Small Hydraulic Turbin Hanbook

8/14/2019 Small Hydraulic Turbin Hanbook

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Small HydroPower Handbook

A Guide toUnderstanding

and ConstructingYour Own Small

Hydro Project

Indroduction

CHAPTER #1 -ENERGY FROM WATER - IS YOUR PROJECT WORTH

PERSUING?

CHAPTER #2 - SITE EXPLORATION AND STREAMFLOW DATA

CHAPTER #3 - ASSESSMENT OF THE FEASABILITY OF YOUR HYDRO SITE

CHAPTER #4 - CIVIL WORKS AND EQUIPMENT

CHAPTER #5 - PERMITS, LICENSES AND LEGAL ASPECTS FOR SMALL

HYDRO

CHAPTER #6 - ECONOMICS AND FINANCING

CHAPTER #7 - GETTING STARTED

CHAPTER #8 - LOW HEAD CONSIDERATIONS

CHAPTER #9 - COLD WEATHER CONSIDERATIONS

CHAPTER #10 - ORGANIZATION AND OPERATION OF A PUBLIC UTILITY

GLOSSARY

INTRODUCTION (Chapter 1 Index)

Why Small Hydro

British Columbia offers enormous small hydro potential to its inhabitants: about 2400

MW, with 550 sites near the grid. Small Hydro is part of the history of British

Columbia. Many early mills, mines and towns built some form of power generation

from small hydro, in the late 19th and early 20th centuries; and waterwheels were
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used much earlier - in Ashcroft, in 1863, for example. Most of these old sites have

fallen into disuse by now - rendered uneconomic in the 1950's by the availability of

cheaper electricity through an expanding, province-wide grid; and by the availability

of portable, flexible, low cost diesel generators. Diesel generators are still cheap to buy

- but the rise in the cost of oil has made them expensive to operate. And the provinces

electrical grid, while extensive, does not include a number of small communities,

resource-based businesses, farmers, and lodge owners: people in out of the way

locations who are paying an enormous cost for their independent way of life. Such

people are taking another look at water power, because it offers a stable, inflation-

proof source of electricity, using proven technology. Small hydro installations have,

historically, been cheap to run but expensive to build. That is changing now, with

smaller, lighter, and higher speed turbine equipment, lower cost electronic speed and

load control systems, and inexpensive plastic piping. Capital investments are still

higher than investing in diesel equipment of comparable capacity; but the long life and

low operating costs of small hydro make it an attractive investment for manyapplications. Examples of such installations, built in B.C. during the past few years,

include: Glacier Park (150 kW); Hoeya Hilton (37 kW); Nimmo Bay (40 kW); Hasty

Creek (37 kW); Klemtu (650 kW); Kingcome (75 kW); and Rendell Creek Ranch.

Some very small, and very successful units have been installed by entrepreneurs - a

farmer in the Pemberton Valley, for example (25 kW). other, larger units, have been

build by entrepreneurs who then sell power on contract to a resource industry -

Lancaster Resources (now Synex) at Moses Inlet, selling to Crown Lumber. There are

business opportunities in small hydro - and a number of people are catching on.

Purpose of the Manual

This book is written to assist people who are interested in developing a small hydro

opportunity. It will be especially useful to people with small sites that would not justify

the expense of extensive professional engineering services. Even with small sites, such

services may be advisable if you have conditions you do not fully understand. The

book will provide you with the information you need to: - evaluate the potential of a

small hydro site; - lay out the site; - apply for necessary licences and permits; - get

financing; - select and install equipment and - understand the equipment, so that you

can operate and maintain the system yourself. The emphasis in the book is on doing as

much as possible yourself, thus keeping capital costs as low as possible. However,

advice on seeking professional help is also included - and the information contained inthese chapters will be invaluable to you in dealing with any consultants and

contractors you hire. Actual construction details are not included; general guidelines

are given, along with pointers on what help can be expected from a construction

contractor. The book does not assume any previous acquaintance with the subject.

mathematical procedures are generally limited to multiplication and division for the

fundamentals. (more sophisticated procedures may yield greater accuracy, but the

simpler procedures outlined here should be sufficient for the scope of projects

intended.) A hydro turbine generator can by very small, like the alternator for a car

(c. 500 Watts); or it can be very large, like the units at the Revelstoke Dam (several

thousands of millions of Watts). microhydro (1-100 kW) and mini-hydro plants (100

kW to 5 MW) are the smallest of the turbine generator units. This handbook is aimedmainly at installations of less than 500 kW, although it covers licensing requirements


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up to 20 mw. The writers of the chapters that follow are all experts in their fields, and

have all written as clearly and simply as possible. It will take time and study, however,

to thoroughly understand each section of the book especially the charts, tables, and

graphs. The effort will pay off: your chances of bringing a project to a successful

completion, producing reliable energy year after year, and significantly improving

your cash flow, will be greatly enhanced.

Cost of Development

Costs for smally hydro installations vary considerably, because sites, conditions and

sizes are all different. In 1985, the typical development can range from $1,500 to

$5,000 per installed kW. This would mean an investment of from $6,000 to $20,000 for

the "typical" simple family home, which requires a peak demand of 5 kW. (If that

home were using electric heating, the demand would be from 12-20 kW.) This

handbook shows how to estimate installation cost, and how to balance designtradeoffs, cost, and projected energy production. You can significantly reduce costs by

clever management, procurement, and hard work. The system at Rendell Creek

Ranch cost only $25,000 for a 150 kW system - less than $200 per kW - because the

community did most of the work itself and was able to buy and rebuild used

equipment. In approaching costs, remember that there are two basic types of

developers: those who are interested in generating to meet only their own needs,

regardless of the site's potential; and those who want to get as much as possible out of

the site. Costs for the former developer will generally be lower because the system will

be smaller, and geared both to minimum requirements and minimum flow. Investment

for the latter will be higher, but the per kW cost may be less.

Organization of the Manual

You are encouraged to peruse the book and gain a general knowledge of its contents

before starting actual development. Chapters One, Two and Three represent the

major steps for any site development. Chapter Four then treats dams, intakes,

penstock, turbines and all equipment associated with the manufacture of a small

hydro site, in considerable detail. Chapter Five serves as a guide to developers on the

legal aspects of permits, licences and insurance. This is a weighty section, but an

understanding of the requirements is essential. Chapter Six, on Economics and

Financing, takes you through the economic feasibility of the project and helps you

decide on the economics of the project. Chapter Seven is subtitled "Getting Started".

It gives the developer some practical tips on the many logistical steps necessary to

carry through with the project, once it is designed. It will help get the project started

and help you make sure it is completed. Chapters Eight and Nine are specialized

chapters on Low Head and Cold Weather Considerations. If you are working under

either of these constraints, these chapters should be read carefully. Chapter 10 outlines

the requirements for setting up a utility, should you wish to sell your surplus power.

CHAPTER #1 - ENERGY FROM WATER - IS YOUR PROJECT WORTH

PERSUING?
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1.1 ..........Introduction

1.2 ..........Your Power Requirements

1.3 ..........Power and Energy Definitions

1.4 ..........Data Collection

1.5 ..........Installations

1.6 ..........Available Power and Energy

1.7 ..........Advisors

1.8 ..........Project Costs

1.9 ..........Project Worth

1.10 ..........Continued Planning

1.11 ..........Project Data Summary

SUPPLEMENT / MEASURING HEAD AND STREAMFLOW / PRELIMINARY

1.1 ..........Introduction (Back)

Perhaps you are living close to a stream and you are considering building a small

hydro project on it. Or perhaps you are starting to plan a project and you are looking

for a suitable stream. In either case this chapter will help you. Chapter One covers: (a)

The fundamentals of providing electrical energy from water; (b) the process of

selecting a suitable stream and a site for a hydro project; (c) the simple calculations

for helping you to decide whether you should continue planning your project, or

whether you should start looking for some other way of getting electricity; and (d) the

costs, procedures and time requirements of hiring an engineer to do the preliminary

work. Probably your most valuable experience is to have lived next to a stream for

several years and to have noted the fluctuations in its flow: how high and low it can go,

how soon it reacts to a rainstorm, and how the stream changes its course when in

flood. However, without this background knowledge you will still be able to build a

good hydro project. To help you decide whether or not to continue with your the

project, you will be asked to (a) estimate the power you need; (b) estimate the

streamflow available; (c) measure or estimate the head available on the stream; (d)

estimate the power and energy available from the stream; (e) make a preliminary

layout of your project; (f) make a preliminary estimate of the cost of your project; and

(g) decide: "Is your project worth pursuing?" Each time you make an estimate or

calculation, you should enter it in Table 1.3, "Project Data Summary" at the end ofthis chapter. If you have already decided to continue planning, you should still skim
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through this Chapter and check that you have the data listed under all the headings in

Table 1.3.

1.2 ..........Your Power Requirements (Back)

First, you need to estimate how much power and energy you use at present, and how

much you will use, say, ten years from now. Normally some degree of load

management is used in mini-hydro plants. The loads shown in Table 1.1 assume some

degree of load management.

1.2.2 Load Estimates

An approximate estimate of the load will do at this stage. A more accurate estimate

will be made in Chapter 3. Using Table 1.1 to estimate your peak winter and summer

loads, select a value within the ranges given. These ranges indicate the difference inloads due to different living styles and different climates. Take account of the

appliances you have, compared to those listed in the table, and the conservation or

extravagance in your use of electricity. Also consider the climate where you live: you

will use more electricity in the interior and northern parts of B.C. than you will on the

coast, on Vancouver Island, or in the Lower Mainland. Following the example below,

write down your expected future peak load value for the winter (November-April) and

summer (July-October). Use a future of 10 years time or whatever time span you wish

to consider for the hydro plant. If you want to make a more detailed estimate, turn to

the section on "Power and Energy Requirements" in Chapter 3. Do this only if you

want to learn more about load management: it gets quite complicated. Example: A

single family house with 2 bedrooms and workshop - electric lights, washer, drier,fridge, freezer, kitchen appliances (no oil, propane or wood cooking stove), baseboard

and hot water heating, table saw, small hand tools. From Table 1.1: (In this example

case 3B, a 3 bedroom house without back-up for heating, is used to allow for additions

in the future.) Example Your Expected Loads Winter Maximum Load 12

kW ................ kW Summer Maximum Load 5 kW ................ kW (Write these values at

the top of Table 1.3)

1.2.3 Energy Conservation

Do you conserve energy as much as you can? Have you considered the following ways

of reducing your energy consumption, and thereby reducing your costs? - upgradinginsulation in basements, floors, walls, cedilings and attic; - adding storm windows or

double or triple glazing; - reducing air leaks by caulking and weatherstripping round

dorrs and windows; - servicing the oil or propane furnace and water heater; -

insulating the hot water tank and pipes;

1.3 ..........Power and Energy Definitions (Back)

The methods for calculating power and energy that are available from a stream are

covered in this section.
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1.3.1 ..........Power

The calculation of the actual power from your stream is covered in Section 1.6, after

you have measured or estimated the flow and head. The theoretical power equation

(Equation 1-1) is P= Q x H x e x 9.81 Kilowatts (kW) (1-1) Where: P = Power at the

generator terminal, in kilowatts (kW). Q = Flow in pipeline, in cubic metres per

second (m3/s). H = The gross head from the pipeline intake to the tailwater, in metres

(m) (see Figure 1.2). e = The efficiency of the plant, considering head loss in the

pipeline and the efficiency of the turbine and generator, expressed by a decimal (ie

85% efficiency 0.85) 9.81 = Constant for converting flow and head to kilowatts. All

power systems produce less power than is theoretically available. The losses in a hydro

plant are: (a) losses in energy caused by flow disturbances at the intake to the pipeline,

friction in the pipeline, and further flow disturbances at valves and bends; and (b)

losses of power caused by friction and design inefficiencies in the turbine and

generator. The energy losses in the pipeline and at valves and bends, are called headlosses: they represent the difference between the gross head and the net head that is

available at the turbine (see Figure 1.2). The head losses in the pipeline could range

from 5 percent to 15 percent of the gross head, . depending on the length of the

pipeline and the velocity of the flow. The maximum turbine efficiency could range

from 80 percent to 90 percent depending on the type of turbine, and the generator

efficiency will be about 90 percent. At this stage in the planning of your hydro plant,

the head losses can be combined with the losses in the tubine and generator, and an

overall plant efficiency of 60 percent (or e = 0.60) can be used. Using e = 0.60 in

Equation 1-1, the actual power output at the generator can be calculated from the

following Equation 1-2: P x H x 5.9 (kW) (1-2) The Power Output Nomograph in

Figure 1.3 enables you to make quick estimates of power, flow or head. Example:Suppose you know the lowest flow (discharge) in the stream (say 0.1 M3/s or 100 L/s),

and you know where to put the intake and powerhouse so you can estimate the head

(say 10 m). Example Your Values Flow 100 L/s L/s Head 10 m M In Figure 1.3 mark a

point (in pencil) at a flow of 100 L/s on the DISCHARGE (left) scale; on the HEAD

(right) scale mark a point at a head of 10 m. Draw a straight line between the two

points and where this line intersects the POWER (middle) scale is the estimated

power, in this case 5.9 kW. Power 5:9 kw' kW If you have been using your own values

of flow and head, and find that the power output is not enough for your power

requirements, don't worry: you're just trying out the nomograph. Later in this

chapter you will make the proper calculations. Other ways of using the nomograph

are: (a) to find the necessary flow, provided you know your power requirements andcan estimate the head available on the stream. Extend a straight line from the HEAD

scale through the POWER output scale and onto the DISCHARGE scale, or, (b) to

find the necessary head, provided you know your power requirements and can

estimate the minimum flow in the stream. 1-6 1.3.2 Energy The equation to calculate

energy is E = P x time Where: E = Energy, in kilowatt - hours (kW.h) P = Power, in

kilowatts kW Time = Time while power is generated or used Example: If you run a

1000 watt (1 kW) electric heater for 5 hours you use 5 kW.h of energy.

1.4 ..........Data Collection(Back)

Streamflow, head and pipeline length must be estimated or measured, before you can
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calculate the power that could be developed from a stream. Streamflow is the most

difficult to measure or estimate. However you should have an understanding of its

sources, its fluctuations and flow measurements or estimates.

1.4.1 Streamflow

Streamflow comes from either rain or melting snow, but not all the rain or melting

snow immediately becomes streamflow. There are losses caused by evaporation from

the ground surface, transpiration by the vegetation whose roots have absorbed

moisture from the ground and from seepage or surface water into the ground to

become groundwater. This groundwater can take weeks or months to appear as

streamflow, and is therefore not available for power immediately after rain or

snowmelt. However, this groundwater is important, the major component of the

streamflow during dry periods in the summer or winter. A hydro project should be

designed for these dry, low flow periods. It is advised that you check both Fisheriesand Water Licenses statutes of the creek prior to doing much work, it might belong to

someone else.

Streamflow Fluctuations

We all know that streamflow fluctuates, often daily, always seasonally and yearly. To

visualise these fluctuations, values of flow are plotted against time, as shown on Figure

1.4 (A and B) these plots are called hydrographs. In Figures 1.4.A and 1.4B,

hydrographs of flows in 1980 are shown for six rivers in five different parts of B.C.

Notice the different patterns of flow in different parts of the province. The simplest

pattern is for Beatton Creek in southeast Interior (Figure 1.4A): (a) low flows inJanuary to March (cold weather). (b) rapidly increasing flows in April (snowmelt). (c)

high, erratic flows in May and June (snowmelt plus rain). steadily decreasing flows in

July and August (no further snowmelt). (d) low flows again through the winter. Brouse

Creek (Figure 1.4A), in the same area as Beatton Creek, is much smaller. The pattern

for these two creeks is similar except that in Brouse Creek the major snowmelt period

is in May only. Moving westward to the Coquihala River (Figure 1.4A), the effect of

winter rain is reflected in the extremely sharp peaks in December. A pronounced

snowmelt period lasted from April until June, and prolonged low flow periods

occurred in January and February and again between August and October. In the

North, the Cottonwood River hydrograph (Figure 1.4B) shows the prolonged low flows

caused by low temperatures from December through to the end of April. West of theCoast Mountains, the Little Wedeene River hydrograph (Figure 1.4B) shows the effect

of heavy rain from September to December. The snowmelt period, April to June is not

so obvious because of the erratic rain peaks superimposed. Short periods of low flows

occurred in most months January - March and August - October. In the Northern

part of Vancouver Island, the pattern of flows for the Ucona River is less distinct;

erratic flows during the winter (rain and snowmelt), fairly steady flows April - June

(snowmelt), then decreasing flows to September (little rain). Knowing these patterns

will help you choose the right time of year to measure low flows and average flows.

You will also recognize the relation between low, average and high flows; this will

enable you to check the magnitude of your measurements or estimates.


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Streamflow Measurements and Estimates While many larger streams and rivers in

B.C. have gauges installed by Federal or Provincial Government agencies, it is unlikely

that there will be a gauge on your stream. You will probably have to measure or

estimate the flow. There are several ways to measure flow: 1-8 (a) use a float to

measure velocity and a level and tape to measure the stream cross-section, (b)

construct a weir (A weir is a low dam over which the water flows) across the stream

and measure water levels or, (c) use a flow-meter to measure velocity, and a level and

tape to measure the stream cross-section. using a float is the easiest but the least

accurate method. Building a weir or using a flow-meter are the best methods for

establishing a semi-permanent measuring station to obtain flows for several months or

years. At this stage in the planning process, you should use the float method described

in Supplement 1 . 1 (at end of this chapter). What flows should be measured? This will

depend on the amount of water the hydro plant will take from the stream compared to

the minimum flow in the stream. You need to get an overall picture of the variations in

the flow of the stream. But the lowest flow is usually the most important because it canlimit the maximum power that can be produced. At this stage, you don't know how

much flow the hydro plant will take. But it is helpful, when deciding what stream flow

to measure, to keep in mind three situations: 1. The stream is large and only a small

portion of the lowest f low is needed for your hydro plant. If you know that you will

always have enough water for the plant. You don't have to measure the flow; you can

go onto the next section on "Head", however, if in doubt at all measure the flow.

Streamflow is difficult to eyeball. 2. The minimum flow in the stream is about equal to

or is slightly more than the flow needed to produce maximum power. You should

measure the lowest flow, then estimate the minimum flow that can be expected in the

stream: this is explained later. 3. The minimum flow in the stream is less than the flow

needed to produce maximum power, and water will have to be stored for part of theyear (water storage is discussed in Section 1.6.3), or a diesel generator will have to be

used when the flow is low. In this case, you need to know the low and average flows.

You should measure the lowest flow you can and also the average flow, several times.

If the stream dries in the summer or winter, measure the lowest flow about one month

before it normally dries. Measure the flow when it is low and/or average, according to

the three guidelines above. Make several measurements on different days.

1.5........ INSTALLATIONS(Back)

This is the time to decide on a preliminary arrangement for your hydro project: The

locations of the intake, dam, pipeline and powerhouse: and the type of turbine needed.If possible, get a map of the area from a government office, a local logging company or

a forester with the Ministry of Forests maps, and where to get them are discussed in

Supplement 2.1 at the end of Chapter 3). Draw on the map the intake, dam, pipeline,

powerhouse, and transmission line. This will help you define the layout and help you

describe the project to someone else, such as a small hydro owner, a bank manager, a

person in the Water Rights Branch office:

To help you decide on a layout, the following considerations will be covered in this

section:
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(a) run-of-river versus storage projects;

(b) typical project layouts;

(c) project structures ie. dam, weir, intake, canal, pipeline, powerhouse, tailrace,-

(d) to suitable turbines (Cross-flow, Francis and Pelton turbines) for love, medium and

high head projects;

(e) existing dams and;

(f) transmission lines.

1.5.1 Run-of-River versus Storage Projects

A run-of-river project is built to use some or most of the flow in a stream depending

upon the flow throughout the year. No attempt is made to store water for the dry

periods. A run-of-river project would not normally have a dam, other than an intake

weir, which is a very low structure at the intake. The intake weir keeps the water in

the stream high enough to fill the pipe at all times.

A storage project on the other hand, has a dam, which creates a water storage

reservoir to maintain flow in the stream during low flow periods. The intake to the

pipeline might be part of the dam or separate from it, depending on the location of the

pipeline.

1.5.2 Project Layouts

The layouts shown in Figure 1.5 are typical of most projects that would be built in

B.C.

Layout #1 is the simplest, with a weir or low dam across the stream, an intake to the

pipeline, the pipeline, powerhouse and tailrace channel (each structure is described in

more detail in Section 1.5.3). The weir forms a pond to ensure that there is always

water above the pipe at the intake; the pipeline carries the water, under pressure, to

the turbine in the powerhouse; the tailrace channel carries the water from the turbine

back into the stream, or into a lake or the sea.

Layout #2 illustrates a possible cost-saving arrangement, whereby a canal or low-

pressure pipeline is built to contour around a hillside, and a shorter high-pressure

pipeline, called a penstock, is used.

Layout #3 shows a pipeline intake incorporated in a storage dam.

Layout #4 shows a situation where there is a lake suitable for a storage reservoir some

way up the stream. A dam can be built at the lake to store water, which can be

released down the stream during dry periods.


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Layout #5 and Layout #6 show the layout of a low head plant where there is less than

10 m gross head. Notice that there is no pipeline or dam. Layout #5 shows the weir,

intake and powerhouse combined into one structure. Layout #6 shows a power canal

between the intake and powerhouse.

Many aspects of a low head plant are different from those of a higher head plant (head

greater than 20 m): flows are higher, the turbine is larger, no pipeline is used. For

these reasons low head plants are discussed separately in Chapter 8.

1.5.3 Structures

The structures of a hydro project are described in detail in this section. Guidelines for

selecting sites for these structures are given in Chapter 2, Section 2.6. Suggestions are

given below for estimating dimensions for some of the structures. This will enable you,

in Section 1.8.1, to estimate the cost of your project.

Storage Dam

A storage dam, normally 3 m to 10 m high and constructed of earth or rock, should be

designed by an engineer.

There are many different designs for earth and rock dams. A typical earth-fill dam, as

shown in Figure 1.6, has a central section constructed of low permeable material

supported on either side by higher permeable material. The material has to be

carefully compacted in thin layers as it is built.

The pipe through the dam could continue to the turbine, or could discharge into the

stream or a canal at the downstream side of the dam. There would be a valve at the

upstream end of the pipe.

A spillway would be built into the dam to allow high flows to pass without overtopping

the dam. The crest of the spillway would be lower than the top of the dam.

Intake Weir

Normally you would need to build a low weir (1 m to 2 m high) across the stream at

the intake to the pipeline, to form a headpond (see Figure 1.6). This headpond would:

(a) ensure a high enough water level to keep water always above the top of the pipe.

(b) allow some of the sediment in the stream to settle out before entering the sediment

trap,

(c) allow an ice sheet to form, giving some protection against water freezing in the

pipeline, and

(d) provide pondage (water storage) to compensate for one or two-day water


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shortages.

Water would flow over the weir most of the time.

While there are many ways to build a weir, concrete, rock-filled gabion and rockfilled

timber-crib structures are the most common for small hydro projects (see Figure 1.6).

If the weir is built across a narrow part of the stream and founded on bedrock, a

concrete structure would probably be the most economical. In other cases a concrete

structure would probably be the most expensive, but it would also last the longest

without maintenance.

A gabion is a wire-mesh box filled with rock. Assuming there is a good supply of rock

at the site, only the wire-mesh need be bought and transported to the site. Gabions are

not waterproof, so an impervious polyethylene membrane or asphalt sheeting wouldbe laid on the upstream side. Fill would be placed on the upstream side to protect the

membrane. A reinforced concrete cap should be placed on the top of the gabions to

protect them from the water and debris passing over the weir.

A rock-filled timber-crib dam is often the least costly weir to build, especially if rock

is,available at the site and timber can be cut nearby.- Timber or logs are placed in

alternate directions and spiked where they cross (see Figure 1.6). The bottom logs

should be anchored to the foundations, and the space between the logs should be filled

with rock. Wooden sheathing is attached to the upstream face and the crest, and often

sheathing is also placed on the downstream face. Low permeability fill should be

placed upstream to reduce seepage through the dam and foundations.

Water in the headpond must be kept at a certain height (called submergence) above

the top of the pipe, to prevent air entering the pipe. Values of submergence are given

below:

Pipe Diameter Submergence

less than 600 mm = 1.0 m

600 - 1200 mm = 1.5 m

(Pipe diameter is discussed in detail in the "Pipeline" section, which follows.)

The crest of the weir should be above the top of the pipe by an amount equal to 0.5 m

plus submergence.

Intake

The intake to the pipeline can be a separate structure, part of the intake weir, or part

of the storage dam. There are many types of intake. The sketch in Figure 1.6 shows the

components of a typical intake.


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To prevent sediment from flowing into the turbine, a sediment trap can be built

upstream of the intake structure or within the structure; or immediately downstream,

as a separate self-flushing tank built into the pipe.

A trashrack prevents floating debris from entering the pipe. Trashracks must be

cleaned regularly.

Stop-logs or a valve should be provided to shut off the flow from the pipeline during

maintenance or repair of the pipe, or closure of the turbine during cold weather. An

air vent should be placed just downstream of the valve to prevent the pipeline

collapsing when it is emptied with the valve closed.

The top of the intake should be at least 0.5 m below the top of the weir.

Pipeline

To help you determine the preliminary arrangement and cost estimate of your project,

you also need to decide on pipe diameter, pipe material, above-ground or underground

pipe location, pipe support and anchore blocks.

You need to know the diameter of the pipeline to estimate its cost in Section 1.8.1. The

diameter can be read from the graph in Figure 1.7, by using your value of Qmin (from

Section 1.4.1, or from Table 1.3) on the horizontal axis, then reading the diameter on

the vertical axis.

Example: Your Values

pipe flow =Qmin.....................................200 L/s ...................................L/s

or 0.20 m3/s ....................................M3/s

Pipe Diameter D................................... 410 mm .........................mm

Write your value of pipe diameter in Table 1.3 for later reference.

Steel, cast iron, aluminum, polyethylene and PVC are materials used for small hydro

pipelines and penstocks. Generally, for the higher head sites in B.C. (above 20 m head)

polyethylene or PVC are used. When the head is greater than about 60 m, use of steel

at the lower end (higher head) of the pipeline is more economical.

PVC pipe should be buried for protection from the sun's ultraviolet rays and

polyethylene and cast iron pipes should be buried for potection against damage from

falling trees or rocks, or from logging machinery. If air temperatures normally stay

below -5C for more than five days at a time, the pipeline should be buried or insulated.

Supports must be provided for rigid pipes such as steel, cast iron, or aluminum, but

the more flexible polyethylene can be laid directly on the ground or on woodensupports. Anchor blocks should be placed around the bends of all types of pipes. A


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thrust block should be built at the lower end of the pipeline, just upstream of the

powerhouse.

Powerhouse

The size of the powerhouse is determined by the type and size of the turbine installed.

Figure 1.6 shows typical layouts for Pelton and Francis turbines. A low head plant

(less than 10 m head) looks quite different: See Chapter 5 for details.

The substructure -- which consists of the pedestal of the turbine and generator, the

draft-tube or discharge pit, and the floor slab - should be made of concrete. The

superstructure -which is above the floor and protects the machinery and electrical

controls from rain, heat, cold and vandalism -- can be made of wood frame, metal

frame, concrete block, log or self supporting metal panels. Make sure that the

superstructure allows the turbine and generator to be installed and removed forrepair.

Tailrace

The tailrace is a channel which leads the water from the turbine back into the stream,

a lake or the sea. It should prevent the water from damaging any structure or the

landscape.

1.5.4 Low, Medium and High Head

Low, medium and high head are terms used to indicate the most suitable type ofturbine for the project. The various types of turbines listed in the table below are

described in Section 4, "Turbines".

- Low Head up to 10 m Use: Cross-flow, axial-flow or propeller turbine

- Medium Head 10 m to 200 m Use: Cross-flow, Francis, Pelton or Turgo turbine

- High Head 200 m to 1000 m Use: Pelton, Turgo-impulse or Francis turbine

1.5.5 Existing Dams

If there is already a dam on a stream nearby, you should consider using it. First, find

out who owns it, then try to assess what repairs would have to be done if you were to

use it as an intake dam or a small storage dam. Could you incorporate in the dam an

intake for a pipeline? You should have an engineer check the dam before further

developing your plans for its use. You should also check with Water Management

Branch as a changed use could require the dam to be upgraded.

1.5.6 Transmission Line

If your load (i.e. house, bunkhouse, sawmill, etc.) is more than 100 m from yourpowerhouse, you will need a transmission line, and probably step-up and step-down


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transformers. Transmission lines are expensive ($17,000/km or more) so always plan

to put the powerhouse as close as possible to your load; however, they are less

expensive than pipelines so a trade off must be made.

1.6....... AVAILABLE POWER AND ENERGY (Back)

Now that you have measured, or estimated, the lowest expected flow (Qmin) and gross

head (Hg), you can calculate the power and energy available from the stream. To

calculate power, use the nomograph in Figure 1.3, or the power Equation 1-3, as

explained in Section 1.6.1. The calculation of energy is explained in Section 1.6.4.

1.6.1 Firm Power

Firm Power is the power that is always available from the stream, even at times of

lowest flow and lowest head. To calculate firm power you use the lowest expected flowin the stream (Qmin) and the gross head (Hg). In the case of a low head plant (less

than about 10 m) in which the forebay level varies, the gross head should be measured

to the minimum forebay level.

Using these new symbols for Q and H, the power equation (1-2)

becomes: FIRM POWER (Pfirm) = Qmin x Hg x 5.9 kW (1-3)

Remember, in this equation, the overall plant efficiency is assumed to be 60 percent

because of head loss in the pipeline, and turbine and generator efficiencies. The

nomograph in Figure 1.3 was drawn from this equation.

With the values of Qmin and Hg that you have written into Table 1.3, use the

nomograph in Figure 1.3 to calculate the firm power Pfirm.

Example:

Example Your Values

On the nomograph enter:

Qmin 200 1/s 1/8

Hg 30 m m

From the nomograph:

Pfirm 35 kW kW

Write your Pfirm value - the firm power available from the stream into Table 1.3.

1.6.2 Design Capacity of Hydro Plant
http://www.smallhydropower.com/manual3.htm#chap1%23chap1http://www.smallhydropower.com/manual3.htm#chap1%23chap1


15/34

The design capacity (or installed capacity) of your hydro plant is the maximum power

it can produce. For this stage in the planning process, assume that the design capacity

is made equal to the maximum load, using some load management, as discussed in

section 1.2.2. Also, assume that the plant can produce maximum output -equal to the

maximum controlled load -- when the flow in the stream is at its lowest. This means

that the plant will be able to produce all the power you need, even during dry periods.

These assumptions are summarized:

Design capacity of plant (kW) = Maximum load (kW) = Firm power (kW)

This is a simplifying assumption that is satisfactory for the calculations in Chapter 1, a

more detailed analysis is made in later chapters.

1.6.3 Storage Reservoir

If your hydro plant cannot produce enough power to meet your peak load when the

streamflow is low, you can:

(a) build a dam and create a storage reservoir, or

(b) Use a diesel generator or other source of power during low flow periods.

The stream might dry up completely in the summer or in the winter after several

weeks of very cold weather. Even with a storage reservoir or an alternative source ofpower for these short no-flow periods, a hydro project might still be economic.

Decide if you want to build a storage dam or use an alternative source of power. If you

already have a diesel generator, you might choose to use that. If there is a lake

upstream of your planned pipeline intake, you might choose to build a small dam at

the outlet of the lake to control storage.

You do not have enough information yet to calculate the volume of storage you

require, or the height of the dam. How to calculate these is described in Chapter 3.

Until then, if you plan to build a dam, follow the guidelines in Section 1.8.1 for

including an allowance for the cost of the dam.

1.6.4 Energy

Next, estimate the average annual energy that you will use from your hydro plant. You

will need this in Section 1.8.2 to estimate your hydro energy cost (cents/kW.h). By

comparing this cost with the cost of alternative sources of energy, such as a diesel

generator or energy from a B.C. Hydro power line, you can decide if you wish to build

the hydro project.

The amount of energy that you will use from your hydro plant will depend on:


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(a) the design capacity of the plant, compared to the flow and head available in the

stream, and

(b) the variations in your load (discussed in Section 1.2.1).

For each plant and stream, there is a specific set of conditions which has to be known

before you can calculate accurately the average annual energy output.

At this stage you do not have enough data, and simplifications must be made.

If you wanted to generate constant power equal to your maximum load (assuming

some degree of load management), the annual energy output would be:

B (annual) = Pdesign x 8760 kW.h (1-4)

Where:

E (annual) = Annual energy output (kW.h).

Pdesign = Firm power (kW) calculated in Section 1.6.1. 8760 = Number of hours in a

year.

However, your load will not be constant (as discussed in Section 1.2.1) and the design

capacity of the plant (Pdesign) would probably be larger than your maximum load, to

include the possibility of increased loads in the future. You will also have to shut down

the plant for maintenance. For these reasons, your actual annual energy output will beless than indicated by Equation (1-4). To account for this, a Plant Factor (or Capacity

Factor) is used:

Plant Factor (PF) Average power generated during year Plant design capacity

(Pdesign)

The average annual energy output would then be:

E (annual) = Pdesign x PF x 8760 kWh (1-5)

Plant factors describe the way in which a plant operates over a period of time, say, for

several years.

For these preliminary estimates of average annual energy, use a plant factor of 80

percent. (A plant factor of 80 percent applies to a system with automatic load

management. If you do not intend to use automatic load management, use a plant

factor of 50 percent.)

Average annual energy is:

E (annual) = Pdesign x 0.8 x 8760 (1-6)


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= Pdesign x 7000 kw.h

Example:

In the previous examples in Section 1.6.1 we calculated the Firm Power output of a

stream to be 35 kW. Assume that the plant is designed to produce maximum power

equal to this Firm Power from the stream.

Using Equation (1-6), the average annual energy used is:

E (annual) = 35 x 7000 kW.h

= 245,000 kW.h

1.7....... ADVISORS (Back)

Turbine manufacturers, pipe suppliers, contractors and electricians will give you free

advice. owners of small hydro plants, particularly those who have built their own, will

usually be pleased to tell you about their experiences and offer advice.

1.7.1 Engineers

You can hire an engineer to do part or all of the design of the project. An engineer can

(a) advise on specific problems such as, safety of the existing dam you might want to

use; foundations for a dam, pipeline supports or powerhouse; type of electrical ormechanical equipment;

(b) design certain structures such as a dam, pipeline supports, an electrical load

control panel, or a turbine;

(c) make a preliminary study to confirm the feasibility of the project;

(d) prepare a feasibility report for a bank or investor from whom you want to borrow

money; or

(e) design and supervise the construction of the project.

Guidelines on the cost of these services are given in Section 1.8.1, "Engineering Costs".

Before you hire an engineer, contractor or any other professional person, ask for an

estimate of the cost of services and expenses to be paid. Ask him to write down exactly

what he will do and how long it will take. Make sure you understand what he said he

would do, and that this is what you want. When he's finished the job and you want

him to do more, or he suggests doing more, again, ask for an estimate on the additional

work. In that way you are in control of your expenses and you will avoid unpleasant

surprises when you receive his bill.


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The decision to hire an engineer is yours, but there are typical situations under which

you are advised to hire an engineer:

(a) Dam Design: If you need to build a storage dam, or if your intake dam is more than

1.5 metres high, an engineer should check the design and the foundations.

(b) Existing Dam: If you plan to use an existing dam to store water, an engineer should

check the safety of the dam.

(c) Pipeline: If the head is greater than 30 m; if the length is longer than 300 m; or if

the diameter is larger than 0.5 m an engineer should review your design for

waterhammer, pipe strength, pipe supports and anchors. These limits are abribtrary

and may not apply to all sites.

(d) Excavations: If you have to excavate into a steep or unstable looking side slope foran access road, pipeline or the powerhouse, an engineer should first check the stability

of the slope.

(e) Safety If there are residences downstream of any part of the project and you will be

changing the natural stream channel or leading water out of the natural channel in a

canal or pipeline), an engineer should check the safety of the project.

1.8.......PROJECT COSTS (Back)

1.8.1 Capital Costs

Your project cost estimates will be very preliminary at this stage. You can use the cost

curves in Figure 1-7 to 1-12 to find the cost of most of the components of your project.

You might want to buy used equipment or materials, such as:

- turbine

- pump - to be operated in reverse as a turbine

- generator

- other electrical equipment and wiring

- steel or plastic pipe

You can save 50 percent or more on the cost of new items. Ask turbine manufacturers

if they have a used turbine or generator that would suit your project. Scrapyards and

used equipment dealers are places to look for pumps, valves, electrical equipment,

wire and pipe. Used equipment and materials are advertised in newspapers and trade

journals and magazines.

No costs for used equipment are given in this manual -- you will have to estimate costs

based on your own enquiries. Beware, there are no guarantees on used equipment or

materials, so make sure you know what to look for to check that the equipment or

materials are in good condition.


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When you have estimated the cost of each component, write it into the Summary of

Project Costs, near the end of this section.

Site Preparation

Timber and brush will probably have to be cleared at the site of the intake, along the

pipeline, at the powerhouse and along the transmission line. The storage reservoir, if

you need one will have to be cleared before you flood the area. A cat track or access

road might have to be built to get construction materials and equipment to the intake,

pipeline or powerhouse.

The cost of the work depends on the conditions at the site, therefore no cost curves are

given to help you make an estimate. You could ask a local contractor, logger or cat

owner for an approximate price.

Remember to include a cost -- even if it is only a guess -- for site preparation in your

project cost estimate.

Storage Dam

You decided in Section 1.6.3 whether or not you needed a storage dam. At this stage

you cannot make a reliable estimate of the cost of the dam. However, if you need to

build a dam, include a cost for it in the Summary of Project Costs to remind yourselt

that a dam could be a major part of the project cost. use the larger of the following

alternative costs:

(a) twice the cost of the intake weir (to be estimated next), or

(b) ten percent of the total civil, mechanical and electrical costs (to be calculated in the

Summary of Project Costs at the end of this section).

Intake weir

The intake weir could be built of concrete, rock gabions or rock-filled timber crib. A

concrete dam would probably be the most expensive, a rock-filled dam the least

expensive. Cost curves for concrete and gabion weirs only have been given in Figure

1.8. If you plan to build a timber-crib dam, you can make your own cost estimate oruse the cost curve for the gabion weir, knowing that you are probably over estimating

the cost of a timber-crib weir.

The curves in Figure 1.8 are for work done by a building contractor who pays union

wages. Costs can be as low as 60 percent of the costs shown in Figure 1.8 if you do not

hire a contractor and if the following conditions apply:

(a) you do most of the work yourself or pay wages at $12 per hour. and

(b) for the concrete dam you mix concrete at the site, or


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(c) for the gabion dam you do not have to pay for delivery of rocks for the gabions

because there are rocks close to the site.

To find the cost of the weir using Figure 1.8:

(a) decide on the type of weir you will build,

(b) decide on the height of the weir

(c) select the height on the vertical axis, then read off the cost per metre of weir on the

horizontal axis,

(d) estimate the length of weir, and

(e) calculate the cost using the formula cost of weir = cost/m x length (m).

Example:

Concrete weir 1.5 m high, 6 m long, built by contractor.

Using Figure 1-8:

Example Your Values

Weir height ..................................... 1.5m .....................................................m

Weir Length .....................................6.0m ......................................................m

Cost per length of weir (b) .. 210 $/m ..................................................$/M

Cost of weir (a x b)...........................1260 $ .......................................................$

Pipeline Intake

In Figure 1.9 cost curves are shown for a free-standing intake for a gabion or rock-

filled timber weir, and for an intake for a concrete weir where the backwall of the

intake would be part of the concrete dam.

To find the cost of the intake using Figure 1.9

(a) select the pipeline diameter,

(b) find the submergence required for this pipe diameter, using the bottom graph,

(c) estimate the actual height of the intake (the headpond behind the intake weir might

be deeper than the minimum height required in Item 2 above),

(d) find the cost of the intake for the correct pipeline diameter, using the top graph,


21/34

and

(e) add the cost of the trashrack from the middle graph.

Example:

Pipe diameter (Section 1.5.3. "Pipeline") D = 410 mm

Submergence required (bottom graph Figure 1.9) = 1.0 m

Height of intake = height of weir (1.5 m) + 0.5 m = 2.0 m

Cost of intake (using 500 mm pipe diameter on Figure 1.9) = $670

Cost of trashrack for 400 mm pipe (middle graph figure 1.9) $180

Total Cost of Intake $850

Pipeline

Before you can calculate the cost of the pipeline, you must first make a sketch of the

pipeline route (as shown in Sketch (A) in Figure 1.10) and mark a few ground

elevations and lengths along the pipeline to define the profile. For example, EL. 10 m,

EL. 20 m, EL. 30 m; and Ll, L2, L3' This will enable you to estimate the head on

various sections of the pipeline, (as shown in Sketch (B)) and to choose the correct cost

for each section: this applies to polyethylene plastic pipes only.

In the table on Figure 1.10, Column #1 shows a Pipe Classification which corres nds to

a range of Gross Heads (or pressure heads) in Column #2. Each classification of pipe

can withstand a pressure head equal to the maximum in the range in Column #2, for

example, "A" pipe can withstand a gross head up to 31.6 m, and "B" pipe a gross head

of 42.2 m. This classification is for polyethylene pipe only; steel pipe is strong enough

to withstand a gross head in excess of 150 m.

For costing polyethylene pipe, mark off the maximum gross head in each classification

on your sketch of the pipeline starting from the intake, as in Sketch (B), Figure 1.10.

Then measure the length of each classification of pipe, for example LA, LB, LC in

Sketch (B).

For each classification, read from the table on Figure 1.10 the cost per metre of pipe

under the appropriate pipe diameter; multiply that unit cost by the length for that

classification to give the cost of that section of pipe.

Example:

Pipe diameter - 410 mm inside diameter. Assume a nominal outside diameter of 45U

mm.


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Draw a table as shown below. The lengths LA, LB etc. are taken from your sketch,

similar to Figure 1.10, Sketch (B). The unit costs of pipe per metre are taken from the

table on Figure 1.10. We will assume a 500 mm pipe in this example, but you could

interpolate the cost for a 450 mm diameter pipe between the costs for pipes of 315 mm

and 500 im-n.

Pipe Length Unit Cost Cost of Section

Classification m $/m $

A LA = 50 155 7750

B LB = 10 205 2050

C LC = 20 265 5300

D LD = 13 324 4212

E LE = 13 518 6734

F LF = 10 518 5180

Total Cost of Pipeline $31,226

Note that the unit costs of 500 mm diameter pipe in Classes E and F are below the

heavy line in the table, indicating that they are steel pipe. A polyethylene pipe of thatdiameter cannot withstand a gross head greater than 70.3 m (classification D).

Add the cost of a valve, from the table on Figure 1.10, to get the total cost of the

pipeline.

Powerhouse

Figure 1.11 shows cost curves for the powerhouse sub-structure (concrete foundations

and floor) and superstructure (wood or prefabricated metal).

For the sub-structure cost you need the rated output of your hydro plant in kW, which

you should already have estimated. Use the top graph on Figure 1.11 to find the sub-

structure cost.

The superstructure floor area depends on the physical dimensions of the turbine and

generator. The size is related to the penstock diameter. Use the bottom graph on

Figure 1.11 to find the cost of the superstructure for the penstock size and type of

turbine you have selected.

Add the costs of the sub-structure and superstructure to get the total powerhouse cost.


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Turbine, Generator and Electrical Equipment

Use Figure 1.12 to estimate the cost of the turbine, generator and electrical equipment

in the powerhouse. You need to know the gross head (from Section 1.4.2) and the

energy output hydro plant in kW. To find the cost of the equipment, find the head on

the vertical axis, draw a line horizontally to intersect the diagonal line with the correct

range of plant output (you can interpolate between these lines), then draw a vertical

line down to the horizontal axis. Read the cost (in $/kW) of the equipment and

multiply by the plant output in kW.

The cost lines on Figure 1.12 were derived from manufacturers prices and show

average costs. They should be used only for initial estimates, since the prices you

actually pay for the turbine, generator and other electrical equipment could be as

much as 40 percent less than the costs given on Figure 1.12. You will generally get the

quality you pay for: low-priced turbines will probably be made of cheaper materialsand will probably require more repair than higher-priced turbines.

A very small turbine-generator unit (1.0 - 1.5 kw) with batteries and a battery-charger

might be suitable for lighting and a few appliances in a small, well-insulated house or

summer cabin. The cost of turbine, generator, batteries, and inverter would be about

1.0 kW $ 9000

1.5 kW $13000

Remember, if you will be converting from existing oil or propane heating to electricheating, there will be additional costs for electric heaters and wiring at your house,

lodge, camp, or mill. These additional costs are not covered in this manual.

Transmission Lines and Cables

Use the table below to estimate the cost of transmission lines or cables running from

the hydro plant to the load. Refer to Chapter 4 for a discussion of voltages and

different types and sizes of cable you should use.

Wood Pole Transmission Line

3-phase, 2.4 kV, up to 250 kW: $17000/km

High Voltage Buried Cable

single-phase, up to 85 kW: $15000/km

Tailrace Channel

The tailrace channel is usually a minor cost item, however, a cost figure should be

included in the estimate. A cost curve cannot be prepared for the tailrace channelbecause the channel dimensions depend entirely on the site. Make your own estimate


24/34

for this item or ask for an estimate from the person who advised you on the clearing

and access costs.

Contingencies

Contingencies are unexpected costs.

The cost curves in Figure 1.8 to 1.12 were drawn using cost estimates from

manufacturers, suppliers and contractors, and using costs of projects recently built.

However, the cost of your project will probably be more than you have estimated so

far: that's the way things usually turn out. Some reasons for this:

1. The project you build might be more complicated than the one you have planned.

2. The dimensions of the project you build might be larger than you have estimated.

3. The cost curves do not include every possible expense.

4. Unexpected problems will probably arise during construction.

5. Add more if the project has accessability problems.

To avoid surprises, be conservative. Add a contingency item to your cost estimate, as

follows:

1. Add 15 percent if you think your project will be easy to build, and you think youhave included everything.

2. Add 25 percent if you think your project might be more complicated than most, or if

you think you might have underestimated some of the dimensions such as, length of

penstock or transmission line.

Engineering Costs

You have probably decided whether or not you will hire an engineer. This section

suggests costs to expect for engineering services.

Even if you want to do all the planning yourself, you should still provide for the cost of

expert advice you might need unexpectedly.

If you do hire an engineer, here are some guidelines to help you estimate the costs. For

advice on specific problems, or the design of certain structures, engineers normally

charge hourly or daily rates for their services:

$30 to $70 per hour; $200 to $500 per day.

For a visit to the site, an engineer would expect to be paid, probably at a reduced rate,while he was travelling, and he would want to be paid for reasonable expenses.


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Generally, a self-employed engineer will charge less than a firm of engineers which has

to cover higher overheads.

If you have to borrow money to build the project, the banks, or other investor, may

ask for a feasibility study report to show:

(a) the availability of a site for your project,

(b) the availability of sufficient flow and head to produce the power and energy you

need,

(c) an estimate of the costs of the project, and

(d) a simple financial analysis showing loan repayments and other facts the bank or

investor might require.

For a feasibility study and report, expect to pay between a minimum of $2000 (that

would be a nominal fee) and, $7000 to $15000 for a project of 50 kW to 250 kW.

For a feasibility study report, and the complete design and construction supervision of

a project, expect to pay 5 to 15 percent of the project cost, or a minimum of $8000.

Remember, before you hire an engineer or other expert, ask for an estimate of the cost

and a letter detailing exactly what the engineer will do for the money.

Summary of Project Costs

Make a list of all the costs that apply to your project.

Example Costs Your Project Costs

Clearing and Access $1000 ......................$

Storage Dam $0 ......................$

Intake $1300 .....................$

Pipeline $31900 .....................$

Turbine, Generator, Electrical Equipment $45500 .....................$

Powerhouse $10700 .....................$

Transmission Line $8000 ....................$

TOTAL COST OFSTRUCTURES AND EQUIPMENT (a) $98400 ....................$


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Engineering $7000 ....................$

Contingencies (15% of (a)) $15000 ....................$

TOTAL PROJECT COST $120,400 ....................$

Cost per kW

To check the cost of your project, compare its "Cost per kW" with other plants. To get

the cost in $/kW, divide the total project cost by the design capacity of the plant (from

Section 1.6.2).

Example Your Figures

Total Project Cost (from Summary of Project Costs) $120,400 ..................................$

Design Capacity (from Section 1.6.2) 35 kW ..............................kW

Cost per kW...............................3,440 $/kW ...........................$/kW

The cost per kW should be within the range of $2000 to $5000 per kW.

If your figure is around $2000 per kW you have a good project. If the figure is around

$5000 per kW, you still might have a project that is cheaper than an alternative power

source, such as diesel. You will know this when you have calculated the annual cost of

your plant in Section 1.8.2.

Degree of Confidence in Project Cost Estimate

Only an approximation of the actual project cost can be expected at this stage in the

planning process, when the structures have yet to be designed and the sites have yet to

be carefully examined. Nevertheless, the actual project cost will probably be within 25

percent of your estimate.

1.8.2 Annual Costs

You should be aware of the annual cost of energy, including loan payments and

maintenance and repair costs, of your hydro project. You might want to compare that

cost with the cost of energy from a diesel generator or from a nearby transmission line.

Loan Payments

Decide how much you will have to borrow to cover the total project cost, then calculate

your annual payments (capital and interest) using a Capital Cost Recovery Factor

(CRF) from Table 1.2.

Example:


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Assume you want to repay a loan in 10 years, and the interest rate is 10 percent.

Example Your Values

- Total Project Cost $120400 $..............................

- Equity Available for Project $ 30400 $..............................

- Loan Required (a) $ 90000 $..............................

From Table 1.2:

For: n 10 years ........................years

I =10% ...............................%

Find: CRF 0.163 .................................

Annual Loan Payment:

(CRF) x (a) 0.163 x 90000 ........................X......................

=....... $14,670 $...............................................

Maintenance and Repair Costs

Maintenance and repair costs include maintaining the intake, dam, pipeline,

powerhouse and the mechanical and electrical equipment. The maintenance work that

should be done is discussed in Chapter 3. However, for this initial estimate of annual

costs, use 2% of the Total Project Cost, or $2000 minimum annual maintenance cost.

Total Annual Costs

Add the annual loan payments and the annual maintenance and repair costs to get the

total annual cost. Divide this by the estimated annual energy output (from Section

1.6.4) to get the cost per kW.h.

Example:

Example Your Values

- Annual Loan Payment $14,670 ...........$

- Annual Maintenance & Repair Costs $ 2400 ...........$

-Total Annual Costs (a) $17,070 ...........$Annual Energy Output (from section 1.6.4) (b)

245000 kW.h kW.h


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- Cost per kW.h = (a) x 100/(b) = 7.0cents/kW.h cents/kW.h

1.9 ..........Project Worth (Back)

1.10 ..........Continued Planning (Back)

1.11 ..........Project Data Summary (Back)

SUPPLEMENT / MEASURING HEAD AND STREAMFLOW / PRELIMINARY

CHAPTER #2 - SITE EXPLORATION AND STREAMFLOW DATA


2.2 ..........Topographic Maps

2.3 ..........Streamflow Data

2.4 ..........Streamflow Measurement

2.5 ..........Water Quality

2.6 ..........Site Selection for Project Structure

2.7 ..........Head Measurement

2.8 ..........Pipeline Length

2.9 ..........Project Site Topography

2.10 ..........Environmental Aspects

SUPPLEMENT 2.1:

Maps, Air Photos, Streamflow and Climate Data

SUPPLEMENT 2.2:

Installing a Staff Gauge and Weir to Measure Streamflow

CHAPTER #3 - ASSESSMENT OF THE FEASIBILITY OF YOUR HYDRO

MANUAL


3.2 ..........Power and Energy Requirements
http://www.smallhydropower.com/manual3.htm#chap1%23chap1http://www.smallhydropower.com/manual3.htm#chap1%23chap1http://www.smallhydropower.com/manual3.htm#chap1%23chap1http://www.smallhydropower.com/manual3.htm#chap1%23chap1http://www.smallhydropower.com/manual3.htm#chap1%23chap1http://www.smallhydropower.com/manual3.htm#chap1%23chap1


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3.3 ..........Load Planning and Management

3.4 ..........Power and Energy Availability

3.5 ..........Small Hydro Plant Sizing

3.6 ..........Preliminary Arrangement of Structures and Selection of Equipment

3.7 ..........Project Costs

3.8 ..........Preliminary Assessment of Feasibility

3.9 ..........Continued Planning

SUPPLEMENT 3.1:

Flow Duration Curves

SUPPLEMENT 3.2

Calculating Reservoir Storage

SUPPLEMENT 3.3

Information from Turbine-Generator Manufacturers and Suppliers

CHAPTER #4 - CIVIL WORKS AND EQUIPMENT

Introduction

4.1 ..........Dams

4.2 ..........Intake Structures

4.3 ..........Diversions

4.4 ..........Maintenance of Dams and Intakes

4.5 ..........Factors affecting costs and construction

4.6 ..........Penstock Design

4.7 ..........Characteristics of Pipes

4.8 ..........Plastic Penstocks

4.9 ..........Steel Penstocks


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4.10 ..........Forces and Trust Blocking

4.11 ..........Installation of Penstocks

4.12 ..........Water Hammer

4.13 ..........Valves

4.14 ..........Canals, Flumes and Lines Channels

4.15 ..........Turbines

4.16 ..........Water Control to Turbine

4.17 ..........Mechanical Governors

4.18 ..........Electronic Load Control Governors

4.19 ..........Tailwater

4.20 ..........Draft Tubes

4.21 ..........Pumps as Turbines

4.22 ..........Generators

4.23 ..........Mechanical Power Transmission

4.24 ..........Induction Generators

4.25 ..........Synchronizing

4.26 ..........Power Factor

4.27 ..........Electrical Transmission

4.28 ..........Transformers

4.29 ..........Single and Three Phase Systems

4.30 ..........Automatic Emergency Shutdown

4.31 ..........Remote Alarms

4.32 ..........D.C. Systems

4.33 ..........Electrical Inspection and Codes


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8.2 ..........Water Wheels

8.3 ..........Modern Turbine Types

8.4 ..........Package Visits

8.5 ..........Variable Heads

CHAPTER #9 - COLD WEATHER CONSIDERATIONS

9.1 .......... Cause and Effect

9.2 ..........Climate

9.3 ..........Frost

9.4 ..........Cold Weather

9.5 ..........Ice

9.7 ..........The Dam or Diversion Structure

9.8 ..........Intake Structure

9.9 ..........Canal

9.10 ..........Penstocks

9.11 ..........Powerhouse

9.12 ..........Transmission Lines

9.13 ..........Access

9.14 ..........Conclusion



10.2 ..........Rationale for Utility Regulation

10.3 ..........Relevant Registration

10.4 ..........Regulatory Alternatives


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10.5 ..........Application Procedure

10.6 ..........Organizational Structure and Accounting Procedures

10.7 ..........Implications to Organizing and Operating as a Public Utility

*GLOSSARY*

A ..........Case Study Examples

B ..........Permit Applications and Agency Addresses

C ..........Small Hydro Suppliers and Contractors

D ..........Small Hydro Consultants

E ..........Small Hydro Computer Programs

F ..........Definitions

G ..........Sources of Financing

H ..........References

Ron Williams

[email protected]

usion



10.2 ..........Rationale for Utility Regulation

10.3 ..........Relevant Registration

10.4 ..........Regulatory Alternatives

10.5 ..........Application Procedure

10.6 ..........Organizational Structure and Accounting Procedures

10.7 ..........Implications to Organizing and Operating as a Public Utility

*GLOSSARY*

A ..........Case Study Examples
mailto:[email protected]:[email protected]


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B ..........Permit Applications and Agency Addresses

C ..........Small Hydro Suppliers and Contractors

D ..........Small Hydro Consultants

E ..........Small Hydro Computer Programs

F ..........Definitions

G ..........Sources of Financing

H ..........References

Ron Williams

[email protected]
mailto:[email protected]:[email protected]

Small Hydraulic Turbin Hanbook

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