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L.B. Kassana

L.B. Kassana/Training Workshop for GTIEA

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L.B. Kassana

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    1. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 1 Tuesday, April 03, 2012

    2. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 2 Presentation Outline: Hydropower in General Fundamentals of Small Hydro Technologies Barriers to the Development & Implementation of SHP New Financing Model for SHP

    3. 3 L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 Tuesday, April 03, 2012 Hydropower in General Aspects How Hydropower Works

    4. 4 L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007

    5. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 5 Tuesday, April 03, 2012 Types of Hydropower Facilities

    6. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 6 Tuesday, April 03, 2012 Advantages and Disadvantages of Hydropower

    7. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 7 Tuesday, April 03, 2012 Advantages and Disadvantages of Hydropower - cont

    8. 8 L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 Tuesday, April 03, 2012

    9. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 9 Tuesday, April 03, 2012 Introduction to Small Scale Hydropower 1st Question: Why bother develop it after all?' Why not leave waterfalls and the beautiful landscape intact? Exercise for the participants!! The following elements will be covered: The Process of Evaluating a Site The water resources and its potential Civil Engineering Works Electromechanical Equipment Economical Considerations & Evaluation

    10. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 10 Tuesday, April 03, 2012 The Process of Evaluating a Site Identification of the Site Evaluation of the water resources available for the plant and consequentially its annual energy production Preliminary Definition and Cost Evaluation of the Plant Preliminary Evaluation of Economics of the Scheme after researching on financial alternatives, benefits available from governments, tax incentives, etc. Review of Regulatory requirements and its administrative procedures.

    11. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 11 Tuesday, April 03, 2012 The Water Resources and its Potential Hydrology: Velocity-Area method Dilution Methods Flow measuring structures e.g rectangular weir, V-noth weirs, flumes. Slope-Area method: Sizing a power plant: FDC provides means of determining quickly how much of the available water resources can be used by turbines of different sizes. Power available from flow varies with time since Q is varying & is given by P = QH?? where Q is discharge, H is net head, ? is specific weight of water (9.81 kN/m3), ? is overall efficiency (may initially est. to be 0.8). Annual energy production: Can be estimated to a 1st approximation by measuring the usable area under the FDC, converting to an actual qty of water in m3 in a specific time, multiplying that by 9.8 and the net head (averaged) and mean efficiency (estimated). The result is annual energy in kJ which is converted to kWh by dividing by 3600.

    12. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 12 Tuesday, April 03, 2012 Typical Basic Layout & Schematic Diagram

    13. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 13 Tuesday, April 03, 2012 Civil Engineering Works Dams/Weirs: has 2 functions: To increase the available head To create a reservoir to store water Intakes: have the following functions: To conduct water into the penstock or power canal/tunnel To minimise the amount of debris and sediment carried by the incoming water. Waterways: Tunnels/Canals: these convey water either directly or via penstock to the turbines Forebay: designed to provide only enough storage to provide extra volume needed during the turbine start-up Penstocks: these are pressure pipes conveying water to the turbines Tailraces: these return water back to rivers after passing thru the turbines Powerhouse: location for turbines, generators, etc <100 m head, the size of P/Hse & concrete volume are a function of turbine size >100 m head, the size is governed by diameter of the generator casing.

    14. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 14 Tuesday, April 03, 2012 Electromechanical Equipment Hydraulic Turbines: They convert potential energy to mechanical energy. 3 categories of conventional turbines: Kaplan & Propeller turbines: these are axial flow reaction turbines used for low head Francis turbines: these are radial flow reaction turbines with fixed runner blades and adjustable guide vanes used for medium heads. Peltons: these are impulse turbines with single or multiple jets, each jet issuing thru a nozzle with a needle to control the flow. They are used for both medium and high heads.

    15. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 15 Tuesday, April 03, 2012 Electromechanical Equipment-cont. Classification of Turbine types

    16. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 16 Tuesday, April 03, 2012 Electromechanical Equipment-cont.

    17. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 17 Tuesday, April 03, 2012 Electromechanical Equipment - cont Turbines: Type, geometry and dimensions depends primarily on: Net head Rated (design) discharge Specific speed, Ns: determines the type & basic shape of the runner & other parts of the unit. N=Ns*H(5/4)/vP where N is synchronous speed in rpm (N=(60f)/#of poles), H is head and P is power Runaway speed: theoretical speed that can be attained when hydraulic power is at its max and electrical load is disconnected. Ratio power to net head: Cost, of course!!

    18. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 18 Tuesday, April 03, 2012 Electromechanical Equipment-cont. Generators: these transform mechanical energy to electrical energy. There are two choices: Synchronous alternators equiped witha DC excitation system and Asynchronous Generator which draws excitation from the grid. Control equipment: Governors that can be mechanical or electrical Switchgear panel and protection Automatic control Powerstation auxiliary electrical equipment Station service transformer DC control power supply Outdoor substation

    19. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 19 Tuesday, April 03, 2012 Economical Considerations Preamble: Profitability of a scheme is a function its capital and of the revenues from the sale of electricity. Main parameters influencing costs and revenues: Type of turbine Number of Units; turbines with murtiple runners or multiple nozzles Speed of rotation Turbine setting Control equipment Size of powerhouse Sale of electricity

    20. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 20 Tuesday, April 03, 2012 Economical Considerations-cont Type of turbine: For the same head, certain turbines are more difficulty to manufacture than others consequently they are more expensive. E.g for low heads, a Propeller is cheaper than a Kaplan designed for the same rated discharge. In medium heads, a cross-flow turbine is cheaper than a Francis whose runner is more complex. Number of Units: Turbines with multiple runners or multiple nozzles Speed of Rotation: Higher specific speed mean smaller turbine dimensions and higher speed generators. Since the turbine cost decreases with an increase in speed, there is a major incentive to use ever higher specific speed. Furthermore, in small units, if the speed is high enough, a standard generator may be directly coupled to the turbine, thus saving the cost of the gear box

    21. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 21 Tuesday, April 03, 2012 Economical Considerations-cont Turbine Setting The negative aspect of high specific speeds, requiring a deeper setting to avoid cavitation, must also be included in the assessment: Additional foundation excavation Extra dewatering costs Higher costs of draft tube gate because of higher tailwater head etc Control Equipment Turbines like Kaplan with double regulation (if both runner blades & guide vanes are adjustable) require a more complex control system that increases the costs. But others like the Pelton wheel accept rather rudimentary control system like a deflector infront of the nozzle.

    22. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 22 Tuesday, April 03, 2012 Economical Considerations-cont Size of the Powerhouse The powerhouse concrete volume can be determined based on a number of units and their throat diameter. Often the cost of the civil work is higher than the cost of the equipment. Reducing the cost of the unit size decreases the cost of the powerhouse. Sales of electricity The revenue from the sale of electricity produced by one unit is given by the following equation: R=9.81*Q*Hn*nTa where Q is discharge in m3/s Hn is net head in m n is overall efficiency of the system = running time Ta is electricity tarriff

    23. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 23 Tuesday, April 03, 2012 Economical Evaluation Static Methods: Payback (recovery or break even period) Method: determines # of years required for invested capital to be offset by resulting benefits. Return on Investment Method: calculates average annual, net of yearly costs, such as depreciation, as a percentage of the original book value of the investment. Dynamic Methods: these take into account total costs & benefits over the life of the investiment and the timing of the cash flow Net Present Value (NPV) Benefit-Cost ratio (B/C) Internal Rate of Return (IRR)

    24. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 24 C. Barriers Challenging the Development & Implementation of SHPs Investor confidence is lacking Financing: Financial institutions are generally not familiar with small hydropower sector. Technical capability: The engineering and consulting firms in Africa have limited experience with carrying out F/S, design & Construction of SHP. Without high quality assessment & F/S then investment will not come in this sector Lack of infrastructure for manufacturing, installation and operation. Most of the countries in Africa do not have any facility to manufacture even the most rudimentary turbines or parts that might be critical in maintenance of the schemes.

    25. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 25 Barriers Challenging the Development & Implementation of SHPs - cont Policy & Regulatory uncertainty: Gvt policies in most EATTA countries generally support development of SHP but there are no clear targeted regulations & incentives for specifically promoting independent generation for captive use or for feeding into the grid and public private partnership for rural electrification. Market Uncertainty: lack of clear rules to allow the sale of power produced by SHP, say beyond tea factory limits the size of projects & reduces # of financially attractive SHP. Lack of entrepreneurial Culture amongst our selves i.e. cant take calc. risks, determination, perseverance, creativity

    26. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 26 D. New Financing Model for SHP This is an entrepreneurial centered approach featuring a combination of services and financing. Under this model, a financier works to bring small, privately owned companies together with a commercial investor to back SHPs. The financier provides a range of services to privately owned coys who want to supply clean electricity to their factories and communities around to help them improve their lives and income The financier provides the following services: Accepting project risks Offering convertible debt (i.e. Debt that may be converted to equity) at reasonably attractive terms. Providing debt and equity financing options appropriate for the size of the entreprise and market conditions Providing support services to the developer b4 and after an investment Forstering partnership and relationship with social investors and partial risk sharing lenders

    27. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 27 D. New Financing Model for SHP - cont The entrepreneurial model should work as follows: The financier provides first the seed money to pay for legal, engineering or environmental preparation The funding can range from USD 100,000 to USD 3 Million depending on the size of the project and it is a case by case. For our case, if we are superimpose GTIEA Project - FSP phase on this model, the seed money comes to about USD 2.8 Million. The financier acts like as an advisor helping and entrepreneur with the business plan development , working with banks to get the construction funding, negotiating PPAs and training developers on approaches to business management and expansion. Once an enterprise begin to meet its objectives, it may be appropriate to provide a growth loan

    28. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 28 D. New Financing Model for SHP - cont The entrepreneurial model would look like:

    29. L.B. Kassana/Training Workshop for GTIEA & Cogen Africa Projects -Nairobi Kenya, Nov 9-10, 2007 29 CONCLUSION

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