Micro-Hydro. Module Introduction. Tokyo Electric Power Co. (TEPCO)

Transcription

1 Module 4.1 Micro-Hydro Introduction Tokyo Electric Power Co. (TEPCO) Workshop on Renewable Energies November 14-25, 2005 Nadi, Republic of the Fiji Islands Subjects to be Covered in Workshop Potential Site Site Identification Preliminary Site Site Survey Planning Designing Implementation Operation and and Maintenance 2

2 Contents to be Covered in Introduction Hydropower Concept of Hydropower Theoretical Hydropower Output from Hydropower Equipment Efficiency Energy Generation Types of Hydropower Plant Micro-Hydropower Characteristics of Micro-Hydro Components of Micro-Hydro Plant Project Cost of Micro-Hydro Plant Development Flow Pre-Implementation Stage Implementation Stage Operation & Maintenance Stage 3 Hydropower

3 Concept of Hydropower Potential Energy (Mass of water located at a higher elevation) Kinetic Energy (Water flows as a result of the mass being at a higher elevation.) Mechanical Energy (Flowing mass of water turns a turbine runner.) Head (m) Electric Power in Kilowatts (kw) (Turbine runner turns a directly coupled generator.) 5 Theoretical Water Power Theoretical Hydropower Output : Work volume per 1 second (J/s) when the water of Q (m 3 /s) drops from the height of H(m) P 0 = ρ g Q H (J/s = W) = 9.8 QH (kw) Where, P 0 = Theoretical hydro power output (kw) ρ = Water density: 1000 (kg/m 3 ) g = gravitational acceleration: 9.8 (m/s 2 ) Q = Discharge per unit time(m 3 /s) H = net head (m) 6

4 Practical Hydropower Practical Hydropower Output P = P 0 η tg = 9.8 Q H η tg (kw) Where, P = Power output η tg = Combined efficiency of generating equipment = Turbine efficiency (η t ) Generator efficiency (η g ) Output kw kw kw kw kw ,000 kw Efficiency of Japanese generating equipment Turbine η t Generator η g Efficiency (%) Combined η tg Experience in Developing Countries (Efficiency) Expected Output: 25 kw (η tg 0.6) Actual Output: 15 kw (η tg 0.36) Result Insufficient electricity supply Cause Equipment efficiency is lower than expected one since the equipment was manufactured by a local metal worker 8

5 Energy Generation Energy Generation = P T (kwh) Where, P: Power Output [kw] T: Time [hours] If electricity is continuously generated for one year at the output of 1 kw, Annual Energy Generation= 1 kw 24 h/day 365 days = 8,760 kwh 9 Exercise 1 Q1: Net head: 40 m, Design discharge: 1 m 3 /s Q1-1: How much is the theoretical hydropower (kw)? Q1-2: In the case that the combined efficiency is 0.75, How much is the hydropower output? Q1-3: How much can be generated annually (kwh)? Suppose the availability rate is 50% Q2: In the case that the actual max. output is 150 kw, How much is the combined efficiency (η tg )? 10

6 Exercise 1 (Answer) Q1: Net head: 40 m, Design discharge: 1 m 3 /s Q1-1: How much is the theoretical hydropower (kw)? P 0 = 9.8 Q H = = 392 (kw) Q1-2: In the case that the combined efficiency is 0.75, How much is the hydropower output? P= P 0 η tg = = 294 (kw) Q1-3: How much can be generated annually (kwh)? Annual generation = P T 0.5 = = 1,287,720 (kwh) 11 Exercise 1 Q2: In the case that the actual output is 150 kw, How much is the combined efficiency (η tg )? η tg = P / P 0 = 150 / 392 = % 12

7 Types of Hydropower Plant Classification by Water Usage Run-of-River Type Pondage Type Reservoir Type Pumped Storage Type Classification by Method of Head Acquisition Waterway Type Dam Type Dam and Waterway Type 13 Run-of of-river Type (by water usage) Uses water within the range of the natural river flow. Has no reservoir or pondage to regulate the river flow. 14

8 Pondage & Reservoir Type (by water usage) Pondage type Has a pond that enables regulating the river flow for one to several days. Supplies power in response to the demand. Reservoir type Has a reservoir that enables regulating the river flow seasonally or annually. Supplies power in response to the demand. 15 Pumped Storage type (by water usage) Has an upper pond (reservoir) and a lower pond (reservoir). Generates power during peak demand. Pumps up water during low demand. Upper Reservoir : Peak Demand : Low Demand Power House Lower Reservoir 16

9 Water Way Type (by Method of Head Acquisition) Head is created by the difference in elevation between a steep river gradient and a gentle slope waterway. No high dam, only a diversion weir Flow cannot be regulated and output fluctuates according to the natural river flow. Pipeline or Canal Intake Weir Weir Settling Basin Settling Basin Settling Channel Headrace Tunnel Settling Channel Forebay Settling Channel Powerhouse Penstock Tailrace River Forebay Headrace Tunnel Penstock Powerhouse Tailrace Settling Channel Turbine/ Generator 17 Dam Type (by Method of Head Acquisition) Head is acquired mainly by the height of the dam. Enables regulation of the power output in response to load fluctuation. Reservoir or Pond Dam Penstock Intake Powerhouse Tailrace Reservoir or Pond Dam Tailrace Powerhouse Intake Penstock 18

10 Dam & Water Way Type (by Method of Head Acquisition) Combination of the waterway type and dam type to create head reservoir or pond Intake dam Head tank Penstock reservoir or pond Intake dam Pressure tunnel river Pressure tunnel Head tank Powerhouse Tailrace Tailrace Powerhouse Penstock 19 Micro-Hydropower

11 What s s Micro-Hydro Hydro? 100 kw (300 kw) or below Mainly run-of-river type and waterway type Stable generation source for the rural electrification Supply to; - Just rural industry or a factory for self-use - One or several isolated rural communities - Mini-grid in rural area Generation technology with a history and a simple principle that can be managed by local people Minimal environmental impact High initial costs, but no fossil fuel required for its operation Provides electricity for lighting, livelihood activities and other multipurpose development Power can be supplied for 24 hours a day 21 Components of a Micro-Hydro Power Plant Headrace (Pipeline and/or Canal) Weir and Intake Spillway Forebay Penstock Electrical Lines Powerhouse Tailrace Turbine/ Generator River 22

12 Weir & Intake (Components of Micro-Hydro) Weir: Obstruction in the river to raise the water level to divert water to the headrace Require neither a high dam nor a big reservoir Intake: Structure to take water from the river 23 Settling Basin (Components of Micro-Hydro) A pond to collect and flush out sediments like sand and soil To prevent for suspended materials to enter the waterway Sometimes omitted in cases that inflowing sand and soil is minimal 24

13 Headrace (Components of Micro-Hydro) Conveys water from the intake to the forebay Usually an open canal made of concrete, but sometimes it is made of soil and/or pipes 25 Forebay (Components of Micro-Hydro) A pond-like structure at the top of the penstock to take water in the penstock from waterway A spillway is connected to a forebay. Functions as a final settling basin for suspended materials in water 26

14 Penstock (Components of Micro-Hydro) Pipe to convey water from forebay to turbine Steel pipe in case of high pressure Hard vinyl chloride plastic pipes or FRP(Fiver Reinforced Plastic) pipes in case of low pressure 27 Power house (Components of Micro-Hydro) A house for electro-mechanical equipment (turbine, generator, controllers and panels) Sufficient space for dismantling equipment during repair and maintenance activities 28

15 Turbine & Generator (Components of Micro-Hydro) Turbine: Converts the water energy to rotational power Generator: Generates electricity from the rotational power of the turbine 29 Special Application of Micro-Hydro Application to the Sewage Treatment Plant (1) No of Turbine Max. Output Effective head Max. discharge Generator type Intake method 1 (M model) 37 [kw] 5.0 [m] 0.93 [m 3 /s] Induction Siphon method Image of siphon intake 30

16 Special Application of Micro-Hydro Application to the Sewage Treatment Plant (2) Installation example to the sewage plant 31 Special Application of Micro-Hydro Application to the Waterworks (1) No of Turbine Max. Output Effective head Max. discharge Generator type 2 (S model) 170 [kw] 36.1 [m] 0.6 [m 3 /s] Induction Serial connection arrangement Instead of pressure reducer of waterworks 32

17 Special Application of Micro-Hydro Application to the Waterworks (2) Installation example to the Waterworks 33 Special Application of Micro-Hydro Pico Hydro 34

18 Project Cost of a Micro-hydro Plant Wide range of project cost of Micro-Hydro 1,000 to 15,000 US$/kW (in general) 2,000-5,000 US$/kW (by localized approach for rural electrification) Conditions affecting project cost Site conditions (River flow, Head, Topography, Length of transmission and distribution lines, etc.) Utilization of existing facilities (Irrigation intake, canal) Equipment to be used (Imported equip., Locally made equip.) Purpose of project (Lighting for rural electrification, industrial use) Way of power supply (Grid connected, Off-grid) Local approach? or not - Local technology - Locally fabricated turbine - Mobilization of local people as free labor 35 Project Cost of a Micro-hydro Plant Project Cost of a Micro-Hydro Plant in case of Local Approach In 2005 In 1985 Source: MICRO-HYDRO DESIGN MANUAL (Based on data in 1985) 36

19 Development Flow Development Flow Identification Identification of of Project Project Site Site Coordination Coordination with with Local Local Agencies Agencies Site Site Assessment Assessment Pre-Implementation Proposal Proposal Preparation Preparation Acquisition Acquisition of of Approval Approval & Permissions Permissions Organization Organization Formulation Formulation Monitoring Monitoring Training Training Construction Construction Operation Operation & Maintenance Maintenance Implementation O & M 38

20 Pre-Implementation Stage Government & Donors Power Utilities Power Utilities Proponent NGOs & Others Identification Identification of of Project Project Site Site Coordination Coordination Community Request Request for for Development Development Technical Technical Financial Financial Assistance Assistance Acquisition Acquisition of of Approval Approval and and Permission Permission Site Site Assessment Preparation Assessment of Site Survey Site Survey Water discharge and head measurement Investigation of of the site for the structure Demand survey Socio-economic survey Accessibility study Site Evaluation Proposal Preparation Proposal Preparation Layout Design Estimation of Project Costs Documentation 39 Implementation Stage Government & Donors Power Utilities Power Utilities Proponent NGOs & Others (QTP) Community Approval, Approval, Release Release of of Funds Funds Formulation Formulation of of O&M O&M Organization Organization Technical Technical Assistance Assistance Monitoring Monitoring Manual Manual Preparation Preparation Detailed Detailed Design Design Bidding and Bidding and Procurement Procurement Construction Construction Commissioning Commissioning Mobilization Mobilization General General Assembly Assembly Officers By-laws Tariff Rate Training Training Operators Operators and and Organization Organization Officers Officers 40

21 Operation & Maintenance Stage Government & Donors Power Utilities Power Utilities Proponent NGO & Others Community Handover Handover Feedback Report Operation Operation and and Maintenance Maintenance Management Management Monitoring Monitoring Monitoring Monitoring Tariff collection Bookkeeping Periodic reports Dialog with consumers Repair Repair and and Replacement Replacement 41