme is planned in such a way that its water conveyance facilities are exposed or surface-type structures.2.4.2 Identification Based on Local InformationIn some cases where potential sites cannot be identified or defined on the topographical map due to relatively small head or the absence of a cliff, a fall, or lake, pool, etc. As well as existing infrastructures like intake facilities for irrigation, roads, or trails, potential sites are identified on the basis of information gathered from a local source such as the local government units and/or local residents organization.2.4.3 Selection of Potential Development SitesThe potential sites are then examined for their suitability in hydropower development.(1) Level of firm dischargeWhile it is difficult to judge the suitability for development based on the absolute volume of discharge, a potential site with a relatively high level of firm discharge is a more favourable site for micro-hydro plant designed to supply power throughout the year.(2) L/H [ratio between waterway length (L) and total head (H)]A site with a smaller L/H value is more advantageous for small-scale hydropower.

Chapter 3 Site Reconnaissance3.1 Objective of Site ReconnaissanceThe objective of site reconnaissance is to investigate a single or several potential sites and the supply area or areas in order to evaluate the feasibility of projects and also to get information for electrification planning. One of the most important activities in site reconnaissance is to measure water discharge and head that could be utilized for micro-hydropower generation. Investigations of intake site, waterway route, powerhouse site and transmission line route etc. are also conducted to assess the feasibility of project sites.3.2 Preparation for Site ReconnaissanceTo achieve effective and fruitful site reconnaissance, it is important to be sufficiently prepared in the conduct of this part of the micro-hydro development study such as collecting of information on the target area and the preparation of work plan and schedule of survey activities in advance. 3.2.1 Information gathering and preparationAs advance information, 1/50000 topographic maps are prepared to check the topography of the target site and villages, the catchment area, villages household distribution and access road. More accurate information on site accessibility could be collected by contacting local people concerned.Copies of 1/50000 topographic maps and route maps enlarged by 200% and 400% are prepared for fieldwork.Check list and interview sheet are also prepared for each site reconnaissance.3.2.2 Planning of preliminary site reconnaissanceIt is important to make sufficient plan and schedule for site reconnaissance activities in advance. However, deviations from original plan and schedule in accordance with actual site conditions normally occur and should be expected. Before going to the site, proper coordination with local officials concerned should also be done to ensure the safety and successful conduct of the reconnaissance activities. Sufficient time to perform field activities should be planned since majority of potential micro-hydro sites are located in mountainous and isolated areas. The duration of site investigation, river flow (discharge) and head measurements, and other important activities for site reconnaissance should be properly estimated. A checklist or interview sheet should be prepared beforehand to conduct preliminary site reconnaissance activities.3.2.3 Necessary equipment for preliminary site reconnaissanceCheck Sheet of basic equipment for site reconnaissanceEquipmentEquipment

Map, SheetORoute map

EquipmentOAltimeter

OTopographic MapOGPS (portable type)

OReconnaissance ScheduleOCamera, Film

OCheck ListOCurrent meter

OInterview SheetODistance meter, measuring tape

Geological MapOHand level

Aerial PhotographOConvex scale (2-3m)

Related reportsHammer

Clinometer

StationaryOField notebookKnife

OScaleScoop

OPencilOTorch, Flashlight

OEraserSampling baggage

OColor pencilLabel

Section paperOCompass

Stop watch

Battery

3.3 Survey to Outline the Project SiteDuring the reconnaissance around the proposed site of micro-hydro power generating facilities and the power demand area, a survey is conducted on the following items:(1) AccessibilityConsiderations on planning for the transportation of equipment and access road other than the employment of simple machines/vehicles and the use of existing road, should be carefully done.(2) Situation of existing system and future planEven for a project site in which the development of a stand-alone type micro-hydro system is planned, survey should be conducted from the last or end of distribution line of an existing system or grid, its location, route and voltage, etc. and also on the possibility of extension or rehabilitation plans in case of an existing micro-hydro system.(3) Situation of river water utilizationAt the project identification stage, the situation or condition of the river for water utilization should be surveyed taking into account the possible recession section as well as the possibility of changes in the position of the intake or weir and the waterway route.(4) Existence of other development plans or projectsA survey should be conducted on the existence of other development plans/projects in terms of roads, agricultural lands, housing, tourism, etc. which may affect the planned project site and/or its surrounding area.(5) Civil structures in adjacent area and materials usedThe use of local labor and materials in the construction of civil structures are important in reducing the cost of a micro-hydro project thereby contributing to the local economy and ensuring maintenance and repair.(6) Presence of natural topographical features and existing structures usable for power generationWhen an existing irrigation channel or similar is used as a waterway for power station, it is necessary to check the cross-section, gradient and current water conveyance volume, etc. of such channel.(7) Existence of important ground features and vegetationFor this purpose the locations and conditions, etc. should be documented for discussions with concerned parties such as the landowner(s) and representatives of the local government.3.4 Investigation of Geological Conditions for Main Civil Structures(i) the exposed structure of most of the main civil structures(ii) the rooting of the waterway on a sloping hillside3.5 Survey on the Locations of Civil Structures1. Location of intake weir2. Headrace route3. Location of headtank or forebay4. Penstock route5. Powerhouse location6. Tailrace route7. Transmission line route3.6 Measurement of River Flow(1) Flow measurement method(2) Frequency of stream flow measurementStream flow measurement should be conducted at least three times a year to analyze the relationship between the water level and the discharge in the range below the observed maximum discharge level.(3) Water level observation unit3.7 Measurement of headThe head between the intake point and the headtank and the head between the headtank and the outlet point should be measured. At the initial planning stage, however, it may be sufficient to measure the head between the planned headtank location and the outlet level.3.8 Demand Survey3.8.1 Demand Survey MethodIt is necessary to estimate a slightly higher demand level than the assumed scale of power generation so that it would adequately respond to the scale of development as well as to the seasonal fluctuation of the power demand.3.8.2 Factors to consider in the demand survey(1) Location(2) Owners(3) Types and required quality of equipment(4) Equipment capacity, etc.(5) Period of use(6) Year of installation and service life(7) Likely problems associated with power cut3.9 Actual Field Survey(1) A proper understanding of the local topography is important for the planning of a small-scale hydropower plant like the main exposed structure civil structures. Topographical surveying is particularly required for such structures as the intake facility, headtank and generating station, etc., In general the accuracy of topographical surveying around civil structures tends to be in the range 1/100 1/200 for small to medium-scale hydropower plants. However, topographical surveying accuracy in the region of 1/500 should be sufficient for independent micro-hydro scheme because an error in topographical surveying hardly affects the work volume for small structures.(2) During the implementation stage: For the waterway and access road, etc., route surveying (center line and cross-section surveying) may be sufficient for planning and design purposes and should be effective from the viewpoint of cost reduction, particularly when the required surveying length is long. Those routes must, however, be carefully determined based on the results of the field reconnaissance conducted by the planner(s).Chapter 4 Planning4.1 Scheme of Development LayoutThe three options of water conveyance routes below are the possible layouts of micro-hydro power system.(1) Short PenstockThe penstock in this option is short but it requires a long headrace. A long headrace is subject to greater risk of landslides, erosion and siltation, or deterioration. The construction of the headrace along a steep slope is difficult and expensive. Also the risk of erosion in case of a steep slope makes this scheme unacceptable and not practical since it will make the future operation and maintenance difficult and expensive.(2) Long Penstock The penstock route layout generally follows the river because it may not be possible to construct a headrace along the surrounding terrain. One of the most important considerations in this scheme is to ensure that seasonal flooding of the river will not damage or cause deterioration to the penstock. In this scheme the cost will be particularly high since this will require more penstock pipes which are more expensive than a headrace channel.(3) Mid-length PenstockThis scheme involves a medium length penstock and a relatively medium length headrace channel. While the penstock in this scheme may cost more than the short penstock, the cost of constructing a headrace along a steep slope may be avoided. The initial purchase and construction costs for this scheme are greater than the short penstock scheme; however, this option may be preferable in case there are signs of instability in the steep slope.4.2 Data Gathering for Planning 4.2.1 Hydrograph and Flow Duration Curve Hydrograph shows how flow varies throughout the year and how many months in a year that a certain flow is exceeded. The flow duration curve simply takes all the flow records over many years and placing them with the highest figures on the left and the lower figure placed progressively over to the right.4.2.2 Plant Factor and Load Factor(1) Plant FactorPlant Factor is very important in micro-hydro power planning. Plant factor is defined in the equation:

And

Where;: the possible annual electric generation (kWh)Pmax: maximum output (kW)Qave: average discharge which is less than Qd Qd: design discharge For a run-of-river type micro-hydropower scheme, optimum plant factor can be generally taken from the following range:For micro-hydro: 80~100%Small-hydro: 45~65%(2) Load factor

4.3 Selection of Locations for Main Civil Structures4.3.1 Location of Intake(1) River Channel Alignment(2) Stability of Hillside Slope(3) Use of existing civil structures(4) Use of natural topographical features(5) Intake Volume and Flood Water Level(6) Site Conditions for Settling Basin and Headrace, etc.(7) Present River Water Use(8) Existing Features that maybe Affected by the Backwater4.3.2 Headrace Route(1) Topography(2) Ground Stability of Headrace Route(3) Use of Existing Structures4.3.3 Location of Head Tank(1) Topographical and geological conditions(2) Ease of Dealing with Effluents4.3.4 Penstock Route(1) Hydraulic Gradient(2) Topography of the Penstock route(3) Ground Stability of the Penstock Route(4) Use of existing infrastructures like roads, irrigation canals and others4.3.5 Location of Powerhouse (1) Accessibility(2) Conditions of foundations(3) Flood water level(4) Installation Conditions for Auxiliary Facilities4.3.6 Location of Tailrace (1) Flood water level(2) Existence of Riverbed Fluctuation at Tailrace(3) Possibility of Scouring(4) Flow Direction of River Water4.4 Supply and Demand Plan4.4.1 Selection of Power Demand FacilitiesThe following items must be considered to determine the installed capacity.(1) Power Uses1) Use for Lighting2) Use for Electric Heating 3) Use for Motive Power (2) Transmission and Distribution Cost(3) Contribution to Local Developmenta) Those capable of using local resourcesb) Those capable of appealing the local characteristics to outside the areac) Those capable of assisting the creation of employment opportunitiesd) Those capable of contributing to the promotion of exchanges between local residents.4.4.2 Examination of development scale and supply and demand balanceIt is necessary for the output of a micro-hydro power plant which has no back-up power generation source to always exceed the demand. In the case of a run-of-river type micro-hydro power plant, the optimal scale is that which corresponds to the maximum demand capacity within the range of the developable maximum output which is basically determined based on the minimum usable discharge for generation. The procedure for this examination is discussed in the following topics.(1) Decision on Minimum Usable Discharge for GenerationThe minimum usable discharge for generation is decided in consideration of the ff. Items:a) Establishment of usable river discharge for generation Which is calculated by subtracting the maintain discharge in the reduced discharge section from the river discharge at the intake point.b) Frequency of permissible break power generationIt is decided by the type and importance of the power demand facilities/equipment, user intentions and other factors.(2) Decision on Maximum Output a) Case of constant demand throughout the yearb) Case of seasonal demand fluctuation (3) Decision on Scale of Development and Power Demand Facilitya) Case where change of demand plan is difficultb) Case where change of demand is possiblea. Setting up of demandb. Calculation of effective use of electrical energy 4.4.3 Daily Supply and Demand PlanChapter 5 Design for Civil Structures5.1 Intake Weir5.1.1 Types of Intake WeirsThe basic types of intake weirs are:(1) Concrete gravity(2) Floating Concrete(3) Earth Dam(4) Rockfill Dam(5) Wet masonry weir(6) Gabion weir(7) Concrete reinforced gabion weir(8) Brushwood weir(9) Wooden weir(10) Wooden frame with gravel weir5.1.2 Weir Height Calculation(1) Conditions restricting waterway elevationIt is necessary to examine the topographical and geological conditions of the identified weir construction site and also along the identified weir construction site and also along the identified water conveyance routes or alignments. It is advisable that further evaluation should be conducted in case the cost of weir construction accounts for a large portion of the total project construction cost.In case the intake weir is planned along a river that is adjacent to a road, the elevation of the road should be taken into account in establishing the height of the weir to protect the road from flooding.(2) Possibility of riverbed rise in downstream 1) Gently sloping river with a high level of transported sediment.2) Existence of a check dam, etc. in the downstream of the planned weir site that is not yet filled with sediments.3) Presence of landslide or eroded portion and the possibility of continuous erosion downstream of the proposed intake weir site.4) Existence of a narrow section in the downstream which obstructs the flow of sediment and any debris carried by the flow.(3) Conditions to remove sediment from upstream of the weir and settling basin by intake method (tyrolean-type intake and side intake)(4) Influence on construction cost and electrical energy generated(5) Influence of back water5.2 Intake5.2.1 Intake Design1) Bar-screen type2) Bar-less type5.2.2 Important points for Intake DesignIn micro-hydro power development, the type of headrace adopted is usually an open channel, a covered channel, or a closed conduit. When any of these types of headrace is employed, it is important to avoid large volume of water inflow that exceeds the designed intake capacity as it will directly affect or damage the headrace.In planning for the intake facility of a micro-hydro power plant, it would be advantageous to consider the omission of the intake gate to reduce the project cost. However, if an intake gate is required for safety and practical reasons, it is recommended that a manually-controlled gate should be used instead of an automatic controlled gate to avoid increase in cost.In the case of an intake facility for a micro-hydro power plant located in a remote and mountainous area, a swift response to flooding is difficult. 5.4 Headrace5.4.1 Type and Basic Structure of HeadraceThe headrace channels for small-scale hydropower plants are generally designed to convey a small amount of water only. These structures are basically exposed or constructed at ground level such as an open channel or a covered channel, etc. Some examples of headrace and their basic structures are given in Table 5.4.1 and Table 5.4.2 respectively.Chapter 6 Design for mechanical and electrical structures6.1 Fundamental equipment and facilities of micro-hydro power plantThe fundamental equipment and facilities discussed in the preceding chapters are tackled in more detailed manner in this chapter. In addition, a summary of recommended micro-hydropower generating equipment for rural electrification is presented herein for quick reference.

Note: Basic conditions for micro-hydropower turbines for rural electrification in the Philippines1) Stable for long term operation2) Easy operation by semi-skilled operator(s) or villager(s)3) Locally fabricated turbines for easier maintenance and repair (except small parts)4) Cheaper cost of equipment including installation5) Acceptable technical guarantees of the turbine.Equipment and FacilityPurpose and Function1. Inlet valveTo control the stop or supply of water to turbine from penstock.2. Water turbineto change the energy of water to the rotating power3. Governor of turbineto control the speed and output of turbine4. Power transmission facilityto transmit the rotation power of turbine to generator5. Generatorto generate the electricity from turbine or its transmitter6. Control and protection panelto control and protect the above facilities for safe operation7. Switchgear (with transformer)to control on/off operation of electric power and step-up the voltage of transmission lines

6.2Turbine6.2.1 Type and output of water turbine The types of water turbine are mainly-classified into two types:1) Impulse turbine: Pelton turbine, Crossflow turbine, Turgo-impulse turbine2) Reaction turbine: Francis turbine, Propeller turbine: Kaplan turbine, Diagonal mixed flow, tubular turbine, and straight flow turbineNote:1) Impulse turbine: turbine types that rotate the runner by the impulse of water jet having the velocity head which has been converted from the pressure head at the time of jetting from the nozzle.2) Reaction turbine: Turbine construction that rotates the runner by the pressure head of flow.Shaft arrangement: The arrangement of turbines will be also classified into two types, Horizontal shaft (H-Shaft) and Vertical Shaft (V-shaft)Referring to the required output, available net head and water flow (discharge), the following types of turbine may be applicable for micro or small hydraulic power plant of rural electrification.(1) Horizontal Pelton turbine(2) Horizontal Francis turbine(3) Crossflow turbine(4) Tubular turbine (S-type tubular turbine, Vertical tubular turbine, Runner rotor integrated turbine, vertical propeller turbine, Horizontal propeller turbine)(5) Turgo impulse turbine(6) Reverse pump turbine (Vertical propeller turbine, Horizontal propeller type, Submerged pump type)6.2.3 Design of Crossflow turbineCrossflow turbine (T-13 and T-14)1. Get the basic data for rated water flow (, elevations (m) of water level at forebay and turbine center (or tailrace water if designed as special case) from civil design.2. Calculate the net head from gross head by deducting head loss of penstock3. Estimate the net hydraulic power and turbine shaft output from water flow, net head and turbine efficiency.4. Calculate width of turbine runner according to manufacturers recommendation.5. Calculate the mechanical power to generator from efficiency of power transmitter6. Calculate rated electrical output of generator (kW) Maximum output of electricity7. Calculate the rotational speed of turbine from specific speed, turbine shaft output and net head.8. Select suitable generator available at the market and its output (kVA), frequency, voltage power factor and rotational speed, referring to catalogue of generator manufacturer.9. Calculate the ratio of rated rotational speed of turbine and generator.10. Select the width and length of belt referring to belt manufacturers recommendation.11. Calculate the capacity of dummy load and suitable ELC (Electronic Load Controller) or IGC (Induction Generator Control) in case of induction generator.12. Calculate the diameters of the pulley for the turbine and generator.Note:Basic data of T-13 and 14 available from the model test.Diameter of turbine: 300mmNo. of runner blade: 28Unit speed: 133rpm6.2.4 Design of reverse pump type turbine (pump as turbine)A water pump used as turbine by reversing rotation of pump is called the Pump as turbine (PAT)1. To calculate and get the effective head, water flow, and net hydraulin power as same method as item 1, 2, and 3 of above2. To check suitable pump available in the market, considering maximum efficiency point of pump, rotation speed of motor because the direct coupling between turbine and generator is usually adopted for this kind of turbine.3. To select and finalize the pump as turbine, considering the maximum efficiency point of pump, applicable efficiency for actual output of turbine shaft because of the range of high. Efficiency point is very narrow.4. The selection method shall be referred to the Design Manual for Reverse Pump Turbine.6.3 Generator6.3.1 Type of Generator1. Fundamental classification of AC generator(1) Synchronous generator: Independent exciter of rotor is provided of each unit. Applicable for both independent and existing power network (2) Induction generator: No exciter of rotor is provided Usually applicable for network with other power source. Sometimes applicable for independent network with additional capacitors for less than 25kW but notso recommendable for independent network due to difficulty of voltage control and life time of capacitors except cost savingShaft arrangement: Either vertical shaft or horizontal shaft is applied to both type of above generators.2. Another classification is also applied to AC generators as follows;1) Three phase generator: Star () connection for 3 phase 4 wire networkDelta () connection for single phase 2 wire netwok2) Single phase generator: This type is not used in power network system because it is difficult to purchase the generator with capacity of more than 2kW in the market. In this case three phase generator with delta connection is applied as shown above.6.4 Power Transmission Facility (Speed Increaser)There are 2 ways of coupling the turbine and generator.1) Direct coupling of the turbine shaft and the generator shaft.2) Indirect coupling that uses power transmission facility between turbine shaft and generator shaft.Two types of speed increaser are as follows:1. Gear box type: Turbine shaft and generator shaft is coupled with parallel shaft helical gears in one box with anti-friction bearing according to the ratio of speed between turbine and generator. The lifetime is long but the cost is relatively high. (Efficiency: 95-97% subject to the type)2. Belt type: Turbine shaft and generator shaft is coupled with pulleys (flywheels) and belt according to the ratio of speed between turbine and generator. The cost is relatively low but lifetime is short. (Efficiency: 95-98% subject to the type of belt)The belt type (V-belt or flat belt) speed increaser is usually adopted for micro-hydro power plants because it is very much lower in cost compared to the gear type transmitter.6.5 Control Facility of turbine and generator6.5.1 Speed GovernorIt is adopted to keep the turbine speed constant. The speed of the turbine fluctuates if there are changes in the load and water flow. The governing or control of turbine speed is necessary for the proper operation of the hydropower facility.The governing device is classified into speed detector, controller and operation. There are two types of governor to control water flow through turbine by operation of guide vane or by balancing the load by interchanging the demand load and the dummy load, as follows:1. Mechanical Type: to constantly control water discharge with the automatic operation of guide vane(s) or valves according to actual load.a) Pressure oil operating type guide vane(s) or gate valve(s)b) Motor-operated type guide vane(s) or gate valve(s)2. Dummy load type: To control the balancing of both current load and dummy loaf thyristor i.e. to keep the summation of both actual and dummy load constant for the same output and speed of generator.Speed detection is made by PG (pulse generator), PMG (permanent magnet generator) or generator frequency.In case of the mechanical type, ancillary equipment such as servomotor of guide vane, pressure pump, pressure tank, sump tank, piping etc. or electric motor operating guide vane with control system, are required. This means the cost of the hydropower plant will be higher with such additional equipment.In case of motor operating type, power source, motor and operating mechanism are also required. For a micro-hydropower plant, the dummy load type governor is less expensive and recommended.6.6 Control, Instrumentation and Protection of Plant6.6.1 Control Methods of PlantThere are many control methods for hydropower plant, such as supervisory control, operation control, and output control1. Supervisory control method is classified into continuous supervisory, remote continuous control and occasional control.2. Operational control method is classified into manual control, one-man control and full automatic control.3. Output control method is classified into output by single governor for independent network and water level control, discharge control and program control for parallel operation with other power source.6.6.2 Instrumentation of Plant1. Pressure gage for penstock 2. Voltmeter with change-over switch for output voltage3. Voltmeter with change-over switch for output of dummy load (ballast)4. Ammeter with change-over switch for ampere of generator output5. Frequency meter for rotational speed of generator.6. Hour meter for operation time7. KWH meter and KVH meter, which is recommended in order to check and summarize total energy produced by the power plant if there is some allowance in budget.6.6.3 Protection of Plant and 460/230V distribution lineConsidering the same reason for cost is saving in instrumentation, the following protection is required as minimum protection for micro-hydro power plant in rural electrification1. Over speed of turbine and generator2. Under voltage3. Over voltage4. Over current by NFB (No fuse breaker) or MCCB (Molded case circuit breaker) for low tension circuit6.6.4 Protection of 13.2 kV Distribution lineNormal protection system of line (Pole-mounted type lighting arresters and fuses or fuse switches) is to be provided throughout the line.1. The following facilities are to be installed at 13.2 kV switchgear of power station for large capacity and long outgoing line is required.1) 1 no.18 kV circuit breaker, driven by AC operated closing and tripping system of capacitor trip power supply device (3-phase 200A for MHP)2) 3 nos.18 kV fuse switches with fuse, hand operated type (3-phase)3) 1 no.18 kV earthing switch, hand operated type (3-phase gang operated)4) 3 nos.13.2 kV lightning arrester5) 1 no.13.2 kV voltage transformer (3 phase, 18kV/110V)6) 3 nos. 13.2 kV current transformer (1-phase, ratio to be fixed by the actual capacity of micro-hydro power plant)7) 1 set18 kV busbars system8) 1 no.Control and protection panel2. The following facilities only are to be installed by connection from 13.2 kV terminal of 13.2 kV/460V transformer on the terminal pole at power plant, in case only 13.2 kV/460V transformer is installed for set-up purpose due to small capacity distribution line. 1) 3 nos.18 kV fuse switches with fuse, hand operated type (3-phase)2) 3 nos.13.2 kV lightning arrester (more than 27kV, 5kA)3) 1 lot13.2 kV line connection materials (insulators, support structure, wires)6.7 Inlet ValveReferring of water quantity and head of plant, suitable inlet valve is applied between penstock and turbine for tight stopping of water supply for safety and maintenance. However, it may sometimes be omitted for purpose of cost saving in case of low head power plant if the stop log or gate at forebay can almost stop the water leakage from forebay into penstock or separate discharge pass-way is provided at forebay. The inlet valve for micro and small power plant is classified into three kinds as follows:Chapter 7 Design for distribution facilities7.6 Conductors and cables7.6.1 Advantages/DisadvantagesThe feature of conductor and cable is shown at ff table:AdvantagesDisadvantages

Conductors-cheap-easy to connect each conductor-not safe

Cables-safe-could be laid underground-expensive-difficult to connect each cable

7.6.2 Sizes of ConductorsSized of conductors should be selected taking into account the amount of present load, forecasted load, short-circuit current, current capacity of conductors, voltage drop, power loss, mechanical strength, etc. too many sizes shall not be used for branch feeders.7.6.3 Allowable sag of conductorsThe sag of conductors should be determined with respect to the allowable conductor tension, strength of the supporting structures, wind load on conductors, etc. the conductor should be maintained above the ground at a height shown in table below:Conductor height above ground13.2 kVLow Voltage

Road crossing6.5 m4.0 m

Along road6.0 m4.0 m

Other places6.0 m4.0 m

7.6.4 Allowable load per phase3-phase distribution lines are needed to keep the load balanced. If the unbalance load is more than 20%, appliances and instruments are subjected to harmonic distortion.7.6.5 Application 3-phase line The 3-phase distribution line should be extended up to the load center or villages. This is to minimize current that causes system losses along the lines. If this could not be done due to high cost, it is necessary to conduct close monitoring of the connected load in each phase and keep the load balance or nearly balance.7.7 Distribution TransformersIn case of 13.2 kV distribution line is used instead of 460/230V line due to long distance from power station to consumers with the reason of sending capacity, voltage drop etc., some step-up and step-down is completely similar. Step-up transformer is installed at power station side for step-up from 460/230V to 20/11.5kV and step-down transformer is installed at consumers area for step-down and vice versa.7.7.1 Type of Distribution TransformerDistribution transformers are classified into the type of insulation, as follows:Oil immersed transformer: Windings are immersed in insulation oil in tank and cheaper.Dry type transformer: Windings insulated with heat-resisting epoxy (H-Class) without tank but expensive.Distribution transformers are classified into two kinds by winding method as followsThree-phase transformer: - connection Suitable for grounding of neutral point- connection- connectionNote: ; Delta connection; Star connectionSingle phase transformer: Usually used for voltage step-down from 13.2/8kV to 230V near consumers area.Single phase transformer can also be used both star and delta connection by outside connection with combination of 3 transformers.7.7.3 Application of Distribution TransformersStep-up and step-down distribution transformers shall be of three-phase construction and their standard capacities are as follows:5 kVA, 10 kVA, 16 kVA, 25 kVA, and 50 kVA7.7.4 Selection of Unit CapacityTable 7.7.1 Relation between capacity of transformer and generatorCapacity of transformer5 kVA10 kVA16 kVA25 kVA50 kVA

Capacity of generator-4 kW4 kW 8 kW8 kW 12.8 kW12.8 kW 20 kW20 kW 40 kW

Before deciding the unit capacity of new transformers, the supply area of new transformers is to be determined taking into account the followings:(a) Supply area of new transformers shall not overlap with that of other transformers supplied from other feeders.(b) Supply area of each transformer must be independent.(c) Voltage drop restriction should be satisfied at any part of the supply area.7.7.5 Location Step-up transformers shall be located near the powerhouse. Step-down transformers shall be located in or close to the load center of the area. In deciding the final location to install transformer, the following conditions should also be examined:(a) Easy to access and replacement works.(b) To be separated from other buildings or trees with enough clearance.(c) For pole mounted type, pole assembly shall not be complicate.7.8 House Connection (HC)7.8.1 Application of House ConnectionFor HC, copper core or aluminum core twisted cable will be used.The sizes of the copper core are: The sizes of the aluminum core are: Chapter 8 Project Cost Estimate8.1 Rough Cost Estimate During Planning StageDescriptionItem

PlanMaximum Output (kW)

Turbine Discharge

Effective Head (m)

Intake FacilitiesHeight of Dam (m)

Length of Dam (m)

HeadraceLength of Headrace (m)

PenstockDiameter of Penstock (m)

DistributionNumber of Households (HH)

Distance from powerhouse to the farthest house (km)

8.2 Cost Estimation for Detailed Design Stage8.2.1 ItemsTypical items of a direct cost are shown below.(1) Preparatory Works- Location Setting Out- Filling and Measurement- Equipment and Materials Mobilization(2) Civil Works- Intake Facilities- Settling Basin- Headrace- Head tank- Spillway- Penstock and Foundation- Powerhouse base- Tailrace- Power house building- Finishing(3) Electro-Mechanical Works- Turbine- Controller- Dummy Load- Generator- Accessories, Spare parts and Tools- Set up and Installation- Transportation and Packing- Testing- Pre commissioning Trial Run(4) Distribution Works- Transmission Pole- Cable- Transformer- Accessories(5) Consumer Connection- Cable- Switch- AccessoriesTable 8.2.1 Construction CostNo.ItemCost

Direct cost of construction

1PREPARATORY WORKSAddition item

2CIVIL WORKSAddition item

3ELECTRO-MECHANICAL WORKSAddition item

4DISTRIBUTION WORKSAddition item

5CONSUMER CONNECTIONAddition item

SUB TOTAL (A)

Indirect cost

1DESIGN FEE5 ~ 10% of SUB TOTAL (A)

2SUPERVISOR FEE5 ~ 10% of SUB TOTAL (A)

3MANAGEMENT FEE5 ~ 10% of SUB TOTAL (A)

4TAX12.5% of SUB TOTAL (A)

SUB TOTAL (B)

TOTAL

Table 8.2.2 Quantity of DamGabion DamMasonry DamConcrete Dam

Excavation Backfill Gabion Excavation Backfill Foundation Rubble Stone Stone Masonry Plaster Stoplog Gabion Excavation Backfill Sand filling Concrete Plaster Stoplog Gabion

Table 8.2.3 Quantity of HeadraceSimple Earth ChannelMasonry ChannelConcrete Channel

Excavation Excavation Backfill Foundation Rubble Stone Stone Masonry Plaster Excavation Backfill Sand filling Concrete Plaster

8.2.3 Unit CostTable 8.2.4 is the standard unit cost per work item of civil work of a project in a certain area.

Table 8.2.4 Unit Cost per work itemWork ItemCoefficientUnitUnit PriceUnit Cost

EXCAVATION

Unskilled labourForemanTools0.6250.0621.0man-dayman-day1s

Total

BACKFILL

Unskilled labourForemanTools0.1920.0190.010man-dayman-dayman-day

Total

SANDFILLING

Unskilled labourForemanTools1.2000.150man-day

Total

FOUNDATION RUBBLE STONE

StoneSandUnskilled labourSkilled labourForeman1.2000.4001.1250.5630.056

man-dayman-dayman-day

Total

STONE MASONRY 1:2

StonePortland CementSandUnskilled labourSkilled labourMasonForeman1.2003.5200.3802.2501.1250.1130.017bags

man-dayman-dayman-dayman-day

Total

STONE MASONRY 1:3

StonePortland CementSandUnskilled labourSkilled labourMasonForeman1.2002.8400.4002.2501.1250.1130.017bags

man-dayman-dayman-dayman-day

Total

Work ItemCoefficientUnitUnit PriceUnit Cost

STONE MASONRY 1:4

StonePortland CementSandUnskilled labourSkilled labourMasonForeman1.2002.5000.4202.2501.1250.1130.017bags

man-dayman-dayman-dayman-day

PLASTERING

Portland CementSandUnskilled labourSkilled labourMasonForeman0.2370.0190.2860.2140.0210.021bags

man-dayman-dayman-dayman-day

Total

GABION

StoneWire CageUnskilled labourSkilled labourForeman1.2003.5000.4500.2000.020kgsman-dayman-dayman-day

Total

STOPLOGS (set)

WoodCarpenterLabourForemanTools0.0481.0002.0000.1001.000man-dayman-dayman-day1s

Total

WORK AREA FLOOR

Portland CemenrSand for concreteSplit GravelToolsUnskilled labourSkilled labourMasonForeman3.9560.5500.9301.0002.0000.5000.0500.010bags

1sman-dayman-dayman-dayman-day

Total

REINFORCED CONCRETE

Portland CementSplit GravelToolsUnskilled labourSkilled labourMasonForemanToolsSteel bar for concreteWireLabour steelmanForeman steelmanUnskilled labourCommon nailCarpenterCarpenter foreman7.8960.8100.4903.0000.5000.0500.1101.000175.02.0006.7502.2508.7504.0005.0000.500bags

man-dayman-dayman-dayman-day1skgskgsman-dayman-dayman-daykgsman-dayman-day

Total

Chapter 9 9.1 Construction Management for Civil Facilities9.1.1 PurposeConstruction management is performed by the contractor to satisfy the standards and to complete the construction works economically and safely within the construction period. Construction management includes progress control, dimension control, and quality control.9.1.2. Progress ControlProgress control is the management of construction process for assuring the execution of work efficiently and economically within construction period by effectively, utilizing the machines, labour and materials while maintaining sufficient quality and accuracy instead of merely controlling a series of processes for observing the completion date. (1) Procedure of progress controlProgress control is made for each of the planning, implementation, reviewing and handling steps.(2) Construction schedule chartVarious time schedules should be graphically prepared for progress control and then used as standards for implementation, review and handling. The following forms are normally used for control chart.(a) Horizontal line type schedule charts (Gantt chart, bar chart)(b) Curve type schedule charts (graph type)(c) Network type schedule charts (PERT, CPM)9.1.3 Dimension Control(1) Direct measurementFor knowing the shape (dimensions, quantity, reference height, etc.) of an object created by the works, the shape is directly measured in accordance with the sequence of construction works and the measured values are then compared to design values.(2) Photographic recordsPhotographic records are made as supplementary data for later confirmation of the progress of the works including conditions before and after the works, the portions, that may not be seen upon completion of the structure, and the results of direct measurements.9.1.4 Quality Control(1) Procedure of quality control(a) Standards for materials(b) Quality standards(c) Work Standards(d) Test and Inspection Methods(2) Quality characteristicsTable 9.1.1 Examples of quality characteristicsKindQuality characteristicsTests

ConcreteSlumpAir ContentCompressive strengthBending StrengthSlump testAir content testCompression testBending test

EarthGrain sizeDegree of compactnessPenetration indexIn-situ CBR valueGrain size analysisDry density testVarious penetration testsIn-situ CBR test

AsphaltDensity and voidsTemperature at delivery to siteFlatness of pavement surfaceMarshall testTemperature test at deliver to siteFlatness test

(3) Control method(a) Histogram(b) Control Chart9.2 Construction Management for Turbine, Generator and Their Associated Equipment9.2.1 Installation(1) Heavy machinery(2) Manpower of direct labourers and technicians(3) Temporary facilitiesa) Distribution board for temporary facilities should be consideredb) Lodging facilitiesc) Warehoused) Site construction office(4) General tools and consumables(5) Classification of installation worka) Inspection of dimensions and level of concrete foundationb) Transport of materials, parts and equipment from warehouse to power stationc) Unpackingd) Preparing scaffoldse) Assembly and installationf) Welding and gas cuttingg) Wiringh) Piping work and flushingi) Hydraulic pressure testj) Non-destructive testk) Centering, levellingl) Shaft runout testm) Painting(6) Inspection during installationa) Centering & levellingb) Shaft runout measurementc) Measurement of caps of rotating parts d) Confirmation of dimensions of each portione) Dye Penetration Test or ultrasonic crack examination for field welds of stress carrying partsf) Relation between guide vane opening and servomotor strokeg) Insulation resistance measurement9.2.2 Adjustment during test run operation(1) Instruments, tools and materials(2) Manpower ScheduleTest PeriodThis varies depending on the types of turbine and generator, equipment configuration, experience of testers but is normally 1 to 2 months(3) Test itemsa) Appearance inspectionb) Insulation resistance measurementc) Withstand voltage testd) Tests for turbine ancillary equipment- Performance test for governor- Tests for oil pressure supply and lubricating systems- Tests for water supply and drainage systemse) Exciter combination testsf) No-water overall testsg) Water filling testsh) Initial running testsi) Automatic start and stop testsj) Synchronizing testsk) Load rejection testsl) Output and opening testsm) Vibration measurementn) Load testsChapter 10 Operation and Maintenance10.1 Introduction(1) Operators must efficiently conduct operation and maintenance of the micro-hydropower plant with strict compliance with the O and M rules and regulations.(2) Operators must familiarize themselves with all the plant components and their respective performance or functions. Furthermore, they should also be familiar to measures against various accidents for prompt recovery.(3) Operators must always check conditions of facilities and equipment. When they find some troubles or accidents, they must inform the person in charge and try to recover it.(4) Operators must try to prevent any accidents. For the purpose, they should repair or improve facilities preventively as necessary.10.2 OperationThe operation of micro-hydropower plants is not only to generate electric power but also to control generation equipment and to supply electricity of stable quantity and quality to consumers and maintaining all facilities in good condition.10.2.1 Basic Operation (1)Check points before starting operationBefore starting operation of the power plant, operators must check the following facilities are in good condition for operation. Especially in the case of after long term operation, they should be checked thoroughly.1)Transmission and distribution line Damages of lines and poles Approaching branches Other obstacles2)Waterway facilities Damages of structures Sand sedimentation in front of the intake Suspended trash at screens Sand sedimentation in the settling basin and the forebay3)Turbine, generator and controller Visual inspection Wear of brush Insulation resistance of circuits(2)Starting OperationAfter checking the turbine and generator are okay for operation. Procedure of starting operation is as follows:(Preparation)1) Close the flushing gate of the intake weir2) Open the intake gate and intake water into the waterway system.(Starting operation)3) Open the inlet valve gradually.4) If there is a guide vane, open the inlet valve fully, and then open the guide vane gradually.5) Confirm that voltage and frequency or rotating speed increase up to the regulated value.6) Turn the load switch on (parallel in)7) Control the valve or guide vane so that voltage and frequency are within the regulated range.(3)Role of operators during operationOperators must control the equipment in order to supply electricity of good quality keeping equipment normal and safe as follows:1) Control the inlet valve or guide vane so that voltage and frequency are within the regulated range.2) Check vibration and noise of equipment, and then stop operation if necessary.3) Check temperature of equipment.4) Check any abnormal condition of equipment, and then stop operation and take a measure if necessary.5) Record result of operation and condition of equipment according to fixed format.(4)Stopping operationIn order to avoid longer runaway speed of the turbine and the generator, the procedure stopping operation is as follows:1) Close the inlet valve or the guide vane.2) Cut load switch off (load rejection)3) Close the inlet valve and the guide vane completely.4) Close the intake gate.10.2.2 In case of emergency(1)In case of floodIn general micro hydropower plants can be operated even in the case of flood, however, when the river becomes muddy and if there is possibility that sand and soil will enter into the facilities, operation of the plant should be stopped by closing the intake gate. After flood, operators must inspect all facilities first prior to resumption of operation.(2)In case of earthquakeSince an earthquake affects all facilities of plants, operators must inspect facilities after a big earthquake as follows: Check damage of structures Misalignment of the shaft of the turbine and the generator Damages of other electrical equipment Others(3) In case of shortage of water There is an applicable range of water discharge for each turbine. Therefore, a turbine should be operated within the range.Micro hydropower plant should basically be designed along water discharge in the dry season. However, in case of shortage of water that is beyond of our expectations, operators must stop operation because continuous operation under such condition will damage the turbine.(4)In case of accidentIn case of accident, operators must stop operation, investigate the cause and try to recover operation as soon as possible. Operators roles are as follows:1) Immediately inform the accident to the person in charge.2) Investigate accident in detail.3) Look into the causes of accident.4) Recover operation as soon as possible if operators can prove the causes and repair by themselves.5) Contact makers or suppliers of equipment and request them to repair if the operators cannot find the causes and cannot repair themselves.What operators should prepare in advance are as follows: Discuss with maker or supplier of equipment on possible measures in case of equipment trouble. Present to the Barangay Alternative Power Association (BAPA) management about expenditure on the recovery.6) Inform the DOE and LGU regarding the accident.

10.2.3 Others(1)Filling water in waterway systemsProcedure of filling water into the waterway system is as follows:1) Confirm all flushing gates and valve of the water system was open.2) Open the intake gate partially, and intake small volume of water.3) Close the flushing gate of the settling basin after cleaning the headrace and the forebay.4) Close the flushing gate of the forebay after cleaning the headrace and the forebay.5) Close the drain valve of the penstock after cleaning the penstock.6) Fill the penstock with water gradually.7) Open the intake gate fully after filling up the penstock.(2)Flushing sand in front of intakeIf sand sedimentation reaches the intake level, sand will be carried into the water way system and it will affect the penstock and turbine blades. Therefore, in order to prepare against outflow of sand and soil during flooding, operators must keep the intake approach open. For the purpose, operators should sometimes flush or remove sand that settled in front of intake.If flushing gate is installed at the intake weir, operators can flush sand out by water flow opening the gate during flooding. However, incase of having no flushing gate, operators must remove sand out of the weir manually.(3)Control of intake waterVolume of intake water changes according to water level of river. Normally excess water should be spilled out at spillway, which is located at settling basin or headrace. If the excess water reaches the spillway of the forebay for long time, it may possibly wash out the structure due to lack of spillway capacity. Therefore, operators must control the intake gate so as to avoid too much water spill.10.3 MaintenanceIn order to operate micro hydropower plants in good condition for long period, waterway facilities, electric equipment, and transmission and distribution line should be maintained adequately. Operators must try to observe even a small trouble and prevent accident of facilities. For the purpose, daily patrol and periodic inspection are essential and recording and keeping of those data are also important. Though items and frequency of patrol and inspection should be decided considering condition of facilities and ways of use, general maintenance of micro hydropower plants is as follows:

10.3.1 Daily patrolIn order to check if there is anything strange at waterway facilities, electric equipment, transmission and distribution line, operators must record result of patrol and take a measure if necessary.

10.3.2 Periodic InspectionOperators must conduct inspection periodically to check if there are any troubles in facilities and equipment. Operators, preferably, should be able to perform repair works in case there are troubles during inspection, if necessary.

10.3.3 Special InspectionIn case of earthquake, flood, heavy rain and accident, operators must stop operation and inspect facilities.

10.4 RecordingOperators must keep a record of the operation and maintenance of the micro-hydropower plant. Records will provide much help to operators in monitoring the conduct of the regular or scheduled activities for the operation and maintenance. It also provides good data in determining the causes of trouble in case of accident.

Chapter 11 Management

11.1 Establishment of Organization

Micro-hydropower projects for rural electrification are different from private power companies, in which all parties concerned that include the consumers, O&M groups, community organizations, and Barangay, Local and Central governments, have to accomplish their roles and responsibilities to ensure sustainable operation.

An O&M organization called the Barangay Alternative Power Association (BAPA) should be established to take care of the operation and management prior to project implementation. The BAOA should have its by-laws and elected officials duly recognized by a General Assembly.

11.2 Management System

Background

More than a half of existing micro hydropower plants in rural areas is non-operational due to various causes of troubles. Most operators do not have appropriate knowledge and skill on operation and maintenance for micro hydro plants. Usually, budget for operation and maintenance were not given due importance. As a result, operators cannot work well for the plant without sufficient salary. Also, they cannot implement preventive maintenance for the equipment without enough money. This will usually result to curative maintenance which is more expensive or if not implemented will result to operational stoppage. Therefore, the causes of problems of micro hydropower plant are not only due to low quality of facilities and equipment but also insufficient management practice of concerned organization.

In order to manage the BAPA, rules and regulation that provide objectives, members role and responsibilities, scope of work, etc. should be established before commissioning the plant. It should also be necessary to stipulate respective responsibilities in the by-laws of the association, all pertinent rules and regulation that shall be binding and imposed up to the operational life of the power system. Importantly, training on management should also be conducted.

11.3 Reporting and Monitoring

Operational data and maintenance results should be recorded and kept because it will be used as basis of operators to find out the causes of trouble in the future. Likewise, record of tariff collection and balance sheet of income and expenditure are essential for BAPA to manage itself substantially.

11.4 Decision-Making System

The General Assembly is the final approval of all decision made which are not stipulated in the By-Laws of the organization. The proposal should be approved by the Board of Directors (BOD) before it will be presented to the General Assembly.

11.5 Accounting System

Formulate and implement rules and regulations of the organization Collect electrify tariff from consumers, and manage income and expenditure Operate and maintain power supply electricity to consumers efficiently and safely. Repair or replace facilities and equipment is necessary. Instruct consumers on guideline of safe and efficient usage of electricity. Report result of operation and maintenance of the plant and financial management of DOE and related LGU periodically.11.6.1 BAPA Officials1)Chair Person:Chair person is the Head of the BAPA Organization. His duties are: Comprehensive