minihydro water use application doc

8/8/2019 Minihydro Water Use Application Doc

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DIIAR. Priscila Escobar RojoMarco Mancini

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MINI-HYDRO WATER USE APPLICATION DOCUMENTS


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INDEX

MINI-HYDRO WATER USE APPLICATION DOCUMENTS........................................................................... 1

1. General description of the site. ............................................................................................... 1

1.1 Cartography..................................................................................................................... 1

1.1.1 Geological Study ......................................................................................................... 1

1.2 Gross and net head evaluation ....................................................................................... 11.2.1 Gross Head (HG).......................................................................................................... 21.2.2 Net Head (HN).............................................................................................................. 2

1.3 Stream flow evaluation .................................................................................................... 31.3.1 Stream flow records..................................................................................................... 41.3.2 Regionalized Stream flow............................................................................................ 41.3.3 The Flow duration curve (FDC) ................................................................................... 41.3.4 Residual or compensation flow [DMV]........................................................................ 51.3.5 Design Flood [QF] ........................................................................................................ 5

1.4 Plant capacity and energy output .................................................................................... 6

2. Technical description of the project ....................................................................................... 8

2.1 Diversion structure .......................................................................................................... 82.1.1 Weir ............................................................................................................................. 82.1.2 Residual flow device.................................................................................................. 102.1.3 Fish passageway....................................................................................................... 102.1.4 Spillway and energy and dissipation structures......................................................... 11

2.2 Conveyance structure ................................................................................................... 122.2.1 Intake......................................................................................................................... 122.2.2 Channels, canals or tunnels ...................................................................................... 132.2.3 Penstock.................................................................................................................... 132.2.4 Tailrace...................................................................................................................... 13

2.3 Power house ................................................................................................................. 142.3.1 Inlet gate or valve ...................................................................................................... 142.3.2 Turbine and control system ....................................................................................... 142.3.3 Generator and speed increaser (if needed)............................................................... 152.3.4 Protection systems and dc emergency supply .......................................................... 152.3.5 Substation.................................................................................................................. 16

3. Economic and financial analysis........................................................................................... 16

3.1 Investment and costs for installed capacity ................................................................... 163.1.1 Initial investment cost ................................................................................................ 163.1.2 Operation and maintenance cost............................................................................... 17

3.2 Benefits due to generation ............................................................................................ 17

3.2.1 Tariffs......................................................................................................................... 173.2.2 Incentives .................................................................................................................. 17

3.3 Cash flow forecast analysis ........................................................................................... 18

3.4 Methods of economic evaluation ................................................................................... 193.4.1 Time value of money ................................................................................................. 193.4.2 Payback method........................................................................................................ 193.4.3 Return on Investment method ................................................................................... 193.4.4 Net Present Value (NPV) method.............................................................................. 203.4.5 Benefit-Cost ratio[BCR]. ............................................................................................ 203.4.6 Internal Rate of Return method [IRR]........................................................................ 20

4. Environmental impact study. ................................................................................................. 21

4.1 Environmental general description of the site................................................................ 21

4.2 Impacts identification ..................................................................................................... 21


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4.2.1 Impacts during construction....................................................................................... 224.2.2 mpacts during operation ............................................................................................ 234.2.3 Impacts from the electric line..................................................................................... 23

4.3 Environmental impacts mitigation.................................................................................. 23

5. Grid connection characteristics. ........................................................................................... 23

6. Land properties information. ................................................................................................. 247. Supporting documents. .......................................................................................................... 24

7.1 Construction schedule ................................................................................................... 24

7.2 Developer information ................................................................................................... 25

8. Maps Drawings and Reports. ................................................................................................. 25

8.1 MAPS AND DRAWINGS: .................................................................................................... 258.1.1 Site Plan .................................................................................................................... 258.1.2 Topographic map of the Existing site conditions ....................................................... 258.1.3 Proposed site plan..................................................................................................... 258.1.4 Engineering and Detailed drawings........................................................................... 25

8.2 REPORTS:....................................................................................................................... 258.2.1 General Report. ......................................................................................................... 258.2.2 Hydrological and Hydraulic Study.............................................................................. 258.2.3 Geotechnical Report.................................................................................................. 258.2.4 Environmental Stydy.................................................................................................. 258.2.5 Economic and Financial Analysis .............................................................................. 25

9.REFERENCES:............................................................................................................................. 26


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MINI-HYDRO WATER USE APPLICATION DOCUMENTS.

In all countries of the European Union the development of mini hydro power plants requirea water use permission from the water authorities. The procedure for acquiring this permissionvaries from one country to another, but in general, applications should include a technical

description of the project to be analyzed by the authority in charge of the decision of approvingthe implementation of the plant.

This guide lines aims at giving to the water authorities comprehensive information andadvice to evaluate the technical items of the applications for mini-hydro developments and tochoose among different solutions for the same site.

The documents to include in the application file should give all the necessary details aboutthe project together with the technical and economic feasibility studies and the environmentimpact incidences and assessment. Hereafter the different items that should be studied anddescribed in a mini-hydro project are briefly discussed.

1. General description of the site.

In this chapter a general topographic and geomorphologic description of the site should bepresented together with an evaluation of the water resource availability and its generatingpotential, as well as a detailed description of the project, indicating the type of the proposedscheme (Run - off rive scheme; powerhouse located at the base of a dam, integrated powerhouse on a canal or in a water supply pipe), and the main characteristics of each one of thecomponents. Moreover any particular constraints of the site and /or environmental sensitivitiesshould be stated herein.

1.1 Cartography.

Application should include maps at scale 1:5000 - 1:25000 in which thediversion works, the conveyance device, the penstock, the powerhouse and the

tailrace should be precisely located. The geographic coordinates of the differentdevices should be also indicated.

1.1.1 GEOLOGICAL STUDY

Geological studies are needed to prevent regrettable consequences due toseepage under the weir, open channel slides or other geologic stability problems.

Geomorphologic studies should be carried out to demonstrate the stability ofthe ground along the weir foundation and its corresponding reservoir (whenpresent) and along the powerhouse foundation. In these analysis variation of waterlevel on the reservoirs wetted slopes should be considered.

Special attention should be paid to the channel design and a minimumgeomorphologic study of the terrain should be done to assure the stability of this

structure along the whole path, specially in high mountain schemes in which oftenthe surface zone is affected by different geomorphologic features such as soilcreep, rotational and planar soil slides and rock falls.

Geological study at this level of the project can be done by means ofPhotogeology at scales from 1:10 000 to 1:5 000 that allow the geologist to identifyrock types, determine geologic structures, and detect slope instability.

Results can be delivered as geomorphologic maps, at the same mentionedscales, in which all the surface formations affecting the proposed hydraulicstructures should be shown. Photographs of the zone after field surveying aredesirable

1.2 Gross and net head evaluation


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The vertical fall of the water is known as the head. It is essential forhydropower generation. In hydroelectric practice two types of head are defined:Gross head (HG) and Net head (HN).

1.2.1 GROSS HEAD (HG)

The gross head (HG) is the vertical distance that the water falls through in

giving up its potential energy. It is measured between the upper and lower watersurface levels at the intake and tailrace of the scheme. Sites where the gross headis less than 10 m are classified as low head, from 10m to 100m as mediumhead and above 100 m as high head. Except for very low heads, the gross headcan usually be considered as constant.

In high head projects the gross head can be measured directly from themaps. In low head schemes instead, field measurements of the gross head fordifferent flow-rates are usually necessary. These measurements should be carriedout using surveying topographical techniques. The precision required in themeasurement depend on the magnitude of the head. Smaller values of gross headrequire higher precision.

1.2.2 NET HEAD (HN)

The net head (HN) is the actual head seen by a turbine which is slightly lessthan the gross head due to losses developed along the path, from the diversion tothe tailrace, when transferring the water into and away from the machine. The nethead is obtained by subtracting to the gross head the sum of all these losses.

The losses that should be considered in the Net head estimation are of twotypes:

Friction losses (hf): Developed along the conveyance and the tailrace devicesdue mainly to the wall roughness. These losses can be calculated by means of oneof the well known empirical formulae such as the Manning equation:

43

2

f2Vh L

K R= 1.

where hf [m] is the total head loss due to friction, L [m] is the length of the waterpath form the intake to the end of the tailrace, K[m1/3/s] is the Strickler roughnesscoefficient which depends on the material of the pipe or channel and R [m] is thehydraulic radius, given by the ratio A/Pwith A [m2] wetted area and P [m] wettedperimeter.

Material StricklerK [m1/3/s]

Welded steel 70 - 90

Polyethylene (PE) 100 - 110

PVC 100 - 110

Asbestos cement 90 - 100

Ductile iron 60 - 70

Cast iron 70 - 75

Wood-stave (new) 75 - 80

Concrete (steel forms smooth finish) 65 - 70

Clean excavated earth channels 40 - 50

Stony or Cobbles 25 - 30

Gravelly 30 - 35


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Friction losses in pipes larger than 5 cm diameter with flow velocities under 3 m/scan be also obtained by the Hazen-Williams formulae :

.

..

1 85

f 1 165

L Vh 6 87

CD

=

2.

where hf [m] is the total head loss due to friction, L [m] is the length of the pipe,C[m1/3/s] is the Hazen-Williams coefficient which depends on the pipe material andD[m] is the pipe diameter.

Pipe Material Hazen Williams C

New uncoated steel 150

Riveted steel 110

Asbestos cement 140

Plastic pipes 135 - 140

New cast iron 130

Old cast iron 90 -105

Wood-stave (new) 120

Concrete (steel forms smooth finish) 140

Minor or local losses (h): In addition to friction losses, water flowing through aconveying system develop head losses due to geometric changes of channel orpipe at the inlet and outlet cross sections, at trash racks, bends, elbows, joints,valves and at sudden contractions or enlargements. These losses depend on the

velocity head and are expressed as the product of an experimental coefficient multiplied by the kinetic energy head:.

2Vh

2g = 3.

where h [m] is the local head loss, V [m/s] is the flow velocity, g [m/s2] gravityacceleration and is an experimental coefficient usually given by the devicemanufacturer.

1.3 Stream flow evaluationA site can be considered as topographically suitable for hydropower if there

is an adequate water supply. To estimate the water potential one needs to knowthe variation of the discharge throughout the year, though it is necessary to collectand analyze the available hydrologic data and to perform a Hydrological analysis.

In the best case, the interested stream is provided with gauging stationswhere flow time series data have been gathered regularly over several years.Unfortunately, most of the watercourses suitable for mini-hydro plants areungauged, thus, observations of discharge over a long period are not available andhydrological methods should be used to predict stream flow.

Hydrological analysis should produce the so called Flow Duration Curve orFDC which is the best way of expressing the variation in river flow over the year.

Moreover the hydrological study must address not only to water availability forproduction, but also to the definition of the residual flow for environmental or


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aesthetic purposes and to the frequency and severity of floods so as to designflood protection and control devices into the scheme.

1.3.1 STREAM FLOW RECORDS

When the interested river is gauged the evaluation of the generating potentialshould be done by means of the stream flow time series of at least 10 years. Alldata used to estimate the stream flow should come from certified agencies such asa national hydrological institute or any other world meteorological organisation.

Usually there is not a gauging station in the stretch of the river where thediversion structure of the mini-hydro development is proposed. Although, it ispossible to use records of other stretches of the same river or a similar nearbyriver. These flow records can be used to assess stream flow at the proposed site,as long as due allowance is made for the actual site location in relation to thegauging station. For the reconstitution of the time series for the referred stretch itshould be then necessary to specify the hydrological method used to put in relationboth sites and the main hydrological characteristics of both catchments (area,

permeability and slope) and stretches (latitude and altitude) .

1.3.2 REGIONALIZED STREAM FLOW.

If no data is available it is possible to use hydrological methods, called alsoregionalized methods, that are based on long-term rainfall and evaporation recordsand on discharge records for similar catchment areas.

Since the regionalization methods are aimed to represent long-termhydrologic behaviour on different time scale basis, through the analysis ofhomogeneous zones of climate, topography, soil, and vegetation, they are reliableonly if applied to given zones to predict flow at a given time scale. The use of thesemethods allows initial conclusions to be drawn on the overall hydraulic potential

without taking actual site observations, but require an accurate study of the methodand its applicability. In the case regionalization methods are used to estimate thestream flow, once the project looks likely to be feasible, it is recommended to followthis up with site measurements to asses at least the mean annual flow value.

1.3.3 THE FLOW DURATION CURVE (FDC)

Stream flow data given as an annual hydrograph simply shows the day-by-day variation in flow over a calendar year. From this hydrograph the Flow durationcurve (FDC) can be obtained by organising the daily data by magnitude instead ofchronologically.

FDCs of natural rivers are often very similar in a region, but can be affectedby soil conditions, vegetation cover, and to a lesser extent by catchment shape.They are also modified by man-made reservoirs, abstractions and discharges.Nevertheless, if the FDC for another stretch of the same river is known, it ispossible to get the FDC in the stretch of interest by extrapolation, using the ratio ofareas of the respective catchments, as long as due allowance is made on thespecific characteristics of soil, vegetation and man made devices.

Standardised FDCs, developed by statistical analysis of available recordsfrom neighbouring rivers of similar topographical character in a similar climate, arevery useful in evaluating stream flows at ungauged sites. These kind of methodscan be used only if developed by certified institutions.

If the mini-hydro development is planned to operate only during given

seasons of the year, FDCs should be produced for those periods of time, say forsix winter months or/and six summer months, by extracting the flow records for theparticular period from each year and treating these data as the whole population.


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The FDC should show how flow is distributed over a period (usually a year).The vertical axis giving the flow, while the horizontal axis gives the percentage ofthe year or period, or the number of days in a year or period that the flow exceedsthe value given on the y-axis.

EXAMPLE OF FLOW DURATION CURVE[FDC]

1.3.4 RESIDUAL OR COMPENSATION FLOW [DMV]

The residual flow is defined as the minimum flow that preserve aquatic life inthe stream. There is not a single criteria to define the residual flow. Severalmethods have been developed in different countries and some of these methodshave been introduced into the specific national or regional regulations on waterprotection. Therefore, the residual flow of each project should satisfy the currentwater law of the region where the mini-hydro development is proposed.

1.3.5 DESIGN FLOOD [QF]

Estimation of the design flood is necessary to obtain the required spillwaycapacity. The requirements regarding the design flood normally are specified innational legislation or regional guidelines, and distinguish between high, mediumand low hazard structures. In general mini-hydro plants can be considered asmedium low hazard structures in which it is recommended to discard the routingeffects of the reservoir. The spillway capacity then, shall exceed the peak flow of aflood with a specific return period, typically 100 - 500 years.

There are basically two ways to define a design flood: by statistical analysisof stream flow records, or by hydrological modelling of the catchment area. In mini-hydro developments, due to the less important structures that would not causedramatic consequences to life and people in case of failure, statistical analysis isnormally used.

Even though, if suffice data of the site is not available, it is possible to obtain

the design flood by one of the many hydrological watershed models that permitcalculation of the runoff for a certain catchment basin taking into account theaverage daily rainfall, the potential evapotranspiration, the soil composition, the

0

20

40

60

80

100

120

140

160

180

200

0 10 20 30 40 50 60 70 80 90 100

Percent time flow equalled or exeeded (%)

Flow(m3/s)

Total available water volume


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basin slope and area, the stream length, the snowmelt and its contribution to thedischarge and other parameters.

Whereas one or the other of the methods are used, the Hydrologic reportshould include a brief description of the method used, highlighting the basichypothesis and parameters assumed to calculate the design flood.

1.4 Plant capacity and energy output

The plant capacity and the average annual energy output of the proposedscheme should be obtained considering the net water volume passed through theturbine in a year. For this purpose is then necessary to take into account theresidual flow and the minimum technical turbine flow which depends upon theturbine type as shown hereafter:

Turbine type Qmin (% of Qdesign)

Francis 28 - 50

Semi Kaplan 20 - 30Kaplan 10 -15

The design flow [QD] has to be identified through an optimisation procedure inorder to achieve the best performance of the turbines along the year with the betteraverage annual energy production.

This feature can be done by analyzing the performance of two parameters:the capacity factor and the stream factor. The capacity factor [CF] is an index thatindicates how hard a turbine is working and can be obtained by means of thefollowing formulae:

annual energy output [kWh]

installed capacity [kW] 8760F T

E

C P= 4.

The stream factor [CS] measures the utilization of the water resource as:

useful water volume

Total water volumeSC = 5.

When the capacity factor approaches 1, normally the stream factor is small.This means that the turbines are working really hard but the water resource isbeing misused. On the contrary, when the stream factor approaches 1 the capacityfactor approaches zero indicating a misuse of the installed capacity. Optimizationusually leads to the best performance of both factors.

After setting the duration of the design discharge, the residual flow and theminimum technical flow, the useful water volume can be obtained by integration ofthe portion of the FDC bounded by the design discharge, the residual flow and theminimum technical flow.

Usually the flow value authorized in the water use permission named also,average annual discharge [QM], is the mean value of the useful water volume.

3ms

useful water volume [m ]

1 year [s]

3

MQ =

6.


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EXAMPLE OF CALCULATION OF USEFUL WATER VOLUME FROM THE [FDC]

The plant capacity [PC] to be declared in the application form should beobtained with the average discharge [QM] and net head [HN] neglecting theefficiency of the system.

kW M NCQ H

P1000

= 7.

with 9810 N/m3

specific weight of water.

As said before, if the scheme is a high head one, the gross head can beconsidered constant. In low head schemes the gross head normally is stronglydependent with the stream flow. Hence, in calculating the plant capacity andenergy production it is necessary to consider this dependence as shown in thegraph.

EXAMPLE OF GROSS HEAD VARIATION WITH STREAM FLOW

0

20

40

60

80

100

120

140

160

180

200

0 10 20 30 40 50 60 70 80 90 100

Percent time f low equalled or exeeded (%)

Flow(m3/s)

maximum flow

residual flow

minimum flowQD

useful water volume

0

500

1000

1500

2000

2500

0 10 20 30 40 50 60 70 80 90 100

Discharge (m3/s)

Power(kW)

0.0

1.0

2.0

3.0

4.0

5.0

GrossHead(m)

Power

Net head

QM

HG

PC


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The peak power PT which is actually the turbine or installed power of the

plant, should be estimated with the design flow QD and the net head HN as follows:

kW D NTQ H

P1000

= 8.

where represent the efficiency of the system

T G g t = 9.

T = turbine efficiency

G = generator efficiency

g = gearbox efficiency

t = transformer efficiency

The average annual energy output [E] is given as the actual developedpower along the year which can be obtained by the following expression:

useful water volume[kWh] N

g HE

3600

= 10.

where g is the gravity acceleration, HN is the net head.

In mini-hydro schemes it is useful to determine the Firm energy. The firmenergy is defined as the power that can be delivered by a specific plant during acertain period (usually a year) with at least 90 - 95% certainty. Normally, run-of-river schemes have a low firm energy capacity while hydropower plants withstorage reservoir have considerable capacity for firm energy. The firm energy is asignificant parameter in economic evaluation when the overall energy production issmall.

2. Technical description of the project

2.1 Diversion structure

2.1.1 WEIR

In mini-hydro schemes weirs are primarily intended to divert the river flow intothe water conveyance system leading to the powerhouse. The weir may produceadditional head and some storage capacity.

Weirs can be placed perpendicular, angular or lateral to the river axis.However, is a good practice to set the weir crest rectilinear and perpendicular to

the river axis. For low downstream water levels, the weir controls the flow anddefines the relationship between the upstream water level and the discharge asshown in the discharge rating curve of the figure.

At this level of the project it is not necessary to asses the structural stability ofthe weir or dam. Even though, some hydraulic features should be studied:

The discharge rating curve of the weir: On the discharge rating curve graph theresidual flow, the design discharge and the peak of the design flood with theirrespective water surface levels should be indicated precisely.


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EXAMPLE OF DISCHARGE RATING CURVE OVER A WEIR

The length and impact of the backwater effect for the design discharge and for thepeak of the design flood. In order to better estimate the upstream impact and theeventual damage due to the change of regime of the watercourse imposed by theweir, the water surface profile should be calculated for the whole length of thebackwater effect.

This calculations should be performed for at least for two flows: the designdischarge and the peak of the design flood. For this purpose, the shape of anumber of cross sections of the stream obtained by recent surveying topographicalwork are necessary. Special attention should be paid in modelling the crosssections interested by crossing structures such as bridges, culverts, etc.

EXAMPLE OF WATER SURFACE PROFILE

Hmin

H0

0

4

8

12

16

20

0 1 2 3 4

discharge Q

stage

h

QFQDDMV

Hmax

0 200 400 600 800 1000 1200 1400290

292

294

296

298

300

302

304

306

EXAMPLE Q = Design discharge

Distance (m)

Sta

ge(m)

Legend

Water surface

Ground

Left bank

Right bank

SEZ.16b...

SEZ.14bG.ST...

SEZ.13bG.STAMPA...

BRIDGE

SEZ.9bG.STAMPA

SEZ.10bG.STAMPA

SEZ.11bGEOMETRAS...

SEZ.20MAZZUCCHELLI

SEZ.19MAZZUCCHELLI

SEZ.18MAZZUCCHELLI

SEZ.16MAZZUCCHELLI

SEZ.15MAZZUCCHELLI

SEZ.13MAZZUCCHELLI

SEZ.12MAZZUCCHELLI

OLONA1

4

OLONA1

2

OLONA1

1

BRIDGE

OLONA0

8

OLONA0

7

OLONA0

6

OLONA0

5

OLONA0

4

OLONA0

3

OLONA0

2

OLONA0

1

Olona INTERMEZZO_2 Olona INTERMEZZO Olona MONTE

0 200 400 600 800 1000 1200 1400290

292

294

296

298

300

302

304

306

EXAMPLE Q = Design discharge

Distance (m)

Sta

ge(m)

Legend

Water surface

Ground

Left bank

Right bank

SEZ.16b...

SEZ.14bG.ST...

SEZ.13bG.STAMPA...

BRIDGE

SEZ.9bG.STAMPA

SEZ.10bG.STAMPA

SEZ.11bGEOMETRAS...

SEZ.20MAZZUCCHELLI

SEZ.19MAZZUCCHELLI

SEZ.18MAZZUCCHELLI

SEZ.16MAZZUCCHELLI

SEZ.15MAZZUCCHELLI

SEZ.13MAZZUCCHELLI

SEZ.12MAZZUCCHELLI

OLONA1

4

OLONA1

2

OLONA1

1

BRIDGE

OLONA0

8

OLONA0

7

OLONA0

6

OLONA0

5

OLONA0

4

OLONA0

3

OLONA0

2

OLONA0

1

Olona INTERMEZZO_2 Olona INTERMEZZO Olona MONTE


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The water surface profile can be calculated by means of any softwareavailable in the market as long as enough information about the assessment andreliability of the model used is presented.

Profile drawings should clearly indicate the level reached by the water, theright and left bank along the stream and the location and levels of the maincrossing structures. An example of a water surface profile is shown in the figure.

The water surface profile downstream for the peak of the design flood: If theproposed scheme does not include a spillway, a water surface profile downstreamthe weir is necessary to estimate eventual erosion phenomenon at the wire base orfurther downstream the river .

2.1.2 RESIDUAL FLOW DEVICE

The layout of the diversion works most assure the complete restitution of theflow to the river whenever the discharge is less or equal the residual flow. Thismeans that the project should contain a special device at the weir itself or at anyanother location, able to by-pass the diversion works and restore, immediately

downstream the weir, the flow to the river. Such device should operateautomatically without any man input. A good practice in this context is to place thelevel of the wire crest above the level required by the residual flow device toconvey the DMV.

2.1.3 FISH PASSAGEWAY

Mini-hydro-installations on rivers populated by fish migrating species or not,are subject to special requirements. In fact, fish population must not be swallowedinto the turbine and they should be free to transfer up or downstream at all times.Thus a water passage to by-pass the hydro-plant should be introduced.

A preliminary study about the biodynamic characteristics of each kind of fishpopulation of the interested river should be carried out.

To allow fish to pass upstream requires the construction of a special devicesuch as a 'fish ladder', which is usually a series of pools one above the other, with

water overflowing from the higher ones to the lower ones so that fish can jump upfrom one pool to the next. This structure should be adopted only if the fishpopulation is able to leap, if not, another type of fish passage device should be

RESIDUAL FLOW RATING CURVE DEVICE

300.00

300.50

301.00

301.50

302.00

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Stream Flow (m3/s)

Level(ms.l.m.)

Weir discharge rating curve

Residual flow device rating curve

DMV

Weir crest


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provided. Culverts, usually placed along one of the banks near the weir or lateralcanals are often also used as fish pass device in this case

Hydraulic design of these devices should fit the fish population characteristicsin particular the:

Fish length (fH) and body depth (fL) range,

Water temperature range suitable to fish life. Swim Speed Range and time to exhaustion (in sustained mode, prolongedmode, critical mode and burst mode)

Depth threshold for passage (verified for low flows)Velocity threshold for passage (verified for high flows) The maximum leaping velocity Vf (for species that are able to leap)

For example the plunging pools dimensions of a fish ladder must satisfy thefollowing expression:

2f

L

VH

2g= 11.

where Vf

is the maximum leaping velocity, g is the gravity acceleration and HL

isthe leap hight as shown in the figure.

DIMENSIONS OF A PLONGING POOL

Often the fish passage device is used also to convey the residual flow. Sincenot always the residual flow verifies the depth threshold for passage characteristicof the fish population, it becomes necessary to introduce a fish screen or any otheritem as a deterrent when flow is below the critical value.

2.1.4 SPILLWAY AND ENERGY DISSIPATION STRUCTURES

The spillway is the structure build to convey in a safety and efficient way thedesign flood. Mini-hydro schemes are normally of the run-off river type in which theweir itself controls the flow and defines the relationship between the upstream


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water level and the discharge. In fact the main function of the weir is to divert therequired flow whilst the rest of the water continues to flow over it. For this reason inthese kind of schemes the weir operates as a spillway when the design floodhappens.

The amount of water that can be spilled over a weir depends on the shape ofthe crest as shown in the figure. In order to avoid under-pressures that may lead tocavitation which will damage the downstream face of the weir and to asses thebehaviour of the weir as a spillway, it is necessary to design the geometry of thecrest for the peak flow of the design flood.

The ogee weir is hydraulically the better solution but it is very expensive. Insmall hydro plants it is seldom adopted.

For downstream water levels that are equal to or higher than the spillwaycrest level, the spillway becomes progressively submerged and its correspondingdischarge decreases. Furthermore, in presence of piles, the governing dischargewill depend on the shape and dimensions of the piles. All these aspects influencethe functioning of a spillway but are not mandatory at this level of the project.

CHARACTERISTICS OF DIFFERENT TYPES OF SPILLWAY

The flow spilled over the weir is usually supercritical with high flow velocitiesand turbulence that may produce severe erosion at the toe of the structure, mainlyif the riverbed is not erosion resistant. To avoid any damage downstream the weir,the hydraulic profile of the river should be verified and if necessary, a structuralsolution such as a stilling basin should be adopted.

2.2 Conveyance structure

2.2.1 INTAKE

A proper operation of a water intake should assure the diversion of water justup to the required design discharge into the power canal or into the penstock withthe minimum possible head losses. Besides, design of the intake should consider


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the possibility to handle debris and sediment transport and to avoid entering offishes.

To satisfy these conditions, the intake should be supplied with a trashrackwhose mesh must be fine enough to keep away from the turbine fishes and a goodpercentage of solid transport.

The cleaning of this mechanism should not be neglected at this level of theproject. Normally manual raking is only practicable for very small schemes or sites.Then, the introduction of an automatic raking device to clean the screen anddispose of the trapped debris should be foreseen.

2.2.2 CHANNELS, CANALS OR TUNNELS

In mini-hydro schemes the waterway is normally an artificial canal of regularcross-section and with a very mild slope, thus flow in it is subcritical with very lowfriction losses. The flow conveyed by a canal is a function of its cross-sectiongeometry profile, its slope, and its roughness. Conveyance of this kind of devicecan be obtained by the Manning equation:

23oQ AKR s = 12.

where Q[m3/s] is the conveyed flow, A [m2] wetted area, K[m1/3/s] is the Stricklerroughness coefficient which depends on the material of the channel walls, R[m] isthe hydraulic radius, given by the ratio A/Pwith and P[m] wetted perimeter and so[-] is the river bed slope. Special care should be paid to the choice of the Stricklercoefficient.

To avoid channel overtopping, a generous freeboard and a lateral spillway ina safety position should be provided.

2.2.3 PENSTOCK

Penstocks are normally used only to convey water into the power house. Inmini-hydro systems, penstocks can be plastic or metallic. The diameter is chosenas the result of a trade-off between penstock cost and power losses. As a goodpractice flow velocities in penstocks should not be larger than 5-7 m/s neither lowerthan 0.5 m/s.

In high head schemes the penstock wall thickness can be obtained with thefollowing expressions:

f

pDe

2

De

100

=

13.

where e [m] is the wall thickness of the pipe, p [Pa] is the maximum hydrostatic

pressure , D[m] the pipe diameter and f [Pa] the allowable tensile strength of thematerial

In low head schemes the penstock is subject to low pressures thus it is notnecessary to calculate the wall thickness since the second condition prevails.

2.2.4 TAILRACE

The tailrace is normally a short canal through which water returns to thestream after passing through the turbine. The tailrace most satisfy the sameconditions given above for the channel. The flow velocity in the tailrace should beverified (specially in schemes with impulse turbines such as Pelton) to avoid bed

erosion and to ensure that the powerhouse would not be undermined. If necessary,protection with concrete aprons should be provided between the powerhouse andthe stream.


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In low head systems the level at the tailrace determines the available nethead and influences the operation of the turbine when a reaction turbine isadopted. The available net head may have a decisive influence on the economicevaluation, thus, the tailrace design should ensure that during high flows in theriver the water in the tailrace does not rise so far that it interferes with the turbinerunner.

2.3 Power house

In small hydropower plants the power house is the building made to protectthe electromechanical equipment (turbo-generator) from the weather hardships.Dimensions of the power house are function of the number, type and power of theturbo-generators, of the specific geomorphology of the site and of the generallayout of the scheme.

2.3.1 INLET GATE OR VALVE

In mini-hydro schemes it is normal practice to introduce an automatic valve orgate between the turbine and the conveying system in order to allow the turbine to

disconnect from the hydraulic system in a short time. To reduce pressure surges inthe pipe due to this feature, a waterway to by-pass the turbine should be provided.

2.3.2 TURBINE AND CONTROL SYSTEM

The selection of the turbine depends upon the site characteristics, principallythe available head and design discharge, plus the desired running speed of thegenerator and whether the turbine will be expected to operate in reduced flowconditions. The approximate ranges of head, flow and power applicable to thedifferent turbine types are shown in the figure.

HEAD-FLOW RANGES OF SMALL HYDRO TURBINES

An important feature to be considered when choosing a turbine is itsefficiency performance for flows different from the design discharge. The

calculation of the average annual energy production should take into account thevariation of the turbine efficiency when operating at reduced flows. Typicalefficiency curves are shown in the following figure in which the turbine efficiency to


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the relative flow (Q/QD) is plotted for different turbines type. The efficiencyperformance of the different turbines show that in low head schemes, it could beworthy to adopt a more expensive Kaplan turbine which maintain high efficiencieswithin the whole range of flows with a better energy yield.

TURBINE EFFICIENCY FOR DIFFERENT RELATIVE FLOW

Turbine operation is normally triggered by control devices such as the wicket-gates, vanes, spear nozzles or valves. Actually, turbines are build for a given nethead and design discharge, any other value of these parameters will require anopening or closing of the control devices to keep either the outlet power, the levelof the water surface in the intake, or the turbine discharge constant.

In mini-hydro schemes connected to an isolated network, the parameter thatneeds to be controlled is the turbine speed, which controls the frequency of theproduced electricity.

2.3.3 GENERATOR AND SPEED INCREASER (IF NEEDED)

Generators are classified as Synchronous generators and Asynchronousgenerators as follows:

Synchronous generators: are self excited devices since they are suppliedwith a permanent magnet excitation system. Synchronous generators can runisolated from the grid and produce power since excitation is not grid-dependent

Asynchronous generators: They are simple induction motors with nopossibility of voltage regulation. This generators run at a speed directly related to

the system frequency. They are normally used in very small stand-aloneapplications as a cheap solution when the required quality of the electricity supplyis not very high.

In small hydro schemes as a rule standard generators should be installed soin turbine selection it must be considered that the generator, either coupled directlyor through a speed increaser to the turbine, should reach the synchronous speed.

2.3.4 PROTECTION SYSTEMS AND DC EMERGENCY SUPPLY

Power consumption of the power house in mini-hydro projects represent 1-3% of the plant installed capacity.

Small hydro schemes are normally unattended and operated through anautomatic control system. Alternative supplies, with automatic changeover, shouldbe used to ensure service in an unattended plant. It is generally recommended thatremotely controlled plants are equipped with an emergency 24 V DC back-up


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power supply from a battery in order to allow plant control for shutdown after a gridfailure and communication with the system at any time.

In mini-hydro plant developments, records of at least the headwater andtailrace should be made and the installation of the right equipment should beconsidered in the project

2.3.5 SUBSTATION

The so-called water-to-wire system usually includes the substation. A linebreaker must separate the plant from the grid in case of faults in the power plant.Power and current transformers metering should be considered at the connectinglink between the plant-out conductors and the take-off line to the grid. In highenvironmental sensitivity areas the substation should be enclosed in thepowerhouse.

The standard generation voltages of 400 V or 690 V allow for the use ofstandard distributor transformers as outlet transformers and the use of thegenerated current to feed into the plant power system. At this level of the projectnot other information is needed.

3. Economic and financial analysis.

The application file most contain an economic and financial analysis in which the wholeinvestment, the operation costs, rates, taxes, insurances and any other costs should be clearlyindicated together with the benefits and government grants. This study should demonstrate theeconomic feasibility of the project by means one of the known methods of economic evaluation. Acash-flow forecast for the whole lifetime of the project should be included.

3.1 Investment and costs for installed capacity

At this level of the project is worthless to produced a detailed constructioncost estimates, nevertheless, the cost of the most important items (weir, channel,penstock, powerhouse, turbo-generator) should be calculated with some accuracyin order to achieve a reliable total investment.

3.1.1 INITIAL INVESTMENT COST

Small hydro investment costs can be split into four segments:

Machinery. Should include the turbine, gearbox or drive belts, generatorand the water inlet control valve. For the same power, in general, high headmachines are smaller than low head machines and run faster, thus can beconnected directly to the generator without any speed increaser, therefore,machinery costs for high head schemes are lower than for low head schemes of

similar power. Civil Works: Should include all diversion works, the pipeline or channel to

carry the water to the turbine, the power house and machinery foundations, andthe tailrace channel to return the water to the river. The Civil Works are largely site-specific. On high head sites the major cost will be the pipeline; on low head sitesthe diversion works and the channel.

Electrical Works: The electrical system costs should take into account thecontrol system, the wiring within the turbine house, and a transformer if required,plus the cost of connection to the grid. These costs are largely dependent on themaximum power output. The connection cost is set by the local electricitydistribution company.

External Costs: This item should consider the whole engineering services ofa professional to design the plant and manage the installation plus the costs ofobtaining the licences, planning permission, etc.


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Average current costs are presented in the following table.

100KW-500 KW SMALL HYDRO INSTALLATION COSTS ( X 1000)

ITEM Lowhead Highhead

Electromechanical equipment 70 - 140 35 - 70

Civil works 35 - 115 35 - 95

Electrical works (no grid connection) 18 - 35 18 - 35

External costs 12 - 35 12 - 35

Total: 135 - 325 100 - 230

Generally, the cost per kilowatt of new schemes increases as size reduces,due to economy of scale and the fact that any scheme has a certain fixed costelement which does not greatly change with size

3.1.2 OPERATION AND MAINTENANCE COST

New mini-hydro projects usually foresee the introduction of modernautomated equipment which requires very little maintenance. Though, annualmaintenance costs should be no more than 1-1.5% of the total investment. Yet,within the maintenance costs one should include the replacement of the seals andbearings of the machine, or the replacement of the turbine itself and/or of thegenerator, valves, sluice gates, etc. which could be considered to happen once atleast each 10 years.

Operation annual costs should include as well all leasing payments,insurances, taxes, metering plus the licence annual cost.

To achieve an acceptable revenue the total annual running cost shouldmaintain under 5% of the total investment.

3.2 Benefits due to generation

The main income in running a mini-hydro plant regards the electricity sale. Incalculating the total income, it is necessary to consider other the electricity sale,the renewable obligation certificates (given to clean electricity producers in almostall countries of the European Community) and any other grants or incentives ifavailable.

3.2.1 TARIFFS

The tariff is the unitary electricity price [/MW] paid to the electricity producerby the supplier. Actually, electricity tariffs are not a stable entity since they varyconstantly influenced by the markets. Tariffs vary from one country to another andare strongly influenced also by national policy. It is therefore important to take intoaccount in the income calculation all these implications.

However, for the purpose of the economic analysis to be included in thewater use application, unless one has come to an agreement for a specificnegotiated tariff, it is advisable to compute the annual revenue with the averageannual price paid by the supplier the last year.

3.2.2 INCENTIVES

Electricity generated from renewable sources can be used to obtainRenewable Obligation Certificates which all the supply companies need in order to


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prove they are meeting the governments targets for renewable energy. Thesecertificates have a market value which vary over time, depending on how wellthese companies are doing in meeting their targets.

Besides the renewable obligation certificates, all along the EuropeanCommunity there are a number of supplementary incentives to promote renewableenergy developments, these are specific of each country. For example, in manycountries for domestic developers and other non-commercial owners, thegovernment has reduced the VAT payable on hydro-electric plant to 5% forsystems supplying buildings which are either residential or used for charitablepurposes.

Moreover, there are a wide range of regional funding mechanisms which canoffer grants towards small-scale developments of renewable energy projects.

3.3 Cash flow forecast analysis

Cash flow is essentially the movement of money into and out of a business.Cash Flow forecasts is the model of the way in which cash moves within the

project. Through Cash Flow forecasts it should be possible to demonstrate whetherthe predicted sales or income will cover the operation costs and whether a projectwill be sufficiently profitable to justify the effort put into it.

Cash Flow forecast should be carried out for the whole lifetime of the projecton a spreadsheet indicating clearly cash inflows and outflows.

EXAMPLE OFCASH FLOW FORECAST ANALYSIS


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3.4 Methods of economic evaluation

3.4.1 TIME VALUE OF MONEY

In any economic analysis involving economic value there are always twovariables, money and time. The time value of money principle is that an euro todayis worth more than an euro tomorrow, that means that money paid or received at agiven time has a different value if it is paid or received at another time. To comparepresent and future investments, it is then necessary to express cash flows incurrent value, that is to obtain the present value of each single future cash flow.

The term present value stands for the current value of a future amount ofmoney. To determine the present value the following formula is used:

( )o nn

1C C

1 r

= +

14.

Where Co is the present value of the future (nyears far) amount of money Cndiscounted at a given interest rate, also called discounted rate, r, for nnumber of

years.By means of the present value concept, investors can calculate the present

value of the future sales price of a mini-hydro plant. Thus if the investment is to beinteresting from an economic point of view, the today investment has to be sold ata much higher price in the future

3.4.2 PAYBACK METHOD

The payback method determines the number of years required for theinvested capital to be offset by resulting benefits. The required number of years istermed the payback recovery.

The payback method evaluates an investment project by the length of thepayback period. The payback period is the number of years that it takes for a

project to recover its initial investment. This period called also break-even periodindicates the time that it takes for an investment to pay for itself. The paybackperiod is expressed in years and should be obtained as:

Total investmentPayback period

Net cash inflow= 15.

By using the payback method the more quickly the cost of an investment canbe recovered, the more profitable is the project. This method is simple to use but itis attractive if liquidity is an issue, but does not explicitly allow for the time value ofmoney

3.4.3 RETURN ON INVESTMENT METHODThe return on investment (ROI) is an accounting valuation method that

compares the net benefits of a project, versus its total costs or book valueinvestment.

Net annual incomeROI

Book value of investment= 16.

Where the net annual income is obtained by subtracting the annual operationcosts to the revenue due to electricity plus certificates, etc.

ROI gives a quick estimate of the project's net profits, and can provide abasis for comparing several different projects. When using the ROI method toevaluate a project is better to consider cash flow rather than income data to take

into account the time value of money.


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3.4.4 NET PRESENT VALUE (NPV) METHOD

Is the most common method for evaluating an investment project. Under thenet present value method, the present value (PV) of all cash inflows from theproject is compared against the initial investment (I). The Net Present Value (NPV)determines whether the project is an acceptable investment. Under this method, a

project should only be considered if the NPV value is positive (NPV > 0).

The formula for calculating NPV, assuming that the cash flows occur at equaltime intervals and that the first cash flow (negative and represented by the initialinvestment I) occurs at the end of the construction period (j=0) is:

( )

( )n j jj

j 0

B CNPV

1 r=

=

+ 17.

Where:(Bj- Cj) represent the net cash inflow at the end of each periodj.

r= the periodic discount rate. If j= 3 months, r= of the annual discountrate.n= total number of periodsjin the project lifetime.The difference between revenues and expenses, both discounted at a fixed,

periodic interest rate, is the net present value (NPV) of the investment. Therefore,net present value is an amount that expresses how much value an investment willresult in todays monetary terms.

3.4.5 BENEFIT-COST RATIO[BCR].

The cost-benefit ratio is a simple calculation that depicts the total financialreturn for each euro invested in the project. The method compares the presentvalue of the overall benefits and the overall investment along the lifetime of the

project, on a ratio basis. as follows:

( )

( )

n j

jj 0

n j

jj 0

B

1 iBCR

C

1 i

=

=

+=

+

18.

Where the numerator represent the present value of the total revenue andthe denominator the present value of the investment. Projects with a ratio of lessthan 1 should be discarded.

3.4.6 INTERNAL RATE OF RETURN METHOD [IRR]

The Internal Rate of Return is the discount rate that makes the present valueof all net cash flows of the project equal to zero. The higher a project's internal rateof return, the more advantageous it is. As such, IRR can be used to rank differentapplications for the same site. Assuming all other factors are equal among thevarious projects, the project with the highest IRR would be considered the best.

Once the rate is known, it can be also compared to the cost of borrowingmoney. If the IRR is less than the cost of borrowing used to fund the project, theproject will clearly be a money-loser.

To find the IRR a process of trial and error is used, whereby the net cash flowis computed for various discount rates until its value is reduced to zero.


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4. Environmental impact study.

Even if hydropower is considered clean energy because does not produce carbondioxide or liquid pollutants, their location in sensitive areas could produce local impacts that arenot always negligible. These impacts normally are proportional to the installed capacity, therefore

in mini-hydro developments should be quite small. Nevertheless in most of the countries of theEuropean Community, an environmental impact assessment (EIA) must be carried out in order toget the licence for water (Directive 2000/60/CE Water Framework Directive).

This study is a scientific and technical analysis, which makes an inventory of the presentsituation and foresees the consequences on the environment to be expected from theimplementation of the project. It concerns the fauna and the flora, the landscapes, the ground, thewater, the air, the climate, the natural surroundings and the biological equilibriums, the protectionof goods and of the cultural patrimony, the comfort of the neighbourhood (noise, vibrations,smells, lightning), hygiene, security, public salubriousness and health.

Recently, in order to encourage investors towards mini-hydro developments, authorities ofmany European countries do not require a complete EIA for plants with installed capacity less

than 3MW. Nevertheless any application for water use should include an environmental studywith an accurate description from the environmental point of view of the site and with indicationsabout all burdens and impacts at local level that the project could produce. The foreseenmitigation strategies and measures should also be included. The following discussion concernsonly these kind of projects.

4.1 Environmental general description of the site

In order to be able to identify the overall environmental impact of theproposed scheme it is necessary that developers perform an accurate survey ofthe site to collect all the information. Applicants should then describe the wild life

specifying the kind and state of the vegetation and the different species of birds,mammals and of course the aquatic population. They should also indicate the airand water quality and describe the level of human presence and any humanactivity that could be disturbed by the mini-hydro development. Photographsshould be included.

4.2 Impacts identification

Environmental Impacts of mini-hydropower schemes are highly location andtechnology specific. A high mountain diversion scheme situated in a highlysensitive area is more likely to generate an impact than an integral low-headscheme in a valley.

Within the European community an exhaustive description of possibleenvironmental impacts consequent to hydropower plants, made by groups ofexperts that perform Environmental Impact Assessments, are available in literature(see the tables here after). These studies suggest to distinguish temporary impacts(likely does present only during the construction period) from permanent (due tooperation of the plant along its lifetime).


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4.2.1 IMPACTS DURING CONSTRUCTION

The environmental study should analyze only the items of the following tablesconcerning the specific project.

EVENTS DURING CONSTRUCTIONPERSONS OR

THINGS AFFECTEDIMPACT PRIORITY

Geological Surveys Wildlife Noise Low

Existing Vegetation Cutting Forestry Alteration of habitat Medium

Enlargement of Existing Roads General publicNew opportunities,alteration of habitat

Medium

Earth Moving Site geology Slope stability Low

Tunnels Excavation Site hydro-geologyAlteration ofgroundwater

circulation

Low

Permanent Filling Material onSlopes

Site geology Slope stability Low

Embankment RealisationAquatic life, sitehydro-morphology

Alteration of riverhydraulic

Medium

Creation of Temporary EarthAccumulations

Site geology Slope stability Low

Temporary Displacement ofPersons, Roads, Electric Lines

General public Negligible

Realisation of Roads and Shedsfor the Yard

Wildlife, generalpublic

Visual intrusion,wildlife disturbance

Low

Water Courses Dredging Aquatic ecosystem Alteration of habitat Medium

Temporary Diversion of Rivers Aquatic ecosystem Alteration of habitat High

Use of Excavators, Trucks,Helicopters, Cars for thePersonnel, Blondins


Noise High

Human Presence During theWorks on Site


Noise Low


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4.2.2 MPACTS DURING OPERATION

EVENTS DURING OPERATIONPERSONS OR

THINGS AFFECTEDIMPACT PRIORITY

Renewable Energy Production General public Reduction of Pollutants High

Watercourses Damming Aquatic ecosystem Modification of habitat High

Permanent Works in the Riverbed Aquatic ecosystem Modification of habitat High

Diversion of Watercourses Aquatic ecosystem Modification of habitat High

Penstocks Wildlife Visual intrusion Medium

New Electric LinesGeneral public,wildlife

Visual intrusion Low

RiprapsAquatic ecosystem,general public

Modification of habitat,visual intrusion

Low

LeveesAquatic ecosystem,general public

Modification of habitat,visual intrusion

Low

Flow Rate modification Fish Modification of habitat High

idem Plants Modification of habitat Medium

idem General publicModification ofrecreational activities

Noise from electromechanicalequipment

General public Alteration of life quality Low

Removal of material fromstreambed

Aquatic life,General public

Improvement of waterquality

high

4.2.3 IMPACTS FROM THE ELECTRIC LINE

Above ground transmission lines and transmission line corridors can have anegative impact on the landscape. These impacts can be mitigated by adapting theline to the landscape, or in extreme cases by burying it.

4.3 Environmental impacts mitigation

When possible, the magnitude of the identified environmental impacts shouldbe established by comparing them with the current regulation. For this purpose, theEuropeans Community in the last years has issued several regulations indicatingthe tolerable range concerning different environmental items such as air and waterpollution, noise level, etc.

Different mitigation measures can be adopted to reduce the sameenvironmental impact. The choice of one measure from another normally is followssubjective arguments or economic reasons. Therefore, one could accept anymitigation measure or strategy as far as it meets the target.

Mitigating measures can be directly negotiated and agreed with the licensingauthorities.

Any mitigation strategies incorporated in the project will represent a costwhich should represent a small percent of the total investment.

5. Grid connection characteristics.

Excluding isolated schemes, any other plant cannot be operated without a connection tothe grid.

Normally the connection to the grid has to be negotiated directly with the local electricitysupplier and does not concern water rights. However, it is worthwhile to consider this item at this


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level of the project. In fact the specifications or conditions for connecting to the grid can changethe feasibility of a scheme.

Particular care should be paid to the connection capacity of the grid. A connection to asaturated grid is more expensive than a simple one, due to the fact that in the first case the gridshould be reinforced to accept further connections. Moreover, to give a right estimate of the

connection cost, it is necessary to know which connection have to be planned (high or lowvoltage) and the distance to the connection.

6. Land properties information.

Water use applications for a hydropower purposes should also include enough informationabout the land ownership interested by the whole scheme.

In general the mini-hydro developer is not the owner of all or part of the land necessary forthe project. Therefore, leasing agreements between the landlord and the developer should bedrawn up to establish the right to use the necessary land areas and also to define theresponsibilities of the leaseholder.

If no agreement is reached, authorities can insist that the landlord agrees in the publicinterest. No project can proceed unless the right to use all the land is achieved and certainpermission is granted to use all of the land required both to develop completely the scheme andto have the necessary access to it.

Depending on the juridical status of the land, an authorisation to reclaim the land shouldbe requested whenever a natural environment or sensitive zone will be spoiled as a consequenceof the project construction and/or operation.

If all the land or part of it is leased, then there will be an annual rent to pay to beconsidered in the economic evaluation.

7. Supporting documents.

7.1 Construction schedule

In order to support authorities to better national or regional plan hydropowerdevelopment, a construction schedule indicating the succession and duration ofeach stage of the construction should be included.

EXAMPLE OFACONSTRUCTION SHCHEDULE

FASE DI LAVORO

Installazione cantiere

Scavi e riempimenti

Opere civili canali di

carico e di restituzione,vasca di calma,

traversa, soglia

sfiorante, fabbricarocentrale e misuratore di

portata

Paratoie, panconaturee automazioni

Installazione macchine

allacciamento rete

elettrica

Impianti ed automatismi

Prove e regolazioni

Finiture, ripristini e

opere di mitigazioneambientale

MESI

1 2 3 4 125 6 7 8 9 10 11


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7.2 Developer information

Information about the legal and financial position of applicants is desirable,among these:

Legal name and names of directors of board, (if the applicant is acorporation)AddressNationalityOrganisation chart,Recent financial statements, including the balance sheets and the income

statements of recent years.Business plan, covering at least a long period.

8. Maps Drawings and Reports.

Applications with technical reports including graphs, shop drawings, and photographs selfexplanatory are preferable. All Applications most include the following and drawings maps andreports:

8.1 MAPS AND DRAWINGS:

8.1.1 SITE PLAN

Project location shown on regional and vicinity maps.(scale 1:10000 1:50000)

8.1.2 TOPOGRAPHIC MAP OF THE EXISTING SITE CONDITIONS

To include terrain contours, buildings or structures, utilities, drainage, andother physical features on or near the project site. For small projects, this

information can be shown in the site.(scale 1:2000 1:10000)

8.1.3 PROPOSED SITE PLAN.

Showing property boundaries, construction limits, and exactly definedlocations and elevations of finished new structures.

(scale 1:2000 1:10000)

8.1.4 ENGINEERING AND DETAILED DRAWINGS.

Showing detailed layout and dimensions of the main structures: weir and/orspillway, powerhouse, channel, tailrace, intake, etc.

(scale < 1:5000)

8.2 REPORTS:

8.2.1 GENERAL REPORT.

8.2.2 HYDROLOGICAL AND HYDRAULIC STUDY.

8.2.3 GEOTECHNICAL REPORT

8.2.4 ENVIRONMENTAL STYDY

8.2.5 ECONOMIC AND FINANCIAL ANALYSIS


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9. REFERENCES:

1. European Small Hydropower Association - ESHA Guide on How to Develop a SmallHydropower Plant 2004

2. The British Hydropower Association - BHA A Guide to UK Mini-Hydro Developments.2006

3. Centre for Rural Technology, Nepal (CRT/N) - Sustainable Energy Solutions in South AsiaINFORSE Manual on Micro Hydro Development Tripureshower, Kathmandu, 2005

4. Altener Community Programme - Integrated Plan for Renewable Energies IPRE. Studiodi fattibilit per la Riabilitazione delle Centrali Minihydro. 2001.

5. Ing. Marco Pigni Working paper of the TIS Innovation Park. Gli incentivi alle fontirinnovabili: i certificati verdi e le novit introdotte dalla Finanziaria 2008 Bolzano, 13giugno 2008

6. ENEA Libro Bianco per la valorizzazione energetica delle Fonti Rinnovabili. Roma, 19997. Gestore Mercato Elettrico GME Testo Integrato della Disciplina del Mercato Elettrico.Roma, 2008

8. F.H. White, "Fluid Mechanics", MacGraw-Hill Inc. USA9. H. Chaudry. Applied Hydraulic Transients, Van Nostrand Reinhold Co. 197910. , V.T. Chow, Open Channel Hydraulics, McGraw-Hill Book Co., New York 195911. S. Khennas A. Barnett. Department for International Development. Best Practices for

Sustainable Development of Micro Hydro Power in Developing Countries. U.K., 200012. U.S. Department of Energy. Water Energy Resources of the United States with Emphasis

on Low Head/Low Power Resources Energy Efficiency and Renewable Energy Wind andHydropower Technologies. Idaho National Engineering and Environmental Laboratory,2004

13. Regione Lombardia. Disponibilit ed Ottimizzazione nelluso della Risorsa Idrica-Parametri per lo sfruttamento Idroelettrico Quaderni Regionali di Ricerca, 33, 1999

14. H.C. Huang and C.E. Hita, Hydraulic Engineering Systems, Prentice Hall Inc.,Englewood Cliffs, New Jersey 1987.

15. T. Jacob, "Machines hydrauliques et quipements lectro-mcaniques", EPFL 200216. J. Fonkenell, How to select your low head turbine, Hidroenergia 1991.17. European Commission - "Externalities of Energy - Volume 6 Wind and Hydro" EUR 16525

EN18. U.S Department of Agriculture. National Inventory and Assessment Procedure for

Identifying Barriers to Acquatic Passage at Road-Stream Crossings. FishXing Version 3.0Beta, 2006.

19. : Renewable Energy and Liberalisation in Electricity Markets REALISE-Forum Final

conference Proceedings Berlin, November 2-3, 2006


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20. Final conference Renewable Energy and Liberalisation in Electricity Markets:

Lessons and Recommendations for Policy Berlin, November 2-3, 2006

21. Working paper of the European Commission Electricity from renewable sources and theinternal electricity market.

minihydro water use application doc

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