Small Hydropower: Design and Analysis

By Sunil Kumar Singal, Varun Goel, Himanshu Nautiyal and Dimitris Papantonis

Small Hydropower: Design and Analysis presents a comprehensive guide to the design, operation and maintenance of small hydropower plants. Using detailed diagrams and illustrations, the book examines the classifications, components, equipment, feasibility and analysis of each aspect of SHPs. Following a broad introduction, the book discusses classification approaches based on head, discharge, capacity, etc., analyzes site selection, and gives an overview of key development stages. SHP components for civil engineering works and electro-mechanical equipment have dedicated chapters that are followed by a chapter on how to design new components for the civil, mechanical and electrical aspects of a plant.

Subsequent chapters provide guidance on economic and financial analysis, environmental impact, troubleshooting and diagnosis in operating plants, and refurbishment and upgradation of SHPs, when and why this is needed, and how to approach it. Finally, several case studies provide real-world examples of SHPs in operation, giving readers insight into the practical needs of operating SHPs.

• Addresses all aspects of small hydropower, including civil works, hydro-mechanical, power generation and distribution, costing and financial analysis, environmental impact, and plant refurbishment and upgrading
• Provides dedicated chapters on the environmental and ecological impacts of small hydropower plants
• Assesses common problems in SHPs and provides tools for troubleshooting, diagnosis and solutions, including for site-specific issues
• Presents detailed real-world case studies showing the application of key aspects of SHP design, operation, maintenance, environmental and ecological assessment, and refurbishment

• Language: English
• Publisher: Elsevier Science
• Release date: Feb 19, 2023
• ISBN: 9780323986328

Sunil Kumar Singal

Sunil Kumar Singal is presently working as a Professor and Head of Department, Department of Hydro and Renewable Energy, Indian Institute of Technology Roorkee. Prof. Singal obtained his Ph.D. on Optimization of low head small hydro installations from the Indian Institute of Technology (IIT) Roorkee. He started his professional career as a Scientist at IIT Roorkee in 1984. He has more than 36 years of experience working on hydro energy and has successfully supervised 8 Ph.D. students and 80 Masters students in the fields of hydro energy and other renewable sources. Prof. Singal has published more than 200 technical manuscripts in the form of books, book chapters, journals, and conference proceedings. His research interests include small hydropower resource assessments and planning, designs of civil works, cost optimization and tariff analysis, integrated renewable energy systems, planning of water resources etc. He is a recipient of the Distinguished Scientist award- VIFRA 2015, Best Citizens of India Award – 2016, The Institution of Engineers (India) Excellence Award 2018, and Research Peace Award 2019-20.

Book preview

Front Cover for Small Hydropower - Design and Analysis - 1st edition - by Sunil Kumar Singal, Varun Goel, Himanshu Nautiyal, Dimitrios E. Papantonis

Small Hydropower

Design and Analysis

Sunil Kumar Singal

Department of Hydro and Renewable Energy, IIT Roorkee, Roorkee, India

Varun Goel

Mechanical Engineering Department, National Institute of Technology Hamirpur, Hamirpur, India

Himanshu Nautiyal

THDC Institute of Hydropower Engineering & Technology, Bhagirathipuram, Tehri, India

Dimitrios E. Papantonis

School of Mechanical Engineering, National Technical University of Athens, Zografos, Greece

Table of Contents

Cover Image

Title page

Copyright

About the authors

Preface

Acknowledgments

List of abbreviations

Chapter 1. Introduction to small hydropower

Abstract

1.1 Introduction

1.2 Summary

1.3 Exercise

1.4 For practice

Further reading

Chapter 2. Classification of small hydropower schemes

Abstract

2.1 Introduction

2.2 Definition of small hydropower

2.3 Classification

2.4 Summary

For practice

References

Chapter 3. Investigation and site selection for small hydropower system

Abstract

3.1 Introduction

3.2 Objective of site investigation

3.3 Preliminary investigation

3.4 Detailed investigations

3.5 Flow duration

3.6 Power equation

3.7 Power potential and installed capacity

3.8 Summary

Exercise

Further reading

Chapter 4. Components of civil works

Abstract

4.1 Introduction

4.2 Civil works components

4.3 Intake structure

4.4 Water conductor system

4.5 Cross-drainage structures

4.6 Desilting devices

4.7 Forebay

4.8 Surge tank

4.9 Penstock

4.10 Powerhouse building

4.11 Tailrace channel

4.12 Summary

Exercise

References

Further reading

Chapter 5. Elements of small hydropower: mechanical equipment

Abstract

5.1 Introduction

5.2 Trash rack

5.3 Gates

5.4 Valves

5.5 Hydraulic turbines

5.6 Unit’s bearings and lubrication system

Problems

References

Further reading

Chapter 6. Elements of small hydropower: electrical equipment and control

Abstract

6.1 Introduction

6.2 Electrical generators

6.3 Main transformer

6.4 Governors

6.5 Control, protection, and switch gear

6.6 Components for the reduction of hydraulic transients intensity

Problems

References

Further reading

Chapter 7. Elements of small hydropower plant: the powerhouse

Abstract

7.1 Introduction

7.2 Powerhouse of SHP with action turbines (Pelton, Turgo, and Cross-Flow)

7.3 Powerhouse of SHP with Francis turbines

7.4 Powerhouse of SHP with axial-flow turbines

7.5 Auxiliaries

7.6 Hydraulic forces on the basement of the powerhouse

Problems

Reference

Further reading

Chapter 8. Stages for development of small hydropower projects

Abstract

8.1 Introduction

8.2 Development stages of small hydropower projects

8.3 Project management necessity

8.4 Project management

8.5 Arrangements for the implementation of the project

8.6 Investigations

8.7 Small hydropower projects planning

8.8 Factors considered in planning

8.9 Planning methodology

8.10 Project implementation

8.11 Construction management for civil facilities

8.12 Management and installation of E&M equipment and its auxiliaries

8.13 Summary

Exercise

Further reading

Chapter 9. Economic and financial aspects of small hydropower

Abstract

9.1 Introduction

9.2 Estimation of cost

9.3 Financial terminology

9.4 Financial evaluation

9.5 Determination of tariff

9.6 Summary

Questions

Further reading

Chapter 10. Environmental impacts of small hydropower system

Abstract

10.1 Introduction

10.2 Sustainability of small hydropower projects

10.3 Environment impact assessment

10.4 Life cycle assessment

10.5 Small hydropower and circular economy

10.6 Environmental mitigation plan

10.7 Summary

Questions

References

Further reading

Chapter 11. Troubleshooting and fault diagnosis in small SHPs

Abstract

11.1 Introduction

11.2 Typical incidents in small hydropower plants

11.3 Maintenance

11.4 Diagnosis

11.5 Monitoring and measurement technology

Reference

Further reading

Chapter 12. Refurbishment and upgradation of small hydropower plants

Abstract

12.1 Introduction

12.2 Need of refurbishment and upgradation

12.3 Process of refurbishment

12.4 Case study: Louros SHP station

12.5 Summary

Questions

Further reading

Appendix A. Case study

A.1 Case Study I

A.2 Case study II

Index

Copyright

Elsevier

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About the authors

Sunil Kumar Singal is presently working as a professor and head of the Department of Hydro and Renewable Energy, Indian Institute of Technology Roorkee, India. Prof. Singal obtained his PhD degree in optimization of low-head small hydropower installations from the Indian Institute of Technology (IIT), Roorkee.

Varun Goel is working as an associate professor in the Department of Mechanical Engineering at the National Institute of Technology Hamirpur, India. His area of research includes renewable energy, heat transfer, CFD, and life cycle assessment.

Himanshu Nautiyal is an assistant professor and head of the Department of Mechanical Engineering at THDC Institute of Hydropower Engineering and Technology, India. His research areas include renewable energy technologies, sustainability, and life cycle assessment.

Dimitrios E. Papantonis is an emeritus professor at the National Technical University of Athens (NTUA), Greece, where he has been a professor since 1981. He is the former director of the Laboratory of Hydraulic Turbomachines, head of the School of Mechanical Engineering, and vice-rector at NTUA.

Preface

The development of small hydropower (SHP) projects has gained pace over the last three decades due to the growing concerns about the adverse issues associated with large hydropower. Before this, SHP projects used to be established to provide electricity in rural and remote areas as an alternative to diesel or fossil fuel-based power generation systems. But over time the need for SHP projects were recognized, especially due to concerns concentrated on environmental and climate change issues. Consequently, governments started to provide large subsidies for developers in order to identify and develop new sites and establishment of grid-interactive systems, as well as stand-alone SHP projects. The technologies associated with SHP also radiated over time. Various guidelines and parameters have been introduced to cover important aspects such as planning, finance, operation and maintenance, modernization, legal, and administration, for the effective development of SHP projects.

SHP is an appealing area for research where both academia and industries are assiduously involved, whereby academia and discovery-oriented research works are carried out in the view of learning. There is a great need to design courses which cover all aspects of SHP technology. Even industries are seeking such courses to prepare their engineers to become experts in the operation and maintenance of SHP stations. Moreover, various academic research and industry-customized PG programs housing different subdomains of hydropower, such as hydromechanical equipment, civil works, electricity generation and distribution, and environmental aspects, have been introduced and are prominent among students, researchers, and industry persons. A comprehensive book is substantially required, which comprises all aspects of SHP, from the planning of a project to its refurbishment and upgradation.

This book is written with up-to-date content and can be referred to for the various courses in SHP technology. It is also useful for those who are dealing with the planning, formulation, and designing of SHP projects. It includes investigations, the procedure of site selection, and stages of development of SHP projects. Separate chapters for civil works’ components, mechanical equipment, and electrical equipment and control are introduced. Additionally, a chapter on powerhouse is also presented to familiarize the basic knowledge of the locations of a powerhouse, which is based on various essential factors such as maximum safety, easy accessibility, and low cost. The basics and advanced techniques of SHP are emphasized for profound learning, especially for scholars and professionals. Further, it is beneficial for the owners and developers to explore the feasibility of the projects. Recent advancements in the area of SHP technology are included in the book. Moreover, the book also deals with the economic and financial analysis of SHP, including various financial terms, cost estimation, financial evaluation, and tariff calculation.

Environmental aspects of SHP projects along with various associated impacts and methodologies to estimate them are also covered in this book. Concise information is presented on SHP in the context of the circular economy too. Several issues and failures are encountered with the operation of SHP plants, which need to be resolved in order to achieve uninterrupted and efficient power generation. It is imperative to consider the fundamental knowledge of troubleshooting and diagnosis commonly faced in SHP plants. Thus a dedicated chapter on troubleshooting and diagnosis is included in the book. In addition, refurbishment, upgradation, and modernization of SHP projects, along with a case study, are also presented. The book also includes two case studies with original photographs for better understanding of SHP concepts with greater depth. Consequently, consulting engineers and planners can use this book as a reference while dealing with SHP projects. The book includes hard-earned knowledge and latest researches/studies to improve the quality of works in academia, as well as in industries, in context with accurate and realistic results.

Acknowledgments

We would like to express a deep sense of gratitude and thanks to our colleagues at the IIT Roorkee, NIT Hamirpur, THDC Institute of Hydropower Engineering & Technology, Tehri (India), and NTUA Greece for their support. We would like to thank HRED, IIT Roorkee, NIT Hamirpur, and THDC Institute of Hydropower and Technology for providing us the required data, without their support and help this task would not have been possible.

We also acknowledge the encouragement and support of our families who made many sacrifices during the preparation of this book. We are also thankful to the publishing team (Elsevier) who worked very hard in the type setting and formatting of the book.

List of abbreviations

APFR automatic power factor regulator

CDM clean development mechanism

CH4 methane

CO2 carbon dioxide

CO2eq CO2 equivalent

CPM critical path method

DG diesel generator

DPR detailed project report

DSCR debt service coverage ratio

E&M electrical and mechanical

EFR earth fault relay

EIA environment impact assessment

EMP environmental mitigation plan

EOT electric overhead traveling

FSL full supply level

GIS geographic information system

GHG green house gases

GPS global positioning system

GRP glass fiber reinforced plastics

GW giga watt

GWP global warming potential

HDPE high density polyethylene

HFL high flood level

HOT hand operated traveling

HRT head race tunnel

IRR internal rate of return

ISO International Organization for Standardization

kV kilo volt

kVA kilo volt ampere

kW kilo watt

LCA life cycle assessment

LCCA life cycle cost analysis

MDDL minimum drawdown level

MIV main inlet valve

MW mega watt

N2O nitrous oxide

NEA net energy analysis

NPV net present value

PAT pump as turbine

PERT program evaluation review technique

PLC programmable logic controllers

PMU project management unit

PPA power purchase agreement

PTFE polytetrafluoroethylene

PV present value

REC renewable energy certificate

RCC reinforced cement concrete

ROR run-of-the-river

ROW right-of-way

RS remote sensing

SCADA supervisory control and data acquisition

SETAC society of environmental toxicology and chemistry

SHP small hydropower

S-LCA social-life cycle assessment

UNEP United Nations Environmental Programme

WCS water conductor system

Chapter 1

Introduction to small hydropower

Abstract

Hydropower is one of the matured technologies under renewable energy based power generation. Earth’s hydrological cycle involves the evaporation of water from the earth’s surface, its rising, cooling, and then condensing into rain, cloud, etc., and falling back to the earth’s surface in the form of precipitation. The precipitation accumulates in rivers and water streams, which further evaporates, and the cycle is repeated again. This whole water cycle is completed with the help of sun’s heat and is further harnesed as hydropower. The power generation from water is a complex task involving high investments, formation of big reservoirs, large-scale construction, migration of population, etc. These issues are coming up as challenges in the further development of hydropower generation. Small hydropower (SHP) is an impressive solution to combat all these challenges and is also substantial in the context of sustainability. SHP projects are constructed relatively in smaller sizes and provide an effective solution to harness power through small water resources and streams. SHP technlogy can be used for localised power generation which plays a significant role in electrification of rural areas; as well as for feeding power grid networks.

Keywords

Small hydropower; head; energy; potential; water streams; electricity; generation

1.1 Introduction

Hydropower uses the energy of flowing water to drive machinery directly or generate electricity. The water cycle or hydrological cycle of the earth describes the evaporation of water from the earth’s surface, its rising, cooling, and then condensing into rain, cloud, etc., and falling back to the earth’s surface in the form of precipitation. The precipitation accumulates in rivers and water streams, which is further evaporated and the cycle is repeated again. The sun’s heat is responsible for evaporating water on the surface of natural water sources like lakes, rivers, and oceans. The complete water cycle is carried out with the help of solar energy which is further harnessed as hydropower. Therefore hydropower generation hinges on the amount of rainfall in the upstream catchment area. In other words, hydropower can be treated as an indirect manifestation of solar energy. The volume of precipitation collected in rivers, lakes, and water streams in any topographical area is used to figure out the potential of hydropower or water energy available for electricity generation. However, variation in precipitations due to climatic uncertainties such as declining rainfall, drought, and flash flood, affect the availability of water, which further greatly influences hydropower generation.

Hydropower generation does not involve any consumption of water but needs a continuous supply of water. There are two main components in a hydropower generation facility, viz., a water conductor system and electromechanical equipment. The process of generating electricity through water requires an ample amount of water or hydraulic energy. Before discussing about the hydraulic energy, it is necessary to understand from where the energy of water originates. The energy of water originates from the gravity or weight of the water, as it is commonly known that energy (in physics) is the capacity for doing work (energy primitive meaning: cannot be defined by other meanings directly). Work (in mechanics) is defined as the energy transferred by force, as shown in Fig. 1.1.

(1.1)

(the displacement in the direction of the force).

Figure 1.1 Concept of work.

Power is the rate (energy amount per time period) at which work is done or energy converted.

The scientific unit of power is the watt (W), which is equal to one Joule per second (time unit):

(1.2)

The weight F (N) is the force applied by gravity to a mass m (kg):

(1.3)

where g (m/s²) is the acceleration of gravity. The weight is always directed downward. If the mass m is moved vertically by the vertical distance h the work done is equal to as shown in Fig. 1.2.

(1.4)

Figure 1.2 Movement of mass vertically through distance h.

The units of the product (g·h) are: N-m/kg = J/kg

This work is negative when the direction of the movement by h is opposite to the direction of the force. If the mass m is lifted by h, then it is to be paid for this work (for example, to consume energy with an electrical lift). The work is positive when the movement of the mass m is downward, in the same direction as the force of the weight (as shown in Fig. 1.3).

Figure 1.3 Rotation of the rotor through downward movement of mass.

In the case that the mass m is from incompressible material of density ρ (kg/m³), as a liquid into a vessel, the mass m (kg) is related to the volume V (m³) of this mass by the relation:

(1.5)

Now, the work can be expressed as:

(1.6)

In the case of water moving into a pipe, we do not have a single mass m but a continuous succession of masses, the rate of which is equal to m˙ (kg/s) (as shown in Fig. 1.4).

Figure 1.4 Flow of water in a pipe.

For water (incompressible), the rate of mass is related to the rate of volume Q = dV/dt by the relation:

(1.7)

This is the case of water flowing with velocity "v (m/s) in a pipe with an internal section A" (m²): The flow rate is then equal to

(1.8)

The corresponding rate of work is defined as power. According to previous analysis:

(1.9)

From Eq. (1.9) it is clear that the prerequisites for the existence of potential hydraulic power (Ph) are the flow rate Q and level difference h (head). The Ph is the potential power that can be transformed into mechanical power on the rotating shaft of a hydraulic turbine and then into electrical power by the coupled electrical generator. This electrical power is then transferred to the electrical grid. This collectively is the principle of operation of a hydroelectric power plant, as shown in Fig. 1.5. The flow rate Q is the flow rate of a river, originated by the rain and the snow by an atmospheric phenomenon, and for this reason, hydraulic energy is renewable energy.

Figure 1.5 Principle of operation of hydraulic power plant.

The hydraulic energy depends on the quantity of water available, as well as on the elevation of the liquid surface, often termed as hydraulic head or simply head. Hence the total hydraulic energy per unit time available through any water source is estimated by using the available head and quantity of water flowing per unit time, that is, discharge.

(1.10)

The electrical power output can be estimated by multiplying the efficiency of the turbine and generator in the above equation.

(1.11)

In a hydropower facility, the energy of falling water is utilized to generate power; that is why water is stored in large, deep dams to get high potential energy that is further converted into electrical power through the turbine and generator. In a hydropower scheme, it is not possible to maintain the same water level always in the forebay (a small tank or storage built to regulate the flow) or reservoir due to the variation in the availability of water in a river or water resource. A pipe or conduit is used to convey the water from the storage to the turbine, known as Penstock. In the turbine section, water pushes the turbine’s blades causing the turbine to rotate, which further rotates the generator to generate electricity. Principally, the greater the head and discharge, the more hydropower can be generated.

The generation of electricity from water is quite a mature technology. In fact, mankind has been using the water force of rivers and streams through water wheels to produce mechanical energy for a long period of time. The concept of electricity generation from water power came up in the 19th century when the first hydroelectric power station was established in the United States in 1882. However, the first hydroelectric power setup was supposed to have been installed in Northumberland, England, by William Armstrong in 1878, which was used to power a single lamp. The main advantage of the introduction of electricity is the disconnection of energy production from energy consumption. The result was the construction of large power plants. After that, the technology became more popular over the time, especially for power generation. The technology advancements in civil works, construction of dams for storage of large volumes of water, efficient hydromechanical equipment, alternators, etc., made hydropower the most attractive power generation technology. Today thousands of MW of electricity can be easily produced in hydropower facilities throughout the world, and the total global capacity of hydropower generations has now crossed 1100 GW. In fact, hydropower comes first among all renewable energy sources due to the various benefits associated with it. It has soared throughout the world, and almost all nations are trying to increase their hydropower generation capacity. Therefore harnessing hydropower through the water resources not only helps in generating electricity but also makes the nations more independent in respect of the availability of clean power and reduction of consumption of conventional fossil fuels and petroleum products. One of the distinctive features of hydropower is that it is capable of providing various benefits over and above power generation. In other words, hydropower development strengthens the economy of nations and provides several social benefits in terms of employment, tourism, irrigation, fisheries, flood control, business opportunities, etc. In this way, hydropower can be considered to be a versatile technology for its ability to provide economic and social development in a region. However, the main objective of establishing a hydropower plant is electricity generation in almost all cases. As compared to other renewable energy sources like solar and wind, the major advantage of using hydropower is the continuous availability of water. Hydropower demands no requirement of electricity storage devices or systems as necessarily required in solar and wind power plants, and this provides greater flexibility in the operation of hydropower plants in power grids. Overall, the relatively low cost of electricity generation in hydropower projects makes them more attractive and competitive in the power sector.

Besides all these advantages, hydropower-based electricity generation is a clean source and discharges lesser emissions into the atmosphere as compared to conventional and fossil fuel-based power plants. Here lesser emissions mean emissions associated with construction and operational processes in hydropower projects. These emissions and their other associated factors will be discussed in the upcoming chapters. Also, there is no involvement of direct combustion of any kind of fuel in hydropower plants for power generation as in the case of conventional energy-based power plants.

1.1.1 Need for small hydropower

There are so many benefits associated with hydropower, and this was the reason that hydropower generation increased very fast in the last few decades. The large hydropower facilities store large volumes of water in big reservoirs and hence involve submergence of large areas of land. Big dams ensure continuous water flow, which is important for uninterrupted power generation. They are able to store water when surplus is available in rivers and utilize the stored water during lean flow or seasonal abatement. Besides continuous power generation, dams are quite advantageous in controlling floods, irrigation, water supply, etc. The size of the reservoir is solely dependent on the installation capacity and topography of the area. But along with this growth, some impediments associated with hydropower development have been noticed, which were difficult to be neglected. For example, reservoirs in hilly areas are constructed with greater depths in smaller regions, whereas in plain terrains, the construction of reservoirs involves more areas and lesser depth. Consequently, there are some variations in installation of power stations in hilly and plain regions in terms of construction, machinery, etc. The permanent land occupancy for the construction of reservoirs involves the submergence of land that may be a kind of forest area, wildlife area, arable land, or a well-populated area. This submergence of land creates a great need for large-scale rehabilitation of communities. Moreover, construction of reservoirs and then rehabilitation of the population occupy the land far more. For rehabilitating specific population, which may be a village, town, or sometimes a city, a new region or area is required. In most cases, this new rehabilitation site is a forest or agricultural land, where the whole population has to be shifted and colonized. In this way, dam constructions not only occupy and affect the submerged land but also require the land in other areas or regions where the population is rehabilitated.

Large dams associated with hydropower also affect the wild and aquatic life around it. Deterioration of aquatic life due to the operation of machineries in power plants and obstruction of water flow, especially downstream, affect the aquatic life, and this may create an imbalance in aquatic life in the upstream and downstream regions. Moreover, a large volume of stored water often promotes the formation of weeds, algae blooms, etc., due to large-scale nutrients and sediment deposition, which further strengthen this aquatic imbalance. This is due to the fact that almost all power plants are installed across the rivers, which creates severe possibilities of disturbing the aquatic ecosystem of that region. Besides this, many studies reported the release of high amounts of GHG emissions in the construction and operation of hydropower projects. Decomposition of vegetated land and soil in submerged areas promote the generation of GHG gases like methane and CO2, into the atmosphere. Hydropower dams are also responsible for causing a large amount of artificial evaporation into the atmosphere due to their large exposed water surface area. Moreover, land surfaces consume water by direct evaporation and transpiration through vegetation and further affect evapotranspiration of the region. The storage water in the reservoir and downstream side of the river are also impulsive in eutrophication of the lake. All these phenomena, like evapotranspiration, seepage losses, thermal stratification, and nutrient level variations cause strong ecological stresses. In this manner, large hydropower projects are now considered to cause various adverse environmental impacts.

In view of the above-discussed issues, there is one more important problem that arises with the establishment of large hydropower plants. In fact, it is mostly seen that it takes quite a long time to set up large hydropower facilities. Large-scale constructions, installation of heavy machineries, and rehabilitation of communities consume a lot of time, and in most cases, there arise possibilities of social interference, which further increase the time of deployment and increases the delay. Large hydropower schemes are already costly and more delays due to these issues further augment the cost of the projects and energy payback periods. Therefore all these issues raise a big question in front of environmentalists and policymakers on the sustainability of large hydropower schemes. All the above impediments associated with large hydropower projects strongly promote the generation of hydropower at a smaller level, and from here, the concept of small hydropower (SHP) is introduced.

The generation of hydropower at a small scale is quite beneficial and a promising alternative to avoid the problems associated with large hydropower schemes. The definition of SHP is mostly dependent on the installed capacity of power plants. SHP projects are relatively smaller in size and can be utilized to generate electricity from small water resources and streams. They have also proved to be a big contributor to solve the problem of rural electrification, as well as feeding power to grid networks. In fact, SHP is an effective solution to mitigate the problems of electrification in isolated and rural areas and thus promote the development of the region. There is no common definition existing for defining SHP projects, as different countries follow different limits of power output ranging from 5 MW to 50 MW. For example, hydropower projects with a capacity upto 25 MW are considered as SHP in India, 50 MW in China, and 30 MW in the United States. Furthermore, SHP projects can be classified as Micro, Mini, and small projects. Again, this definition of installation capacities in the classification of micro, mini, and small projects may