HomeMy WebLinkAboutIsolated Systems with Windpower An Implementation Guideline Riso 06-2001 Risø-R-1257(EN)
Isolated Systems with Wind Power
An Implementation Guideline
Niels-Erik Clausen, Henrik Bindner, Sten Frandsen,
Jens Carsten Hansen, Lars Henrik Hansen, Per Lundsager
Risø National Laboratory, Roskilde, Denmark
June 2001
Abstract The overall objective of this research project is to study the devel-
opment of methods and guidelines rather than "universal solutions" for the use
of wind energy in isolated communities. So far most studies of isolated systems
with wind power have been case-oriented and it has proven difficult to extend
results from one project to another, not least due to the strong individuality that
has characterised such systems in design and implementation.
In the present report a unified and generally applicable approach is attempted in
order to support a fair assessment of the technical and economical feasibility of
isolated power supply systems with wind energy.
General guidelines and checklists on which facts and data are needed to carry
out a project feasibility analysis are presented as well as guidelines how to carry
out the project feasibility study and the environmental analysis.
The report outlines the results of the project as a set of proposed guidelines to
be applied when developing a project containing an application of wind in an
isolated power system. It is the author’s hope that this will facilitate the devel-
opment of projects and enhance electrification of small rural communities in
developing countries.
ISBN 87-550-2860-8; ISBN 87-550-2861-6 (internet)
ISSN 0106-2840
Print: Danka Services International, 2001
Risø-R-1257(EN) 3
Contents
Preface 5
Glossary 6
1 Introduction 7
1.1 Background 7
1.2 Objectives 7
2 State of the Art - Technology 8
2.1 State of the Art 8
2.2 Categorised Power Systems 13
3 State of the Art – Economics 15
4 Fact Finding 15
4.1 Wind Resources & Climate 15
4.2 End User Needs and Load Demand 16
4.3 Existing Power Supply 17
4.4 Physical Planning & Infrastructure 18
4.5 Development Trends 18
5 Project Feasibility Analysis 19
5.1 Wind Resource 19
5.2 Site Selection 19
5.3 Electrical Design 20
5.4 Technical Performance 21
5.4.1 Performance Characteristics 21
5.4.2 System Configuration and Operating Strategy 22
5.4.3 Technical Performance Verification 22
5.5 Economic Performance 22
5.5.1 Project costs 23
Investment costs 23
Running costs 24
O&M costs 24
Retrofit & salvage costs 24
Extraordinary project costs 24
5.5.2 Cost of Energy, COE 25
5.5.3 Value of Energy, VOE 25
Primary power supply 25
Optional loads 25
Deferrable loads 25
Externalities 26
5.5.4 Development Scenarios 26
5.5.5 Assessment of Results 27
5.6 Modelling & Simulation 27
5.7 Uncertainties and Sensitivity Analysis 28
5.8 Environmental Scoping 29
Scoping document 29
6 Environmental Impact Analysis 30
4 Risø-R-1257(EN)
6.1 Diesel Generating Set 31
6.2 Wind Turbines 31
6.3 Desalination 31
6.4 Battery Storage 31
6.5 Socio-economic and Sociological Issues 31
7 Institutional and Legal Framework 32
7.1 Legal Issues 32
7.2 Ownership and Responsibilities 32
7.3 Stakeholders 33
7.4 Technology Carriers 33
7.5 Sustainability / replication 33
8 Financing 33
9Implementation 34
10 Conclusion and Recommendations 34
References 36
Appendix A Tables and Forms for Fact Finding 38
Appendix B WAsP 43
Appendix C Environmental Assessment 45
Appendix D Proposed Questionnaire on Existing Power System 58
Risø-R-1257(EN) 5
Preface
The present project has been financed by the Danish Ministry of Energy under
the energy research programme (EFP97), jour. no. 1363/0022.
Until now studies of isolated systems with wind power have mostly been case-
oriented. Thus it has been difficult to extend results from one project to another,
not least due to the strong individuality that has so far characterised such sys-
tems and their implementation. Therefore, a main objective of the present proj-
ect is to develop and present a more unified and generally applicable approach
for assessing the technical and economical feasibility of isolated power supply
systems with wind energy. As a part of the project the following tasks were car-
ried out: Review of literature, field measurements in Egypt, development of an
inventory of small isolated systems, overview of end-user demands, analysis of
findings and development of proposed guidelines.
The project is reported in one main report and four topical reports, all of them
issued as Risø reports:
Isolated Systems with Wind Power
• Main Project Report (Risø R-1256)
• Implementation Guideline Report (Risø R-1257)
• Review of Relevant Studies of Isolated Systems (Risø R-1109)
• Results of Measurements from Egypt (Risø R-1240)
• Inventory of Isolated Systems in Egypt (Risø, I-1703)
The present report is the Implementation Guideline Report Risø R-1257, pre-
senting a unified and generally applicable approach for assessing the technical
and economical feasibility of isolated power supply systems with wind energy.
The guideline is a living document that should be updated when significant de-
velopments in the technology or the market conditions and commercial activi-
ties occur. The present report is the first version. Please send your comments
and contributions by email to windconsult@risoe.dk or fax +4546775083 att:
Niels-Erik Clausen. Thank you.
6 Risø-R-1257(EN)
Glossary
BOO Build - Own - Operate
BOOT Build - Own – Operate - Transfer
COE Cost of energy
DGS Diesel Generator Set
DRE Decentralised Renewable Electrification
EDF Electricité de France
EMS Energy Management System
ESMAP WB Energy Sector Management Assistance Programme
ETDE Energy Technology Data Exchange
EWDS European Wind Diesel Software Package
GEF Global Environmental Facility
GUI Graphical User Interface
IGBT Isolated Gate Bi-polar Transistor
IEA International Energy Agency
IEC International Electro-technical Commission
IHRE Integrated Hybrid Renewable Energy
IRES Integrated Renewable Energy System
IRR Internal Rate of Return
LAC Levelized annual costs
LHV Lower Heating Value
LPC Levelized production cost
LOLE Loss of load expectancy
LOLF Loss of load fraction
LOLP Loss of load probability
LTMC Long term marginal cost
NPV Net present value
PAS Publicly Available Specification
PCF Prototype Carbon Fund
PV Photovoltaic
O&M Operation and Maintenance
QPW Quattro Pro for Windows
PPA Power Purchase Agreement
RAPS Remote Area Power–supply System
RE Renewable Energy
ROE Return on Equity
SHS Solar home system(s)
SQI Service Quality Index
STMC Short term marginal cost
UNDP United Nations Development Programme
VOE Value of Energy
WB World Bank
WD Wind-diesel
WECS Wind Energy Conversion System
WMO World Meteorological Organisation
WTG Wind Turbine Generator
Risø-R-1257(EN) 7
1 Introduction
The project is based on the assumptions that isolated systems with a high degree
of wind energy penetration constitute technically reliable options and that they
can be made cost-competitive in the near future. In addition, it is assumed that
such systems have their major market potential both as distributed generation in
large utility grids in the developed world and as local power supply in 1st, 2nd
and 3rd world countries.
In both applications such systems are subgroups of systems that are often re-
ferred to as Decentralised Renewable Electrification (DRE) systems. In the ba-
sic form, where wind turbines are connected to local diesel power stations, the
systems are referred to as Wind Diesel (WD) systems. In the more general form,
where several renewable energy sources and support technologies may be in-
cluded, the systems are frequently referred to as Integrated Hybrid Renewable
Energy (IHRE) Systems.
1.1 Background
The background for the project is the perception that there is a large potential
world wide for energy supply to remote and isolated villages with local power
supply systems characterized by large wind resources and high energy produc-
tion costs.
In such places the inclusion of wind energy in the energy production can be
very attractive and beneficial, but best practices for project implementation are
missing in terms of
• Overview of methodologies and tools
• Documented examples of cases and potential locations
• Functional outlines of guidelines based on practical experience
• Realistic implementation strategies aimed at market formation
The project aims at addressing all these issues in an attempt to present a unified
and generally applicable approach for assessing the technical and economical
feasibility of isolated power supply systems with wind energy. Each issue is
addressed in a separate project report, and this report is the report on functional
guidelines for isolated systems with a high proportion of wind energy.
1.2 Objectives
The overall objective of the present report is to assist the dissemination of the
use of wind energy in isolated communities by contributing to the development
of operational engineering design- and assessment methods for isolated elec-
tricity supply systems with a large contribution of wind energy by presenting an
outline of a functional set of guidelines and recommendations based on practical
experience.
8 Risø-R-1257(EN)
The difference between guidelines and standards is illustrated by the two types
of documents, that are now being developed in the framework of the IEC:
Guidelines deal with project implementation related elements of DRE systems
and may include guidelines for system selection, bid and contract, quality assur-
ance, operation, maintenance and overall system classification. Several versions
of project implementation guidelines may be envisaged for various types and
classes of systems
Standards deal with the specific technical elements of DRE systems and is the
responsibility of individual technical committees in the national and interna-
tional standardisation framework, that include IEC, CENELEC and other bod-
ies. The standards are unique, and all project implementation guidelines should
refer to one and the same set of RE systems standards
These definitions are adopted in the development of IEC/PAS 62111 document
(EDF, 1997) for small DRE systems for rural electrification in 3rd world coun-
tries.
A basic philosophy of the presented work is that wind energy should only be
introduced in power systems when it is applicable and beneficial, rather than
introducing wind power for demonstration purposes in projects not well suited
for wind energy.
2 State of the Art - Technology
The main purpose of the first part of this section is to uncover “state of the art”
from a technical point of view. The second part sets up a framework on how to
characterise power systems with wind energy.
2.1 State of the Art
The main focus of this paragraph is on state-of-the-art of wind turbines and
power systems with wind power. Since the technical know-how and perform-
ance of wind turbines are non-uniform a definition for categorisation of wind
turbines will be introduced. Power systems with wind power are assessed by
literature.
First of all, wind turbines can be divided into five groups with respect to the
range of the nominal power as listed in Table 1. The power limits presented
below are approximate and should be seen as a guideline only.
Table 1. Categorisation of wind turbines.
Nominal power Typical application
< 1kW Micro’s
1-10kW Wind home
10-200kW Hybrid/Isolated systems
200-1MW Grid connected – single or in cluster
> 1MW Offshore (or onshore) wind farms
Risø-R-1257(EN) 9
The present state of the art on wind turbines has been analysed in (L.H.Hansen
et al., 2001). The main results are listed in Table 2, outlining the applied con-
cept of the two largest turbines from each manufacturer of the top-8 suppliers
world wide.
Table 2. Applied concept of the two largest (i.e. newest) wind turbines from
each manufacture of the top 8 suppliers world wide. Source [Hansen et al.,
2001].
Manufacturer
(top 8 supp.)
Wind
turbine
Cofigu-
ration
Power control
features
Comments
NM 2000/72 a Active stall Two speedNEG Micon
(Denmark)NM 1500C/64 a Stall Two speed
V80 – 2 MW c Pitch and
variable speed
Range: 905 rpm.
to 1915 rpm.Vestas
(Denmark)V66 – 1.65 MW b Pitch and
OptiSlip
Range: 1500 rpm.
to 1650 rpm.
G52 – 850 kW c Pitch and
variable speed
Range: 900 rpm.
to 1650 rpm.Gamesa
(Spain)G47 – 660 kW c Pitch and
variable speed
Range: 1200 rpm.
to 1626 rpm.
E-66 – 1.8 MW d Pitch and
variable speed
Gearless. Range:
10 rpm. to 22 rpm.Enercon
(Germany)E-58 – 1 MW d Pitch and
variable speed
Gearless. Range:
10 rpm. to 24 rpm.
1.5s – 1.5 MW c Pitch and
variable speed
Range: 989 rpm.
to 1798 rpm.Enron Wind
(USA)900s – 900 kW c Pitch and
variable speed
Range: 1000 rpm.
to 2000 rpm.
2 MW a Active stall Two speedBonus
(Denmark)1.3 MW a Active stall Two speed
N80/2500 kW c Pitch and
variable speed
Range: 700 rpm.
to 1303 rpm.Nordex
(Germany)N60/1300 kW a Stall Two speed
D4 – 600 kW c Pitch and
variable speed
Range: 680 rpm.
to 1327 rpm.Dewind
(Germany)D6 – 1.25 MW c Pitch and
variable speed
Range: 700 rpm.
to 1350 rpm.
The letter concerning the configuration in Table 2 denotes:
a) a fixed speed wind turbine using an asynchronous generator with cage
rotor, a soft starter and a battery bank for reactive power compensation.
b) a variable speed wind turbine using a doubly fed asynchronous genera-
tor implemented in a setup known as OptiSlip (used by Vestas since the
mid 1990’s).
c) a variable speed wind turbine using a doubly fed asynchronous genera-
tor where the rotor is connected to the grid through a frequency con-
verter.
10 Risø-R-1257(EN)
d) a gearless variable speed wind turbine using a multipole wound syn-
chronous generator, where the stator is connected to the grid through a
frequency converter and the rotor through a rectifier.
Based on the findings in [Hansen et al., 2001], the present “state-of-the-art”
large wind turbine is a 3 bladed upstream machine with tubular tower using:
• active stall with a two speed asynchronous generator, or
• pitch control combined with variable speed. Moreover, the variable speed
concept is mainly realised using configuration “c”, i.e. a doubly fed induc-
tion generator with a rotor connected IGBT based frequency converter.
• only one of the top-10 manufactures is building a gearless (variable speed)
wind turbine.
The above characteristics are for a typical main-stream wind turbine. Besides
that a number of alternative wind turbine designs exist. As described in
(L.H.Hansen et al., 2001) Lagerwey is using configuration “d”, but with a 6
phased wound synchronous generator. Nordic Windpower promotes configura-
tion “a” in a two bladed upwind version. And Gaia is using configuration “a” in
a two bladed downwind version. Vergnet is also using configuration “a”, in a
two bladed as both upwind or downwind versions. Scanwind has started the
construction of a wind turbine using a configuration with a permanent magnet
synchronous generator based on the Windformer and a DC grid.
The present state of the art of power systems with wind energy is more difficult
to assess. Findings in (A.L.Pereira, 2000) will be quoted to give an impression.
In Table 3 an overview of hybrid power systems at research facilities through-
out the world are listed, while Table 4 presents hybrid power systems installed
throughout the world during the last decade.
Table 3. Selected list of hybrid power systems at research facilities. Source
[Pereira, 2000].
Lab. / Country
Installation
year
Die-
sel
(kW)
WTG
(kW)
Dump
load
Con-
sumer
load
Storage
(kWh)
Features
NREL / USA
1996
2 x 60 1 x 20a
1 x 75a
1 x 20c
1 x 10e
1 x 50f
– 100kW 16 (24V)
180
(120V)
3 AC buses
3 DC buses
PC based control system
Advanced data acquisition
system
CRES /Greece
1995
1 x 45 1 x 30
a 45 20kVA – PC based control system
DEWI /Germany
1992
1 x 30 1 x 50
a
1 x 30b
? 75kVA
127 x 1kW
??
RAL /England
1991
1 x 85 1 x 45
b 72kW 48kW 45 (fly-
wheel)
Dedicated microcomputer
controller
PC data-logging system
EFI /Norway
1989
1 x 50 1 x 55a
1 x 55b
55kW 40kW
20kVAr 27 Dedicated microcomputer
controller
Data acquisition w/ transient
recorder
RERL–UMass /
USA
1989
1 x 15 1 x 15
a 16kW
(1994)
16kW
(1994)
–PC based control system
4 operating strategies
Advanced data acquisition
Risø-R-1257(EN) 11
system (1994)
Rotary converter AC-DC-AC
IREQ /Canada
1986
1 x 35 1 x 50
c 17kW 50kW ––
AWTS /Canada
1985
2 x 50 1 x 40b
1 x 35c
1 x 65d
1 x 80e
1 x 50f
190kW 115 ––
RISØ /Denmark
1984
1 x 30 1 x 55
b 75kW – 30 (400V)
(1997)
PC based control system
Sophisticated data acquisition
system
Notes: (a) wind turbine simulator; (b) fixed speed induction generator; (c) VAWT, fixed speed induction gen-
erator; (d) two speed induction generator; (e) variable speed synchronous generator; (f) downwind fixed speed
induction generator.
12 Risø-R-1257(EN)
Table 4. Selected list of relevant hybrid power systems installed throughout the
world in the last decade. Source [Pereira, 2000].
Site / Country
Operation period
Diesel
(kW)
WTG
(kW)
Dump
load
Other loads
(kW)
PV
(kW)
Storage
(kWh)
Wind penetra-
tion
Sal / Cape Verde
1994–2001
2 x 500
1 x 800
1 x 620
1 x 400
2 x 300 – 2 x 250 (RO
desalination)
1 x 60
– – 22% (month)
14% (3years)
Mindelo / Cape
Verde
1994–2001
2 x 2300
2 x 3300 3 x 300 –
1 x 250
(RO)
1 x 500
(RO)
2 x 400-750
– – 17% (month)
14% (3years)
Dachen Island /
China
1989–2001
1 x 280
1 x 256
2 x 100
1 x 560
3 x 55
2 x 20
127 – – –26% (month)
15% (years)
Fuerteventura /
Canary Island
1992–2001
2 x 75 225 100
16.5 (RO)
8 (Ice)
70 (Lights)
–– ?
Foula Island /
Shetland Islands
1990–2001
1 x 28
1 x 18
(hydro)
1 x 60 90
25
96 (heating) – 1400
(hydro)
70%
(3months)
La Desirade /
Guadeloupe
1993–2001
1 x 160
3 x 240
12 x 12 – – – – 40% (instan-
taneous)
Marsabit / Kenya
1988–2001
1 x 100
1 x 200
150 – – – – 46% (3years)
Cape Clear /
1987–1990
1 x 72 2 x 30 – – – 100 70% (instan-
taneous)
Rathlin Island /
Northern Ireland
1992–2001
1 x 48
1 x 80
1 x 132
3 x 33 – – – 73 100% (in-
stantaneous)
70% (year)
Kythnos Island /
Greece
1995–2001
3 x 125
2 x 250
3 x 633
5 x 33
1 x 150
– – 100 330 ?
Frøya Island /
Norway
1992–1996
1 x 50 1 x 55 72 – – 27 100% (in-
stantaneous)
94%
(8months)
Denham / Austra-
lia
1998–
2 x 288
2 x 580
1 x 230 – – – – 70% (instan-
taneous)
23%
(6months)
Lemnos Island /
Greece
1995–
2 x 1200
2 x 2700
1 x 2600
8 x 55
7 x 100
–––– ?
Risø-R-1257(EN) 13
2.2 Categorised Power Systems
In the following a categorisation of power systems is suggested. This is useful
as some design characteristics and performance conditions of e.g. a wind tur-
bine in an isolated system in Egypt and a wind turbine situated in an offshore
wind farm in Denmark are similar, while others are quite different. Thus it is
beneficial to introduce a division of the power systems into a number of groups
or categories according to the installed power capacity.
Four groups are listed in Table 5 using the installed power as the main key.
Table 5. Categorisation of power systems.
Installed Power Category
< 1kW Micro systems
1-100kW Wind home systems
100 kW -10MW Island/Isolated systems
> 10MW Wind Power Plant systems
The installed power presented in Table 5 should be seen as indicative of the or-
der of magnitude. Thus a micro system is typically a small wind turbine with a
capacity less than 1kW; a wind home system has a typical a capacity between 1
and 100 kW with a wind turbine of 1-50 kW; an isolated power system is typi-
cally from 100 kW to 10 MW installed power and with wind turbines in the
range from 100 kW to 1 MW, while a wind power plant or a wind farm typi-
cally is larger than 10 MW with several wind turbines larger than 500 kW.
The wind penetration level of the power systems presented in Table 4 are plot-
ted in Figure 1 as a function of the installed capacity. The situation in Denmark
in 1998 and as planned for the year 2030 have been used as guiding values in
case of the very large power systems. The dashed trend line shows the degree to
which the level of wind energy penetration of actual power systems with suc-
cessful track records decreases as the power system size increases. The dotted
line indicates a possible future development towards higher penetration levels,
which may be achieved in the coming 20-30 years. The benchmark points as-
sumed for the dotted line are
• Frøya Island - a Norwegian research system aiming at maximum penetra-
tion
• Denmark in 2030 according to the official Danish energy plan
The feasibility of very high wind energy penetration is seen to change dramati-
cally in the 100kW-10MW system size range. In this range conventional elec-
tricity generation is still diesel based and cost of energy is rather high, but not
necessarily varying a lot through this range. The main reason for the dramatic
drop in wind energy penetration is that energy storage is needed to reach the
very high penetration levels and that managers of larger systems will prefer a
cautious approach, fearing negative consequences for the existing equipment
due to wind power fluctuations.
As indicated by the dotted line in Figure 1, the level of wind energy can be de-
veloped to increase significantly in the future. Thus the challenges of national
(and Trans-national) systems will be to increase penetration to levels already
14 Risø-R-1257(EN)
existing in smaller isolated systems, which themselves seem to be well placed to
increase their wind energy penetration to levels typical for just slightly smaller
systems. Obviously great care has to be taken in this process, where many fail-
ures have occurred due to over-ambitious system designs with to high degree of
complexity and too little experience as a background for the project develop-
ment. Thus, when gradually increasing the wind energy penetration starting at
the dashed line and moving towards the dotted line step-by-step applying sim-
ple, robust, reliable and well tested concepts seem to be the recommendable
approach.
The guidelines / recommendations stated later in this report are mainly associ-
ated with wind home systems and island/isolated systems in the range from 30
kW up to 10 MW installed power.
100
80
60
40
20Wind Penetration [%]%
10 100 1k 10k 100k 1M 10M 100M 1G
Installed System Power [W]
Sal
Mindelo
Dachen
Faula Island
La Desirade
Masabit
Cape Clear
Rathlin Island
Frøya Island
Denham
10G
Denmark(1998)
100G
Denmark(2030)
Today
Future
1T
Micro systems
Wind Home systems
Island/Isolated systems
Wind Power Plant systems
W
Figure 1. Present and expected future development of the wind energy penetration vs. the installed
system capacity.
Risø-R-1257(EN) 15
3 State of the Art – Economics
The economics of isolated systems with wind power is not well documented,
but a description includes the following issues:
• Cost of electricity in isolated systems
• Cost of electricity from wind turbines
• Typical electricity production costs of a WD system
Cost of electricity in isolated systems, where existing power supply is typically
from diesel power plants, varies over a very wide range:
• Low values of the order 0,20 USD/kWh
• Medium values of the order 0,45 USD/kWh
• High values of the order 1,0 USD/kWh.
Thus the cost of electricity in existing isolated systems is typically many times
higher than in large utility grids, where production cost of electricity (taxes not
considered) is of the order 0,04 USD/kWh
Cost of electricity from grid connected wind turbines has decreased from typi-
cally 0,20 USD/kWh in the early 1980’s to now approaching the production
costs of 0,04 USD/kWh in large grids. The main parameter influencing the COE
from wind turbines is the annual average wind speed.
Electricity production costs from WD systems are not well documented, and
they cover a very wide range. Furthermore COE from a WD system may be dif-
ficult to ascertain precisely, as the task may be outside the scope of small scale
DRE projects. Therefore the economic viability of a WD system will often be
assessed by comparing the COE from the wind turbine (including costs of any
support technology) with the avoided costs due to fuel saving in the existing
diesel system. In case of a retrofit installation of a wind turbine in an existing
WD system this may be a fair assessment, however, in the planning phase of a
new isolated system the comparison should be based on total cost of electricity
including capital cost of the alternatives analysed.
4 Fact Finding
4.1 Wind Resources & Climate
Knowledge of the characteristics of the climate and especially the wind regime
is crucial for the design and assessment of a potential project with a content of
wind energy. This task should comprise the following:
16 Risø-R-1257(EN)
• Identification of existing long-term measurement of wind speed and direc-
tion from a meteorological station. Data should preferably be either in time-
series format or in histogram for a period of 3-10 years.
• Assessment of quality of such data
• Extrapolation to potential application sites – by WAsP or WAsP derived
tools
• Identification of sites for additional wind measurements
• Planning and execution of dedicated wind measurements (see (B.H.Bailey
& S.L McDonald, 1997)
• Obtain maps of the area in digital and paper form. The maps should contain
both height contours and land-use (roughness) contours.
During a site visit, the roughness classification should be observed and inter-
preted based on the maps and the visual inspection.
• at the wind measurement locations and surroundings
• at potential wind farm sites and surroundings
• at existing long term meteorological stations and surroundings
For a good guide to monitoring of wind and data collection see (B.H.Bailey &
S.L McDonald, 1997).
Surroundings of sites and meteorological stations means in this respect up to 10
km from the candidate sites for wind turbines and from any meteorological sta-
tion, where the influence of roughness is significant for the results of the flow
modelling. Some useful forms for fact finding are included in appendix A.
4.2 End User Needs and Load Demand
The primary objective of the power system is to supply power in order to pro-
vide certain services for the community. The single most important task when
designing a power system is the description of the services that are required.
The list of services can be quite long however it is necessary for the assessor to
produce this list as accurately as possible. This has to be done in close collabo-
ration with the local community/authority. The list should contain both required
and desired services for immediate implementation as well as future implemen-
tation. Such a list might contain some of the services listed below:
• Domestic: Lighting, TV, refrigerator etc.
• Telecommunication: Repeaters, telephone/fax/internet
• Workshops
• Offices
• Shops
• Hotels
• Desalination plants
• Hospitals/Health clinics
• Schools
Each of the services should be characterised according to the list below
• Energy consumption
• Load profile (day, week)
• Geographical location
• Priority (primary or base, optional, deferrable load)
Risø-R-1257(EN) 17
• Seasonal influence
Having produced a list of services supplied by the power system including the
characteristics as above it is possible to aggregate the load for use in the system
analysis. Since the estimated load is to be used in both the sizing of the compo-
nents, determination of the operating strategy and for the technical/economic
analysis the important key figures are the minimum and maximum load and the
load profile. It is also important to specify the priority of the load in terms of
primary, optional and deferrable. If there are significant seasonal variations
these have to be quantified as well.
The final part of the specification of the end user need is to provide forecasts for
the load. Since improvement of the power supply often results in more people
using more energy there will typically be a relatively high growth rate in the
demand. The steep increase in the load will of course have a significant impact
of the performance of the power system, especially on the ability to supply
power even during peak load periods. The load forecast is also used in the plan-
ning of grid extensions including analysis of potential interconnection of the
isolated grid either to neighbouring grids or to a larger national grid.
The acquisition of consumer load data can be quite difficult especially if the
project is electrification. In existing power systems the only data available will
often be readings by the operator at the power station e.g. hourly and monthly
energy consumption readings. These data are valuable but are not sufficient for
a more thorough analysis of advanced operating strategies. Load forecasts can
also be estimated based on historical data. In case of electrification the load of
the system has to be entirely based on the assumed loads. In this case the sys-
tematic approach outlined above is recommended.
4.3 Existing Power Supply
In order to obtain data on the existing power supply and grid it is recommended
to prepare a questionnaire. The questionnaire should cover generation, distribu-
tion and consumption. There are many applications of the data. These include
performance characteristics (e.g. fuel consumption) for system performance
assessment, condition of the equipment (e.g. gensets and grid) in view of future
use in the system, extension plans etc. An example of a questionnaire is in-
cluded as appendix D. It can be beneficial to divide the questionnaire in order to
have a less detailed one to be used in the initial stage of the analysis and a more
detailed one to be used in the final design. Some of the points to be covered are
listed below.
• Number of consumers
• Installed capacity, No. generator units, year of commissioning and
O&M-status
• For each generating unit specify (base load/ intermediate/ peak
load/back-up)
• System operation: manual/automatic
• Diesel genset operation: maximum and minimum load, load sharing
• cosϕ at busbar
• grid-frequency and voltage stability limits and control e.g. type of
governor and AVR
• Distribution: Breakers, protection level, earthing, transformers
• Grid map: length, cross section, material, overhead lines/cables
18 Risø-R-1257(EN)
• Operational experience: typical faults, number and duration of outages,
maintenance schemes
• Fuel consumption
• Operational hours on annual basis
• Total consumption (kWh)
• Diurnal load variation
• Cost of energy, price of energy
• O&M staff, qualifications etc.
• Billing procedures
• Design codes
• Planning codes (guidelines/ manufacturers framework agreements/ etc.)
4.4 Physical Planning & Infrastructure
The possibilities and limitations imposed by the existing physical planning of
the community must be taken into account. Examples of issues to be considered
include
• Land use and building restrictions
• Development plans for the location in question (land, buildings, industry)
• Permissions needed and ownership issues
• Special protection areas
• Environmental restrictions.
The existing infrastructure and its ability to support the level of technology pro-
vided by the prospective project must be carefully assessed. Also basic issues of
access roads and load carrying abilities should be evaluated, including issues
such as:
• Site access: roads, rails, harbour
• Relevant wind turbine sites: accessibility, distance to applicable grid
• Cost-addition to fuel due to long transport distance
• Sustainability of possible wind turbine equipment: temperature and tem-
perature variations, dust, dirt.
• Access to phone, fax, e-mail.
• Accommodation facilities, for temporary construction team and permanent
O&M staff
• Shops where common spare parts and tools can be obtained
• Local presence of electronic and mechanical workshops to produce rudi-
mentary spare parts on the location and carry out emergency repairs
4.5 Development Trends
The introduction of wind power (and several other renewable energy technolo-
gies) implies that considerable investments must be made initially, which means
a long technical/economical project life time (8 – 10 years or more) in order to
obtain a reasonably low COE from the system.
Therefore it is necessary to get as much information as possible about the ex-
pected development trends for the community in question, in terms of
Risø-R-1257(EN) 19
• Technical development trends such as expected developments in power
consumption / end user needs and expected scenarios for the expansion of
power production facilities by utilities.
• Economic development trends such as expected developments in fuel and
labour cost, capital costs (interest, inflation rates) and taxes / duties.
• Private projects adding new power plants.
Additional details are offered in Section 6.6.4
5 Project Feasibility Analysis
In the feasibility phase a potential site (or a few sites) are identified for further
examination. For the analysis of the technical and economical performance of
the isolated or WD system a sketch design of the proposed system is carried out
and the scenarios to be studied are identified.
5.1 Wind Resource
Estimation of the wind energy resource potential at a given site should be done
using the Wind Atlas method (see (Risø Wind Energy Dept., 2001)). This im-
plies extrapolation of nearby representative wind statistics from a wind meas-
urement station taken at a topographically simple site for a climatologically
long enough period to the potential wind farm site.
The assessment of the wind resource and annual energy production requires
some or all the following:
• Literature, data from WMO, airports and met stations
• Existing wind turbine production statistics
• Surrounding topography - 1:25000 maps, 5-10km distance
• Assessment of existing wind data and new measurements at the potential
sites
• WAsP or a WAsP based wind resource assessment tools (see appendix B)
• Extreme winds and turbulence (from e.g. WAsP Engineering (see (J.Mann
et al., 2000))
• Candidate lay-out of wind turbines (co-ordinates of the turbines)
• Power and thrust coefficient curve(s) of the turbines, hub height and rotor
diameter of the wind turbines.
5.2 Site Selection
• In general: availability of land, human resources and infrastructure
• Adaptation to the national and local development plans and physical sur-
roundings
• Physical planning - existing and new requirements for the site and surround-
ing land
20 Risø-R-1257(EN)
• Requirements and limitations set by nearby installations - e.g. airports' obsta-
cle limits
• Electromagnetic interference - e.g. airports' ILS and radio systems, LORAN
and VOR systems, SOLAS systems, Microwave links, telecom stations,
military installations
• Climate in general - temperature, humidity, etc., and its impact on design re-
quirements e.g. regarding corrosion protection, cooling, tropicalization, pro-
tection against low temperatures etc.
• Soil conditions
• Access to site
• Erection - facilities, conditions, need for landscaping
5.3 Electrical Design
During the fact finding the relevant standards and requirements are identified as
well as existing grid codes. These standards, requirements and grid codes
should cover:
• Safety of personnel
• Quality of supply incl. security of supply, quality of voltage and frequency
(variations, distortion, flicker etc.)
• Preferred types of equipment
Using this for each of the scenarios the following is assessed:
• Voltage stability
• Frequency (angular) stability
• Steady state behaviour (load flow)
• Assessment of flicker, harmonics etc.
The analysis is carried out with due consideration to the size of the system un-
der investigation. For small systems the additional costs involved in performing
the analysis will often be prohibitive. The approach in this case could be some
kind of type approval, factory tests and track records (verified references). For
large systems the performance requirements will be more demanding and a de-
tailed analysis is required.
The electrical design should be as detailed as the technical performance is en-
sured and that cost estimates of the complete system can be done. Sketch design
of the system is a requirement both in order to be able proper performance
analysis and system costing but also in order to document various designs con-
sidered as part of the study.
The sizing of the components should include the spatial and temporal distribu-
tion of the load and generation. This information is collected as part of the fact
finding.
• Electric grid connection – standards & requirements
• Drawings and specifications of the grid components
• Load distribution in the grid - historical data and forecasts
• Sketch design of grid interconnection of wind farm
• Assessment of potential impact on power quality (applicable standards)
• Power system operation and control system communication
• Grid reinforcement versus wind power
Risø-R-1257(EN) 21
5.4 Technical Performance
The technical performance will be assessed by applying a variety of measures.
These measures include overall system performance as well as performance of
the individual components of the system. For prospective systems the determi-
nation of the performance figures will usually involve system simulations using
a variety of models each capable of simulating specific aspects of the system
behaviour. This includes screening models, logistic (power flow) models, load
flow models, dynamic models and transient models. In order to be able to cal-
culate the specified measures system operating strategies have to be specified
and implemented in the relevant models. It is also very important to specify
how the performance is verified on the installed system.
5.4.1 Performance Characteristics
By evaluation of the performance characteristics it is possible to compare the
various scenarios on system level as well as at a component level. On the sys-
tem level the most interesting measures are security of supply, total fuel con-
sumption, saved fuel as well as potential and utilised wind energy.
A range of relevant performance characteristics are listed below:
• Conventional generation
• Power production
• Running hours
• Fuel consumption
• Fuel tank capacity requirements
• Wind energy
• Potential production
• Utilized production
• Capacity factor
• Storage
• Energy in/out
• Efficiency
• Life time consumption e.g. charge cycles
• Power Quality & Grid stability
• Loss of load expectation/probability
• Loss of energy
• Voltage quality
• Frequency quality
• Supply reliability
• Production statistics
• Primary load
• Optional load
• Deferrable load
• Penetration of wind energy
• Dumped energy
As is observed from the list above the range of performance characteristics is
very wide. Some are calculated on a time scale of years and others are calcu-
22 Risø-R-1257(EN)
lated at a time scale of sub seconds. In the design and analysis phase of a project
these numbers are calculated using simulation models. Due to the very different
time scales involved as well as of the different nature of the measures separate
models have to be applied. A selection of models are listed in section 5.6.
The use of the performance characteristics is twofold. First of all, they are used
directly in the comparison between the scenarios studied. This includes charac-
teristics such as loss of load probability, voltage quality and frequency quality.
Secondly, some of the figures are used in the economic performance calcula-
tions. These are fuel consumption, utilized wind energy and expected battery
lifetime.
5.4.2 System Configuration and Operating Strategy
The system configuration and operating strategy both play an important role in
the performance of the system. The objectives of the system can be many and
include high quality power supply for communication purposes, maximum fuel
saving for environmental purposes and lowest operating cost for economic rea-
sons. The operating strategy also has a significant impact on the conditions of
the individual components of the system such as minimum load of the diesels,
charge and discharge regime of batteries and voltage variations for the load.
Many considerations have to be taken into account when designing the operat-
ing strategy. This include the desired level of automatic operation, the maturity
of the system design, the infrastructure of the community served as well as more
technical matters such as operating conditions of components and the system
objective.
5.4.3 Technical Performance Verification
A major and very difficult task is to specify procedures for the verification of
the performance of the system. The main difficulty arises from the fact that the
system performance specifications are often based on a complex set of assump-
tions. These assumptions have to be made in the design phase due to a lack of
data on the conditions in which the system will be operating.
One approach is to establish the actual operating conditions as accurately as
possible together with measurements of the main system performance measures.
The exercise is then to transform the observed system performance at the actual
conditions to the conditions specified. This can be done using the same models
as applied in the design phase of the project. It is a difficult task and the results
will often be open for interpretation. It is recommended to simplify as much as
possible the guaranteed performance data and state the proposed procedure for
performance verification at an early state in order to maintain a high level of
confidence with the project stake holders.
5.5 Economic Performance
It is necessary to distinguish between economic and financial performance.
The analysis of economic performance excludes items such as local taxes and is
used to provide the community’s decision makers with a basis for comparing
Risø-R-1257(EN) 23
the investment in the proposed project with other options, not necessarily re-
lated to energy production.
Financial analysis results, where local taxes etc. are included, are used to pro-
vide the prospective operator/developer and his financiers with a basis for a de-
cision on whether the financial returns are satisfactory and thus warrants an in-
vestment in the project.
Both types of analysis should be based on life cycle cost analyses as described
in the IEA recommended practice for estimating COE from wind turbines - see
(J.O.G Tande & R.Hunter, 1994).
In a total cost analysis the total power supply system with all installations in-
cluding wind power is considered. In this case it is possible to estimate overall
COE for the entire power production.
In an avoided cost analysis the marginal costs and benefits associated with
adding wind power to the existing power supply are considered. In this case the
costs of adding the wind turbine is compared to the benefits of replacing part of
the fuel consumption of the existing power supply system.
Both technical and economic developments in time should be considered, and if
the technical lifetime of the installed technology exceeds the economical life of
the project, the salvage value of the equipment at the end of the economic life
should be added to the income of the system.
5.5.1 Project costs
All ordinary project costs should be included in the cost analysis to be carried
over to the track record for COE of the technology. Ordinary project costs in-
clude capital costs, O&M costs etc. as outlined below.
Extraordinary project costs for the demonstration aspects of the project should
not be included in the cost analysis. Otherwise the track record of the technol-
ogy might be confused by the seed money necessary to open the market.
Investment costs
If more accurate data are not available from previous or similar projects one
should use generic data based on established practice.
Wind turbines:
• Std cost/MW installed, additional cost for arctic or other modifications
• Infrastructure: Standard add-on (30%) unless specified
Diesel generators:
• Std cost/MW installed, additional cost for arctic, tropical, high altitude etc.
• Infrastructure: Standard add-on (30%) unless specified
Auxiliary equipment :
• Dump load
• Devices for optional/deferrable production (pump, heat, cool, freeze, other)
• Devices for energy storage (batteries, flywheel, pumped storage, other)
• Transportation of equipment
24 Risø-R-1257(EN)
• Erection of equipment
• Training
Running costs
The two major operating costs for the diesel generators are
• Fuel cost. A typical specific fuel oil consumption for small diesel generat-
ing sets at high loads is 200 - 250 g/kWh produced (at LHV of 42,7 MJ/kg).
For a WD system the diesel generator is often running at low load (<50%)
and it is more relevant to consider the fuel consumption as a flow rate (l/h),
which is nearly constant at low load. When estimating the fuel cost care
should be taken to use the cost delivered at the site and including all appli-
cable taxes.
• Cost of lubricating oil. A typical consumption of lubrication oil is 1-3
g/kWh.
O&M costs
Operating and maintenance costs comprise manpower for operation and main-
tenance as well as spare parts. Use typical data from similar projects or manu-
facturers or use generic data based on established practice.
• Wind turbines: Percentage of wind turbine investment per year or cost per
kWh produced
• Diesel generators: Percentage / fixed cost per operational hour or cost per
kWh produced
• Auxiliary equipment by type (e.g. life time / replacement for batteries)
Retrofit & salvage costs
In general it is recommended to use data from previous or similar projects oth-
erwise one should use generic data based on established practices for
• Wind turbines
• Diesel generators
• Auxiliary equipment (determination of lifetime and replacement frequency
for battery storage)
• Other costs
Extraordinary project costs
The extraordinary costs are project costs that are to be covered for a pilot /
demo system but should not enter the track record because they are not part of
the regular expenses. Extraordinary costs include:
• Engineering support
• Consultancy & supervision
• Planning support
• Project & system monitoring
• Evaluation & reporting
Risø-R-1257(EN) 25
5.5.2 Cost of Energy, COE
The COE should be calculated based on a life cycle cost analysis along the
lines of the IEA Recommended Practice for COE from grid connected wind
turbines ((J.O.G Tande & R.Hunter, 1994)). Items include
• Financial vs. economic COE
• Discount rate(s)
• Capital costs
• O&M Costs
• Retrofit Costs
• Salvage value
• Levellised COE
5.5.3 Value of Energy, VOE
The VOE is input to a Life Cycle Cost analysis of return on the investment in
the project and the operation of the system. Items include
• Baseline scenario for existing power supply
• Cost & price structures, subsidies
• Tariffs, PPA for sales of electricity
• Fuel costs, total & avoided by adding the equipment of the project
• Externalities i.e. incremental costs related to e.g. greenhouse gas abatement
Primary power supply
Primary power supply denotes consumer loads that must (in principle) always
be met upon demand. It is characterised by
• VOE according to existing tariffs / PPA
• Industry and household electricity demands
• Street lights and other public demands
• Base loads for e.g. water pumping, desalination, heating, cooling etc.
Optional loads
Optional power supply denotes consumer loads that can be met if and when
power is available after the primary load demand is met. It is characterised by
• Utilisation of dump load power for e.g. water pumping, desalination, heat-
ing, cooling etc.
• VOE is typically lower than primary power and should be estimated if not
included in the tariffs or PPA
Deferrable loads
Deferrable power supply denotes consumer loads that must be met within a
certain span of time but may be met if & when power is available after primary
load demand is met. It is characterised by
• Utilisation of dump load power for e.g. water pumping, desalination, heat-
ing, cooling etc.
• VOE is typically lower than primary power and should be estimated if not
included in tariffs or PPA
• If deferrable loads are not met within a certain time span they become pri-
mary loads
26 Risø-R-1257(EN)
Externalities
Externalities are the term often used for the values that are associated with re-
newable energy production but not accounted for in the traditional economic
analysis. They include
• Reductions in greenhouse gas emissions. Values are assigned on a na-
tional/regional/global level.
• Reduction of harmful air borne emissions e.g. NOx, SO2 and particulate
emissions. Values are assigned on a regional/local level.
• Reductions in fuel and oil spillage. Values are assigned on a local level
• Reductions in noise levels and other disturbances. Values are assigned on a
local level
Externalities can only be included in the assessment of operational economy if
they are actually paid for by customers. Externalities may be used to obtain part
of the investments on favourable conditions, e.g. from GEF on a global level or
by governments on a national level, and in such cases externalities can be in-
cluded in the assessment of the operational economy of the project.
5.5.4 Development Scenarios
The technical-economical project life associated with implementing wind en-
ergy into an isolated power supply system will be many years, frequently up to
20 years. Therefore, the scenario to be analysed should include a development
scenario that represents the assumed development in both technical and eco-
nomical/financial terms.
Technical development includes the development of parameters such as
• Consumer demand in terms of primary and secondary load types
• Generating capacity in terms of e.g. active diesels and their replacements /
extensions
• O&M needs as generating capacity ages and expands
• Operating strategy and priorities
Economical development includes the development of parameters such as
• Consumer rates and tariffs
• Fuel costs and prices
• O&M costs as existing generating capacity ages and new capacity is added
• Major repairs / overhaul / retrofit
Financial development includes the development of parameters such as
• Inflation
• Interest rates
• Taxes, duties and deductions
Ideally the development scenario should be represented by tables specifying the
assumed values of the above parameters year by year during the entire project
life. The technical-economical models used should be able to utilise this infor-
mation in a life cycle cost analysis.
Risø-R-1257(EN) 27
5.5.5 Assessment of Results
The results of the economic/financial analyses come in the form of annual cash
flows specifying the projected expenses and income from the installation and
operation of the project. The economic/financial indicators used to assess the
results include
• Levelised production cost, LPC (cost/kWh) of wind energy,
• Sort run marginal cost, SRMC (cost/kWh) - with and without the assessed
wind power plant.
• Net present value, NPV of the project
• Economic internal rate of return, EIRR (% p.a.) of the project
• Financial internal rate of return FIRR (% p.a.) of the project
• Return on Equity ROE (% p.a.) for the investor
• Simple payback time (years) of the project
• Cost of alternative technologies (relevant for the case considered) e.g. solar,
hydro etc.
The results will be assessed by comparing the economic/financial indicators
with the criteria / threshold values applied by the investor/financier/donor in
question for the project.
5.6 Modelling & Simulation
The technical and economical performance of prospective systems is analysed
by computer simulation of the systems, and several types of models are used
depending on the characteristics on which the simulation is focused. The main
parameter characterising the models is the time scale of the simulation, and we
usually distinguish between the following types:
• Screening models give an overall assessment of the performance of the
system, without going into very much detail of the specifics in the operation
of the system.
• Logistic models focus on predicting the annual power productions, fuel
savings and power flows in the system. Logistic models are usually the ba-
sis in screening models, and they may be deterministic time series models
or probabilistic models that produce probability distributions.
• Dispatch models focus on the dispatch of the various power producing
components of the system, i.e. start/stop of diesels etc. Time scale typically
minutes to an hour.
• Dynamic models focus on the electromechanical behaviour of the system,
i.e. machine dynamics but not electrical switching may be represented.
Time scale typical a few seconds to half an hour.
• Transient models focus on electrical transients including switching. Time
scale typically seconds to minutes.
System control models focus on a representation of control strategies of the
system, or parts of the system. Dispatch type models are usually the basis for
system control models.
A number of numerical modelling techniques and models are available for the
assessment of technical-economic performance the system. Risø R-1109 pres-
ents a review of models, and selected models from the review are briefly de-
scribed below:
28 Risø-R-1257(EN)
HOMER is a fast & comprehensive village power systems screening model,
now (1998) supplemented with the VIPOR model for optimal layout of a supply
area into grid connected vs. independently supplied consumers. State of the art
in this category, but not publicly available. (P.Lilienthal et al., 1995)
INSEL Offers almost unlimited flexibility in specifying system configurations
by allowing the user to specify the connectivity on a component level. Intended
as an out-of-house-model. (Renewable Energy Group, 1993)
HYBRID2 The state-of-the-art (1998) time series model for prediction of tech-
nical-economical performance of hybrid wind/PV systems. Offers a very high
flexibility in specifying the connectivity of systems. Publicly available and quite
widely used. (H.J.Green & J.Manwell, 1995)
SIMENERG The only model so far with a very high degree of flexibility in the
control / dispatch strategy, using a “market square” approach, where the eco-
nomically optimal subset of power sources that satisfy the power demand is
dispatched in each time step. (C.Briozzo et al., 1996)
WINSYS is a spreadsheet (QPW) based model implementing probabilistic rep-
resentations of resources and demands. WINSYS incorporates the anticipated
technical expansions during its lifetime in the technical performance measures,
combined with a traditional economic life cycle cost assessment. Thus
WINSYS represents a more real life cycle cost analysis than most other models.
It is not commercially available. (J.C.Hansen & J.O.G.Tande, 1994)
ENGINEERING DESIGN TOOLS FOR WIND DIESEL SYSTEMS, This
package contains seven European logistic models: SOMES (NL), VINDEC (N),
WDILOG (DK), RALMOD (UK) and TKKMOD (FIN). It also includes the
modular electromechanical model JODYMOD. (D.Infield, 1994)
PROLOAD A probabilistic load flow analysis code, using Monte Carlo tech-
niques, developed in co-operation with an electrical utility for dimensioning of
distribution systems with wind turbines. (J.O.G.Tande et.al., 1999)
RETScreen is a spreadsheet (Microsoft Excel) based analysis and evaluation
tool for assessment of the cost-effectiveness of potential projects with renew-
able energy technologies. The software package consists of a series of work-
sheets with a standardised layout as well as an online manual and a weather and
cost database. The tool is developed by the CANMET Energy Diversification
Research Laboratory (CEDRL) and is available from the Website of CEDRL.
(CEDRL, 2000)
5.7 Uncertainties and Sensitivity Analysis
As the modelling techniques used imply (often considerable) uncertainties the
results should not be taken as an accurate representation of the reality of the
future. They should rather be taken as one possible manifestation, and they
should be supplemented by an analysis of the impact of the major uncertainties.
The most important types of uncertainties are
• Modelling uncertainties
• Input data uncertainties
• Parameter uncertainties
The sensitivity to changes in assumptions and input data is usually ascertained
by running the models a number of times, where each time one parameter is
changed while the other are kept constant. This way the sensitivity of results to
variations in the assumptions is estimated, and this is a very important aspect of
Risø-R-1257(EN) 29
the analyses. The results of a sensitivity analysis is usually presented in so-
called spider diagrams
5.8 Environmental Scoping
At the same time as carrying out technical and economical analyses, developers
should also consider the environmental acceptability of potential sites. The ini-
tial environmental acceptability considerations (commonly known as environ-
mental scooping) will mainly be based on studies of existing data. A review of
reports, equipment performance specifications and maps of the area should be
carried out in order to determine specific technical or environmental issues, de-
velopers should be aware of considering existing and emerging national, re-
gional and local planning policies.
The following issues should be addressed at a preliminary level, each of which
will be studied in greater detail in subsequent phases of the project develop-
ment:
• Visual Impact
• Proximity to dwellings (existing and planned)
• Ambient air quality
• Noise
• Sensitive Ecology /rare or endangered species
• Archaeological / historical heritage
• Areas for Recreational use /national parks / reserves
• Interference with telecommunications
• Planning issues e.g. civil and military airports
Scoping document
The scooping phase will briefly review the data already available and identify
the environmental issues that will have to be subsequently reviewed in detail.
The results are normally summarised in a scooping document or report.
30 Risø-R-1257(EN)
6 Environmental Impact Analysis
In projects, where it is likely that the proposed project will have significant ef-
fects on the environment by virtue of factors such as its nature, size or location,
it may require a more detailed environmental impact analysis.
A full and comprehensive environmental impact assessment consist of an analy-
sis of the following:
• Policy and legislation framework
• Plant design documented in a project description with emphasis on envi-
ronmental impact
• Analysis of present or baseline situation (emphasize what is particularly
sensitive)
• Environmental impact assessment (Construction phase)
• Environmental impact assessment (Operation phase)
• Analysis of alternatives
• Describe mitigation measures to decrease the environmental impact
• Outline of monitoring in the construction and operation phase.
• Public Consultations
The list of contents above is generally accepted as the basis of a full environ-
mental assessment of a project and is widely used internationally among others
by the World Bank and other financial institutions as well as consultants. For
reference see the World Bank /IFC Operational Procedure for environmental
assessment included in appendix C. In case of large projects it is recommended
to follow the full environmental review procedure outlined above, while for
small projects and /or projects with a limited impact on the existing environ-
ment a reduced scope can be applied. In many such cases the environmental
scoping report will be sufficient to satisfy the needs of the stakeholders of the
project including the local authorities and the financing body.
The following topics are considered in the environmental analysis:
• Site selection
• Ambient air quality
• Visual and landscape assessment
• Noise assessment
• Assessment of flora and fauna
• Archaeological and historical heritage
• Hydrological assessment
• Interference with telecommunication systems
• Aircraft safety
• Safety assessment
• Traffic management and construction of access roads
• Landscaping and deposit of waste during the construction
• Socio-economic effects
Risø-R-1257(EN) 31
In particular for the main components of the WD plant:
6.1 Diesel Generating Set
• Exhaust Gas Emissions: NOx SO2 and particulate matter
• Global warning effects from CO2
• Noise emission
• Risk of fuel spills
• Disposal of used lubrication oil
6.2 Wind Turbines
• Visual impact
• Noise emission
• Shadows and blinks
• Impact on flora and fauna - e.g. danger for rare species, migrating birds
• Impact on reservation areas, archaeological sites or other special interests
• Probability and consequences of accidents to humans or nature
6.3 Desalination
• Impact of raw water supply on level of aquifer or marine life
• Disposal of conc. and warm brine
• Use of additives to control of scale formation and biocides to prevent or-
ganic growth
• Impact on drinking water quality and health aspects
6.4 Battery Storage
• Risk of leaks
• Expected lifetime and disposal after use
6.5 Socio-economic and Sociological Issues
Socio-economic and sociological issues are often neglected in the evaluation of
viability of a project. This is due to the fact that the items related to the socio-
economic and sociological issues can be difficult to assess and moreover it can
be quite difficult to prescribe/estimate a fair price/cost of these items. An im-
portant example is environmental externalities.
Nevertheless, evaluation of socio-economic and sociological issues should be
quantified and analysed as much as possible. The keywords are identification
and quantification of relevant issues. In general terms the methodology there-
fore comprises two tasks:
1) identify and assess the benefits of rural electrification.
2) quantify the costs of rural electrification.
32 Risø-R-1257(EN)
Examples of socio-economic and sociological issues to be considered are listed
below. What is the impact:
• on economic growth.
• on agricultural production and rural industrialisation.
• on the unemployment rate
• on the quality of rural life.
• on incomes and poverty alleviation.
• on migration and birth rates.
• on the environment.
Based on these findings a comparison of benefits and costs can be performed –
preferably both on a monetary and a non-monetary manner. The monetary part
should of course be added to the economic analysis as project costs. See e.g.
(F.Fluitman, 1983) and (World Bank Group, 1998)
7 Institutional and Legal Framework
The importance of institutional issues is illustrated by the fact that it has fre-
quently been demonstrated that technically feasible but institutionally problem-
atic projects will not work. These issues should be paid a proper attention by
project developers. Institutional issues denote a range of non-technical issues
that are outlined in this section.
7.1 Legal Issues
It is necessary to clarify which (if any) legal framework exists for the utilisation
of wind energy in the prospective case of isolated power supply. Issues include:
• Policies & incentives for wind energy
• Rights & conditions to build/erect/install wind energy equipment
• Rights & conditions to connect to busbar / grid / substation
• How and by whom are the policies, incentives, rights and conditions deter-
mined?
• Which standards & regulations apply?
7.2 Ownership and Responsibilities
The ownership of the project and subsequent the plant should be clearly de-
fined. Is the owner a
• Utility
• IPP organised as Ltd.
• Co-operative
• BOO/ BOOT scheme
On the rights and obligations of the ownership:
• Rights to connect to the grid and produce power
• Agreements on how to get revenues (PPA)
• Obligation or right to produce/repair/remove/replace/expand
Risø-R-1257(EN) 33
In a project with multiple partners a clear definition of the responsibilities in the
development, construction and operation phase of the project is vital for a good
progress of the project.
7.3 Stakeholders
The parties with an interest in the project should be identified as well as the na-
ture of their interest
• Community council / local authorities
• Regional / governmental authorities
• Power supply responsible / companies / utilities
• Consumers / consumer groups / consumers with special needs
• Experts / expert groups / associations / knowledge centres
• Industry / manufacturers (local vs. regional / national)
• Neighbours
Outline the structure of interests and try to identify possible conflicts of interest
that could jeopardise or delay the project
7.4 Technology Carriers
Identification of parties with a capability to participate in the necessary technol-
ogy transfer and to make the technology available to the community in question
(region / nation). It should be considered how to involve such parties in the
project. Potential parties are
• Power supply entities
• Private industry
• Service organisations
• Government agencies
• Universities
7.5 Sustainability / replication
The sustainability and replication potential of the project should be assessed
based on institutional issues as well as findings from technical, economical, and
market & policy issues.
8 Financing
Before the project sponsor or developer approach a potential investor or a
funding agency e.g. a bank or an aid organisation it is recommended to consider
the following:
• Prepare a project outline description
• Proposed time schedule for implementation
• Project investment including breakdown in major items
• Relevant economical and financial key figures or indicators for the project
34 Risø-R-1257(EN)
• A draft PPA or other evidence of potential income
• Cost of land (if applicable) and access right / roads
• Environmental scoping report / statement
The sources of project financing are
• Traditional private national sources
• Traditional private international sources
• World Bank / IFC, GEF, PCF
• Other multilateral organisations: Inter-American Development Bank, Asian
Development Bank, African Development Bank etc.
• National aid organisations e.g. DANIDA
• Private non-governmental organisations
9 Implementation
An important issue is to select a suitable scheme for implementation of the proj-
ect. An essential issue is to maintain a clear definition of the responsibility
throughout the design, transportation of components, erection and commis-
sioning of the plant. Subsequently in the operation phase it should be clarified
which party has the capability to operate, maintain and monitor the plant.
Monitoring and reporting including development and assessment of operation
patterns is of utmost importance for the further development of isolated power
systems.
• Implementation Schemes (turnkey, BOOT, etc.)
• Engineering design of WD Plant
• Identification of local specialists
• Assessment of the need for Ex-pats
• Logistics of spare parts, fuel and lubrication oil
• Establishment of an O&M organisation
• Monitoring and reporting
10 Conclusion and Recommenda-
tions
A number of issues have been identified which should be considered when de-
veloping a wind power project in an isolated power system. The main charac-
teristics of a successful project may be summarised as follows:
• The use of updated versions of relevant international standards – including
the one for decentralised power systems with renewable energies now in
progress within the IEC.
• That best practice guidelines for project implementation are applied includ-
ing common references and relevant experience from recent projects.
Risø-R-1257(EN) 35
• That the wind power project in the isolated system in question is part of a
concerted action in a national and international programme rather than an in-
dividual project.
• That the wind power technology applied in a small to medium size system
follow simple and proven approaches, e.g. by repeating and/or downscaling
pilot and demonstration systems with positive track records, which may have
been developed from filtering down from large-scale systems any techno-
logical achievements adaptable to smaller systems.
• That small systems are developed and specified to apply rugged technology
suitable for remote communities.
• That no experimental systems are installed at rural remote communities un-
less previously thoroughly tested and documented at test benches dedicated
to serve as experimental facilities
• That ownership is well defined with a built-in interest identified to ensure
long-term interest and funding of operation, maintenance and re-investments
when needed.
• That an organisation is established with the necessary capacity and capabili-
ty for implementation, operation and maintenance, preferably including the
back-up from a relevant national or regional knowledge centre.
• That a sufficiently detailed feasibility study has been performed.
• That modelling assumptions, input data and methodology applied for the
feasibility study and system design reflect the true hardware reality for the
types of systems in question
The technical capacity to design, build and operate isolated power systems with
a high penetration of wind power exists, but the mature product and the market
have not yet met. Nevertheless, there is today an industry offering small wind
turbines (10 - 300kW) for hybrid system applications with a long-term com-
mitment in this business. This indicates their belief that a market is emerging so
that interest also from some of the large wind turbine manufacturers can be ex-
pected.
The above recommendations are seen as moves that would all lead in the direc-
tion of a development of the use of wind power in isolated power systems. This
will open up and extend access to electricity for the benefit of the development
of small rural communities.
36 Risø-R-1257(EN)
References
A.L.Pereira. (2000). Modular Supervisory Controller for Hybrid Power
Systems.
B.H.Bailey, & S.L McDonald,A.S. (1997). Wind Resource Assessment
Handbook. NREL Golden CO.
C.Briozzo, G.Casaravilla, R.Chaer, & J.P.Oliver. (1996). SIMENERG: The
Design of Autonomous Systems pp. 2070-2073. In WREC.
RETSCREEN Pre-feasibility Analysis Software: www.retscreen.gc.ca
[Computer Software]. (2000). CANMET Energy Diversification Re-
search Laboratory (CEDRL).CEDRL.
D.Infield. (1994). Engineering Design Tools for Wind Diesel Systems. En-
ergy Research Unit, Rutherford Appleton Laboratory.
EDF. (1997). Specifications for the Use of Renewable Energies in Rural
Decentralised Electrification. Electricite De France. IEC/PAS 62111
ver 1.0.
F.Fluitman. (1983). The Socio-Economic Impact of Rural Electrification on
Developing Countries: A Review of Experience. In World Employment
Programme Reaseach Working Paper: Vol. WEP 2022/wp126. ILO.
H.J.Green,& J.Manwell. (1995). HYBRID2 - A Versatile Model of the Per-
formance of Hybrid Power Systems pp. 437-446. In Vol. Wind-
power'95 Proceedings of AWEA.
J.C.Hansen,& J.O.G.Tande. (1994). High Wind Energy Penetration Systems
Planning. In EUWEC'94 Thessaloniki, Greece.
J.Mann, P Astrup, L.Kristensen, O.Rathmann, P.H.Madsen, & D.Heathfield.
(2000). WAsP Engineering DK. Risø National Laboratory: R-1179
(EN).
J.O.G Tande, & R.Hunter. (1994). IEA Recommended Practices for Wind
Turbine Testing and Evaluation: 2. Estimation of Cost of Energy from
Wind Energy Conversion Systems. Risø National Laboratory, Den-
mark and NEL, United Kingdom.
J.O.G.Tande et.al. (1999). Power Quality and Grid Connection of Wind
Turbines. Part 1: Stationary Voltages.
L.H.Hansen, L.Helle, F.Blaabjerg, E.Richie, S.Munk-Nielsen, H.Bindner,
P.Sørensen, & B.Bak-Jensen. (2001). Conceptual Survey of Generators
and Power Electronics for Wind Turbines. Risø National Laboratory:
Risø R-1205 (EN).
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P.Lilienthal, L.Flowers, & C.Rossmann. (1995). HOMER: The Hybrid Op-
timization Model for Electric Renewable. pp 475-480. In Vol. Wind-
power '95 -Proceedings AWEA.
Renewable Energy Group. (1993). INSEL Reference Manual. (version 4.80
ed.). Dept. of Physics, Univ of Oldenburg.
Risø Wind Energy Dept. Wind Atlas Analysis and Application Program
(WAsP). Internet . 2001. Risø National Laboratory. (GENERIC)
Ref Type: Electronic Citation.
World Bank Group. (1998, July). Pollution Prevention and Abatement
Handbook: The Effects of Pollution on Health: The Economic Toll.
Washington DC.
38 Risø-R-1257(EN)
Appendix A Tables and Forms for
Fact Finding
Risø-R-1257(EN)39
WAsP Site Description Form
Name of site/station:
Visited by: Date:
Geographical reference
Latitude: Longitude:
Map sheet: Magnetic declination:
Anemometer set-up
Anemometer height: m a.g.l. Type/make:
Mast type/Ø: Averaging period: min.
Boom direction: Boom length:
Map reference
Map projection: Map datum:
Site X: m Site Y: m Site Z: m a.s.l.
Site/station visit check list
Anemometer height verified
Station history investigated
Data acquisition system check
Sector photos: 8 or 12 sectors
Mast and instrument photographs
DAS clock check, offset:
Additional information
Risø-R-1257(EN)40
WAsP Data Description Form
Name of met. station:
Prepared by: Date:
Data file reference
File name: Data period:
# of observations: Data recovery rate: pct.
Data format: Columns for U and D :
Wind speed data
Observation interval: min. Averaging period: min.
Calm threshold: Calm indication:
Discretisation: Missing data flag:
Wind direction data
Relative to geographic north Relative to magnetic north
Observation interval: min. Averaging period: min.
Calm threshold: Calm indication:
Discretisation: Missing data flag:
Additional information
Risø-R-1257(EN)41
WAsP Obstacle Description Form
Name of site:
Visited by: Date:
#α1 R1 α2 R2 HdPComments
Note: α1 and α2 are given in degrees clockwise from north and R1, R2 , h and d in metres.
Risø-R-1257(EN)42
WAsP Roughness Description Form
Name of site:
Visited by: Date:
#Dz01 X1 z02 X2 z03 Comments
1 000
2 030
3 060
4 090
5 120
6 150
7 180
8 210
9 240
10 270
11 300
12 330
Note: z0 and X are given in metres. Roughness descriptions may also be given as map data.
Additional information
Risø-R-1257(EN) 43
Appendix B WAsP
Risø-R-1257(EN)44
What is WAsP?
WAsP is a PC-program for the vertical and horizontal extrapolation of wind data. It contains several
models to describe the wind flow over different terrains and close to sheltering obstacles. WAsP
consists of five main calculation blocks:
Analysis of raw data. This option enables an analysis of any time-series of wind measurements to
provide a statistical summary of the observed, site-specific wind climate. This block is implemented in
a separate tool, the OWC Wizard.
Generation of wind atlas data. Analysed wind data can be converted into wind atlas data sets. In a
wind atlas data set the wind observations have been 'cleaned' with respect to site-specific conditions.
The wind atlas data sets are site-independent and the wind distributions have been reduced to
standard conditions.
Wind climate estimation. Using a wind atlas data set calculated by WAsP or one obtained from
another source – e.g. the European Wind Atlas – the program can estimate the wind climate at any
specific point by performing the inverse calculation as is used to generate a wind atlas. By introducing
descriptions of the terrain around the predicted site, the models can predict the actual, expected wind
climate at this site.
Estimation of wind power potential. The total energy content of the mean wind is also calculated
by WAsP. Furthermore, an estimate of the actual, annual mean energy production of a wind turbine
can be obtained by providing WAsP with the power curve of the wind turbine in question.
Calculation of wind farm production. Given the thrust coefficient curve of the wind turbine and the
wind farm layout, WAsP can finally estimate the wake losses for each turbine in the farm and thereby
the net annual energy production of each wind turbine and of the entire farm, i.e. the gross
production minus the wake losses. The program thus contains analysis and application parts, which
may be summarised in the following way: The WAsP models and the wind atlas methodology are
described in more detail in the European Wind Atlas.
Analysis
time-series of wind speed and direction —> wind statistics
wind statistics + site description —> wind atlas data sets
Application
wind atlas data + site description —> estimated wind climate
estimated wind climate + power curve —> estimated power production
Wind farm production
est. power productions + wind turbine and farm characteristics —> gross and net annual
energy production of each turbine and of wind farm
Risø-R-1257(EN) 45
Appendix C Environmental As-
sessment
Environmental Assessment (OP 4.01, October 1998)Page 1 of 12
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Note: OP 4.01 replaces the policy elements of IFC’s Environmental
Analysis and Review of International Finance Corporation Projects
(Washington, D.C.: IFC, 1993). IFC’s Procedure for Environmental and
Social Review went into effect as of September 1, 1998. Instructions to staff
on public consultation and disclosure are contained in IFC’s Policy on
Disclosure of Information (Washington, D.C.: IFC, 1997). Additional
information related to this OP is provided in the Environmental Assessment
Sourcebook (Washington, D.C.: World Bank, 1991) and subsequent
updates available from the Environment Sector Board and in the Pollution
Prevention and Abatement Handbook. Other IFC policies that relate to the
environment include OP 4.04, Natural Habitats; OP 4.09, Pest
Management; OP 4.10, Indigenous Peoples (forthcoming); OP 4.11,
Safeguarding Cultural Property in IFC-Financed Projects (forthcoming); OP
4.12, Involuntary Resettlement (forthcoming); OP 4.36, Forestry; OP 4.37,
Safety of Dams (forthcoming), and OP 7.50, Projects on International
Waterways.
Questions may be addressed to the Associate Director, IFC’s Environment
and Social Development Department. Additional copies are available to IFC
staff in the Information Resources Center, Room L-124.
Environmental Assessment
1. IFC1 requires environmental assessment (EA) of projects proposed for
IFC financing to help ensure that they are environmentally sound and
sustainable, and thus to improve decision making.
2. EA is a process whose breadth, depth, and type of analysis depend on
the nature, scale, and potential environmental impact of the proposed
project. EA evaluates a project's potential environmental risks and impacts
in its area of influence; 2 examines project alternatives; identifies ways of
improving project selection, siting, planning, design, and implementation by
preventing, minimizing, mitigating, or compensating for adverse
environmental impacts and enhancing positive impacts; and includes the
process of mitigating and managing adverse environmental impacts
throughout project implementation. IFC favors preventive measures over
mitigatory or compensatory measures, whenever feasible.
3. EA takes into account the natural environment (air, water, and land);
human health and safety; and social aspects (involuntary resettlement,
indigenous peoples and cultural property); 3 and transboundary and global
environmental aspects4 . EA considers natural and social aspects in an
integrated way. It also takes into account the variations in project and
country conditions; the findings of country environmental studies; national
environmental action plans; the country's overall policy framework and
national legislation; the project sponsor’s capabilities related to the
environment and social aspects, and obligations of the country, pertaining
to project activities, under relevant international environmental treaties and
Arabic Chinese French Spanish Portuguese Russian
Environmental Assessment (OP 4.01, October 1998) Page 2 of 12
http://www.ifc.org/enviro/EnvSoc/Safeguard/EA/ea.htm 25-06-01
agreements. IFC does not finance project activities that would contravene such country obligations, as identified during the EA. EA is initiated as early as possible in project processing and is integrated closely with the
economic, financial, institutional, social, and technical analyses of a
proposed project.
4. The project sponsor is responsible for carrying out the EA. For Category
A projects5 the project sponsor retains independent EA experts not affiliated
with the project to carry out the EA.6 For Category A projects that are highly
risky or contentious or that involve serious and multidimensional
environmental concerns, the project sponsor should normally also engage
an advisory panel of independent, internationally recognized environmental
specialists to advise on all aspects of the project relevant to the EA.7 The
role of the advisory panel depends on the degree to which project
preparation has progressed, and on the extent and quality of any EA work
completed, at the time IFC begins to consider the project.
5. IFC advises the project sponsor on IFC's EA requirements. IFC reviews
the findings and recommendations of the EA to determine whether they
provide an adequate basis for processing the project for IFC financing.
When the project sponsor has completed or partially completed EA work
prior to IFC's involvement in a project, IFC reviews the EA to ensure its
consistency with this policy. IFC may, if appropriate, require additional EA
work, including public consultation and disclosure.
6. The Pollution Prevention and Abatement Handbook describes pollution
prevention and abatement measures and emission levels that are normally
acceptable to IFC. However, taking into account country legislation and
local conditions, the EA may recommend alternative emission levels and
approaches to pollution prevention and abatement for the project. The EA
report must provide full and detailed justification for the levels and
approaches chosen for the particular project or site.
EA Instruments
7. Depending on the project, a range of instruments can be used to satisfy
IFC’s EA requirement: environmental impact assessment (EIA),
environmental audit, hazard or risk assessment, and environmental action
plan (EAP).8 EA applies one or more of these instruments, or elements of
them, as appropriate.
Environmental Screening
8. IFC undertakes environmental screening of each proposed operation to
determine the appropriate extent and type of EA. IFC classifies the
proposed project into one of four categories, depending on the type,
location, sensitivity, and scale of the project and the nature and magnitude
of its potential environmental impacts.
(a) Category A: A proposed project is classified as Category A if it is likely
to have significant adverse environmental impacts that are sensitive,9
diverse, or unprecedented. These impacts may affect an area broader than
the sites or facilities subject to physical works. EA for a Category A project
examines the project's potential negative and positive environmental
impacts, compares them with those of feasible alternatives (including, the
“without project” situation), and recommends any measures needed to
prevent, minimize, mitigate, or compensate for adverse impacts and
improve environmental performance. For a Category A project, the project
sponsor is responsible for preparing a report, normally an EIA that includes,
as necessary, elements of the other instruments referred to in para 7.
(b) Category B : A proposed project is classified as Category B if its
Environmental Assessment (OP 4.01, October 1998) Page 3 of 12
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potential adverse environmental impacts on human populations or environmentally important areas—including wetlands, forests, grasslands, and other natural habitats—are less adverse than those of Category A
projects. These impacts are site-specific; few if any of them are irreversible;
and in most cases mitigatory measures can be designed more readily than
for Category A projects. The scope of EA for a Category B project may vary
from project to project, but it is narrower than that of Category A EA. Like
Category A EA, it examines the project's potential negative and positive
environmental impacts and recommends any measures needed to prevent,
minimize, mitigate, or compensate for adverse impacts and improve
environmental performance. The findings and results of Category B EA are
described in the Environmental Review Summary, which is prepared by IFC
10
(c) Category C: A proposed project is classified as Category C if it is likely
to have minimal or no adverse environmental impacts.
Beyond screening, no further EA action is required for a Category C project.
(d) Category FI: A proposed project is classified as Category FI if it involves
investment of IFC funds through a financial intermediary, in subprojects that
may result in adverse environmental impacts. In addition, in some capital
markets projects, IFC funds are not targeted to specific subprojects (e.g.
equity in a financial institution such as a commercial bank), but the financial
institution has operations which may have adverse environmental impacts
(e.g. project finance). In such cases, IFC may also classify the project as
Category FI.
EA for Special Project Types
Financial Intermediary Lending
9. For a financial intermediary (FI) operation targeting specific subprojects,
IFC requires that each FI screen proposed subprojects and ensure that
subproject sponsors carry out appropriate EA for each subproject. Before
approving a subproject, the FI verifies (through its own staff, outside
experts, or existing environmental institutions) that the subproject meets the
environmental requirements of appropriate national and local authorities
and is consistent with this OP and other applicable environmental policies
of IFC.11 When IFC funds are not targeted to specific subprojects (e.g.
equity in a financial institution such as a commercial bank) but the financial
institution has operations which may have adverse environmental impacts,
IFC will require the FI to receive training on environmental management, if
necessary. In addition, IFC requires that investments under the relevant
operations comply with host country environmental, health and safety
requirements; no further environmental requirements would normally be
applied to these operations.
10. In appraising a proposed FI investment by IFC, IFC reviews the
adequacy of the proposed FI’s EA arrangements for subprojects, including
the mechanisms and responsibilities for environmental screening and
review of EA results. When necessary, IFC ensures that the project
includes components to strengthen such EA arrangements. For FI
operations expected to have Category A subprojects, during appraisal IFC
examines the FI’s institutional capacity for its subproject EA work and
identifies, as necessary, measures to strengthen capacity. If IFC is not
satisfied that adequate capacity exists for carrying out EA, all Category A
subprojects and, as appropriate, Category B subprojects—including EA
reports—are subject to prior review and approval by IFC.12
Institutional Capacity
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11. When the project sponsor has inadequate environmental capacity to carry out key EA-related functions (such as review of EA, environmental
monitoring, inspections, or management of mitigation measures) for a
proposed project, IFC requires the project sponsor to strengthen internal
staff capacity or retain qualified outside expertise.
Public Consultation
12. For all Category A projects and as appropriate for Category B projects
during the EA process, the project sponsor consults project-affected groups
and local nongovernmental organizations (NGOs) about the project's
environmental aspects and takes their views into account. The project
sponsor initiates such consultations as early as possible. For Category A
projects, the project sponsor consults these groups at least twice: (a)
shortly after environmental screening and before the terms of reference for
the EA are finalized, and (b) once a draft EA report is prepared. In addition,
the project sponsor consults with such groups throughout project
implementation, as necessary to address EA related issues that affect
them. 13
13. In those cases where the Category A EA has been completed prior to
IFC involvement in a project, IFC reviews the public consultation and
disclosure carried out by the project sponsor during and after EA
preparation. If necessary IFC and the project sponsor then agree on a
supplemental public consultation and disclosure program to address any
deficiencies identified by IFC. On completion of the supplemental program
the project sponsor prepares a report detailing the results of the full public
consultation and disclosure program. The Category A EA will only be made
available to the World Bank’s InfoShop once this report is complete.
Disclosure
14. For meaningful consultations between the project sponsor and project-
affected groups and local NGOs on all Category A and as appropriate for
Category B projects, the project sponsor provides relevant material in a
timely manner prior to consultation and in a form and language that are
understandable and accessible to the groups being consulted.
15. For a Category A project, the project sponsor provides for the initial
consultation a summary of the proposed project’s objectives, description,
and potential impacts; for consultation after the draft EA report is prepared,
the project sponsor provides a summary of the EA’s conclusions. In
addition, for a Category A project, the project sponsor makes the draft EA
report available at a public place accessible to project-affected groups and
local NGOs. For FI operations, the FI ensures that EA reports for Category
A subprojects are made available in a public place accessible to affected
groups and local NGOs.
16. The Category B report (Environmental Review Summary) for a project
is made available to project affected groups and local NGOs.
17. Once the project sponsor officially provides a Category A EA report to
IFC, IFC distributes the summary (in English) to the members of IFC’s
Board of Directors. As required under its policy on disclosure, IFC also
makes the Category A EA and Category B environmental information
available through the World Bank InfoShop.14 If the project sponsor objects
to IFC’s releasing this environmental information through the World Bank
InfoShop, IFC staff do not continue work on the project. In rare and
compelling circumstances and for Category B projects only, an exception to
the time deadline associated with this public disclosure requirement may be
granted in writing by the Vice President, Investment Operations.
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Implementation
18. During project implementation, the project sponsor reports on
compliance with (a) measures agreed with IFC on the basis of the findings
and results of the EA, including implementation of any EAP, as set out in
the project documents; (b) the status of mitigatory measures; and (c) the
findings of monitoring programs. IFC bases supervision of the project's
environmental aspects on the findings and recommendations of the EA,
including measures set out in the legal agreements, any EAP, and other
project documents.
________________________
1. The International Finance Corporation (IFC) is the World Bank Group entity with a mandate to
invest in private sector projects in developing member countries. It lends directly to and makes
equity investments in private companies without guarantees from governments, and attracts other
sources of funds for these projects. IFC also provides advisory services and technical assistance
to governments and businesses. This policy also covers projects funded under the Global
Environment Facility (GEF).“EA” refers to the entire process set out in OP 4.01
2. For definitions, see Annex A. The area of influence for any project is determined with the advice
of environmental specialists and set out in the EA terms of reference.
3. See OP 4.12, Involuntary Resettlement , and OP 4.10, Indigenous Peoples (forthcoming); OD
4.20, Indigenous Peoples; and OP 4.11, Safeguarding Cultural Property in IFC-Financed Projects
(forthcoming).
4. Global environmental issues include climate change, ozone-depleting substances, pollution of
international waters, and adverse impacts on biodiversity.
5. For screening, see para. 8.
6. EA is closely integrated with the project's economic, financial, institutional, social, and technical
analyses to ensure that (a) environmental considerations are given adequate weight in project
selection, siting, and design decisions; and (b) EA does not delay project processing. However, the
project sponsor ensures that when individuals or entities are engaged to carry out EA activities,
any conflict of interest is avoided. For example, when an independent EA is required, it is not
carried out by the consultants hired to prepare the engineering design.
7. The panel (which is different from the dam safety panel required under OP 4.37, Safety of
Dams) advises the project sponsor specifically on the following aspects: (a) the terms of reference
for the EA, (b) key issues and methods for preparing the EA, (c) recommendations and findings of
the EA, (d) implementation of the EA's recommendations, and (e) development of environmental
management capacity.
8. These terms are defined in Annex A. Annexes B and C discuss the content of EA reports and
EAPs.
9. A potential impact is considered “sensitive” if it may be irreversible (e.g., lead to loss of a major
natural habitat) or raise issues covered by OP 4.10, Indigenous Peoples (forthcoming) ; OP 4.04,
Natural Habitats; OP 4.11, Safeguarding Cultural Property in IFC-Financed Projects (forthcoming);
or OP 4.12, Involuntary Resettlement .
10. When the screening process determines, or national legislation requires, that any of the
environmental issues identified warrant special attention, the findings and results of the Category B
EA may be set out in a separate report. Depending on the type of project and the nature and
magnitude of the impacts, this report may include, for example, a limited environmental impact
assessment, an environmental mitigation or action plan, an environmental audit, or a hazard
assessment. For Category B projects that are not in environmentally sensitive areas and that
present well-defined and well-understood issues of narrow scope, IFC may accept alternative
approaches for meeting EA requirements: for example, environmentally sound design criteria,
siting criteria, or pollution standards for small-scale industrial plants or rural works; environmentally
sound siting criteria, construction standards, or inspection procedures for housing projects; or
environmentally sound operating procedures for road rehabilitation projects.
11. The requirements for FI operations are derived from the EA process, and are consistent with
the provisions of para 6 of this OP. The EA process takes into account the type of finance being
considered, the nature and scale of anticipated subprojects, and the environmental requirements of
the jurisdiction in which subprojects will be located.
12. The criteria for prior review of Category B subprojects, which are based on such factors as
type or size of the subproject and the EA capacity of the financial intermediary, are set out in the
legal agreements for the project.
13. For projects with major social components, consultations are also required by other IFC
policies—for example OP 4.10, Indigenous Peoples (forthcoming), and OP 4.12, Involuntary
Resettlement.
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14. For a further discussion of IFC’s disclosure procedures, see IFC’s Policy on Disclosure of Information. Specific requirements for disclosure of resettlement plans and indigenous peoples development plans are set out in OP 4.12, Involuntary Resettlement (forthcoming), and OP 4.10,
Indigenous Peoples (forthcoming).
Annex A
Definitions
1. Environmental audit: An instrument to determine the nature and extent of
all environmental areas of concern at an existing facility. The audit identifies
and justifies appropriate measures to mitigate the areas of concern,
estimates the cost of the measures, and recommends a schedule for
implementing them. For certain projects, the EA report may consist of an
environmental audit alone; in other cases, the audit is part of the EA
documentation.
2. Environmental impact assessment (EIA): An instrument to identify and
assess the potential environmental impacts of a proposed project, evaluate
alternatives, and design appropriate mitigation, management, and
monitoring measures.
3. Environmental action plan: (EAP) An instrument that details (a) the
measures to be taken during the implementation and operation of a project
to eliminate or offset adverse environmental impacts, or to reduce them to
acceptable levels; and (b) the actions needed to implement these
measures. The EAP is an integral part of Category A EAs (irrespective of
other instruments used). EAs for Category B projects may also result in an
EAP.
4. Hazard assessment: An instrument for identifying, analyzing, and
controlling hazards associated with the presence of dangerous materials
and conditions at an installation. IFC requires a hazard assessment for
projects involving certain inflammable, explosive, reactive, and toxic
materials when they are present at a site in quantities above a specified
threshold level. For certain projects, the EA report may consist of the
hazard assessment alone; in other cases, the hazard assessment is part of
the EA documentation.
5. Project area of influence : The area likely to be affected by the project,
including all its ancillary aspects, such as power transmission corridors,
pipelines, canals, tunnels, relocation and access roads, borrow and
disposal areas, and construction camps, as well as unplanned
developments induced by the project (e.g., spontaneous settlement,
logging, or shifting agriculture along access roads). The area of influence
may include, for example, (i) the watershed within which the project is
located; (ii) any affected estuary and coastal zone; (iii) off-site areas
required for resettlement or compensatory tracts; (iv) the airshed (e.g.,
where airborne pollution such as smoke or dust may enter or leave the area
of influence); (v) migratory routes of humans, wildlife, or fish, particularly
where they relate to public health, economic activities, or environmental
conservation; and (vi) areas used for livelihood activities (hunting, fishing,
grazing, gathering, agriculture, etc.) or religious or ceremonial purposes of
a customary nature.
6. Risk assessment: An instrument for estimating the probability of harm
occurring from the presence of dangerous conditions or materials at an
installation. Risk represents the likelihood and significance of a potential
hazard being realized; therefore, a hazard assessment often precedes a
risk assessment, or the two are conducted as one exercise. Risk
assessment is a flexible method of analysis; a systematic approach to
organizing and analyzing information about potentially hazardous activities
or about substances that might pose risks under specified conditions. IFC
routinely requires risk assessment for projects involving handling, storage,
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or disposal of hazardous materials and waste; the construction of dams; or major construction works in locations vulnerable to seismic activity or other potentially damaging natural events. For certain projects, the EA report may
consist of the risk assessment alone; in other cases, the risk assessment is
part of the EA documentation.
Annex B
Content of an Environmental
Assessment Report for a Category A Project
1. An environmental assessment (EA) report for a Category A project1
focuses on the significant environmental issues of a project. The report's
scope and level of detail should be commensurate with the project's
potential impacts. The report submitted to IFC is prepared in English,
French, or Spanish, and the executive summary in English.
2. The EA report should include the following items (not necessarily in the
order shown):
(a) Executive summary. Concisely discusses significant findings and
recommended actions.
(b) Policy, legal, and administrative framework. Discusses the policy, legal,
and administrative framework within which the EA is carried out. Explains
the environmental requirements of any cofinanciers. Identifies relevant
international environmental agreements to which the country is a party.
(c) Project description . Concisely describes the proposed project and its
geographic, ecological, social, and temporal context, including any off-site
investments that may be required (e.g., dedicated pipelines, access roads,
power plants, water supply, housing, and raw material and product storage
facilities). Indicates the need for any resettlement plan or indigenous
peoples development plan2 (see also subpara (h)(v) below). Normally
includes a map showing the project site and the project's area of influence.
(d) Baseline data . Assesses the dimensions of the study area and
describes relevant physical, biological, and socioeconomic conditions,
including any changes anticipated before the project commences. Also
takes into account current and proposed development activities within the
project area but not directly connected to the project. Data should be
relevant to decisions about project location, design, operation, or mitigatory
measures. The section indicates the accuracy, reliability, and sources of the
data.
(e) Environmental impacts . Predicts and assesses the project's likely
positive and negative impacts, in quantitative terms to the extent possible.
Identifies mitigation measures and any residual negative impacts that
cannot be mitigated. Explores opportunities for environmental
enhancement. Identifies and estimates the extent and quality of available
data, key data gaps, and uncertainties associated with predictions, and
specifies topics that do not require further attention.
(f) Analysis of alternatives.3 Systematically compares feasible alternatives
to the proposed project site, technology, design, and operation—including,
the “without project” situation—in terms of their potential environmental
impacts; the feasibility of mitigating these impacts; their capital and
recurrent costs; their suitability under local conditions; and their institutional,
training, and monitoring requirements. For each of the alternatives,
quantifies the environmental impacts to the extent possible, and attaches
economic values where feasible. States the basis for selecting the
particular project design proposed and justifies recommended emission
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levels and approaches to pollution prevention and abatement. (g) Environmental action plan (EAP) . Covers mitigation measures,
monitoring, and institutional strengthening; see outline in OP 4.01, Annex C.
(h) Appendixes
(i) List of EA report preparers—individuals and organizations.
(ii) References—written materials, both published and unpublished,
used in study preparation.
(iii) Record of interagency and consultation meetings, including
consultations for obtaining the informed views of the affected people
and local nongovernmental organizations (NGOs). The record
specifies any means other than consultations (e.g., surveys) that
were used to obtain the views of affected groups and local NGOs.
(iv) Tables presenting the relevant data referred to or summarized in
the main text.
(v) List of associated reports (e.g., resettlement plan or indigenous
peoples development plan).
_______________________
1. The EA report for a Category A project is normally an environmental impact assessment, with
elements of other instruments included as appropriate. Any report for a Category A operation uses
the components described in this annex. IFC’s Environment and Social Development Department
can provide detailed guidance on the focus and components of the various EA instruments.
2. See OP 4.12, Involuntary Resettlement and OP 4.10, Indigenous Peoples (forthcoming).
3. EIA is normally best suited to the analysis of alternatives within a given project concept (e.g., a
geothermal power plant, or a project aimed at meeting local energy demand), including detailed
site, technology, design, and operational alternatives. Where a project has broad environmental
implications (e.g. a large reservoir), these should be addressed through a careful and
comprehensive analysis of the project’s area of influence and the proper scoping of the EIA.
Annex C
Environmental Action Plan
1. A project's environmental action plan (EAP) consists of the set of
mitigation, management, monitoring, and institutional measures to be taken
during implementation and operation to eliminate adverse environmental
and social impacts, offset them, or reduce them to acceptable levels. The
plan also includes the actions needed to implement these measures. 1
Action plans are essential elements of EA reports for Category A projects;
for many Category B projects, the EA may result in an action plan only. To
prepare an action plan, project sponsors and their EA design team (a)
identify the set of responses to potentially adverse impacts; (b) determine
requirements for ensuring that those responses are made effectively and in
a timely manner; and (c) describe the means for meeting those
requirements.2 More specifically, the EAP includes the following
components.
Mitigation
2. The EAP identifies feasible and cost-effective measures that may reduce
potentially significant adverse environmental impacts to acceptable levels.
The plan includes compensatory measures if mitigation measures are not
feasible, cost-effective, or sufficient. Specifically, the EAP
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(a) identifies and summarizes all anticipated significant adverse environmental impacts (including those involving indigenous people or
involuntary resettlement);
(b) describes—with technical details—each mitigation measure, including
the type of impact to which it relates and the conditions under which it is
required (e.g., continuously or in the event of contingencies), together with
designs, equipment descriptions, and operating procedures, as appropriate;
(c) estimates any potential environmental impacts of these measures; and
(d) provides linkage with any other mitigation plans (e.g., for involuntary
resettlement or indigenous peoples) required for the project.
Monitoring
3. Environmental monitoring during project implementation provides
information about key environmental aspects of the project, particularly the
environmental impacts of the project and the effectiveness of mitigation
measures. Such information enables the project sponsor and IFC to
evaluate the success of mitigation as part of project supervision, and allows
corrective action to be taken when needed. Therefore, the EAP identifies
monitoring objectives and specifies the type of monitoring, with linkages to
the impacts assessed in the EA report and the mitigation measures
described in the EAP. Specifically, the monitoring section of the EAP
provides
(a) a specific description, and technical details, of monitoring measures,
including the parameters to be measured, methods to be used, sampling
locations, frequency of measurements, detection limits (where appropriate),
and definition of thresholds that will signal the need for corrective actions;
and
(b) monitoring and reporting procedures to (i) ensure early detection of
conditions that necessitate particular mitigation measures, and (ii) furnish
information on the progress and results of mitigation.
Capacity Development and Training
4. To support timely and effective implementation of environmental project
components and mitigation measures, the EAP draws on the EA's
assessment of the existence, role, and capability of environmental units on
site.3 If necessary, the EAP recommends the establishment or expansion of
such units, and the training of staff, to allow implementation of EA
recommendations. Specifically, the EAP provides a specific description of
the project sponsor’s arrangements—who is responsible for carrying out the
mitigatory and monitoring measures (e.g., for operation, supervision,
monitoring of implementation, remedial action, financing, reporting, and
staff training). To strengthen the project sponsor’s environmental
management capability, most EAPs cover one or more of the following
additional topics: (a) technical assistance programs, (b) procurement of
equipment and supplies, and (c) organizational changes.
Implementation Schedule and Cost Estimates
5. For all three aspects (mitigation, monitoring, and capacity development),
the EAP provides (a) an implementation schedule for measures that must
be carried out as part of the project, showing phasing and coordination with
overall project implementation plans; and (b) the capital and recurrent cost
estimates and sources of funds for implementing the EAP.
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Integration of EAP with Project
6. The project sponsor’s decision to proceed with a project, and IFC’s
decision to support it, are predicated in part on the expectation that the EAP
will be executed effectively. Consequently, IFC expects the plan to be
specific in its description of the individual mitigation, management and
monitoring measures and its assignment of responsibilities, and it must be
integrated into the project's overall planning, design, budget, and
implementation. Such integration is achieved by establishing the EAP within
the project so that the plan will receive funding and supervision along with
the other components.
_________________________
1. The action plan is sometimes known as a “management plan.”
2. For projects involving rehabilitation, upgrading, expansion, or privatization of existing facilities,
remediation of existing environmental problems may be more important than mitigation and
monitoring of expected impacts. For such projects, the action plan focuses on cost-effective
measures to remediate and manage these problems.
3. For projects having significant environmental implications, it is particularly important that the
project sponsor have an in-house environmental unit with adequate budget and professional
staffing strong in expertise relevant to the project.
1. This policy allows IFC to waive certain environmental standards on
emission levels or approaches to pollution prevention and abatement (see
paragraph 6, OP 4.01). Even when waivers must be justified, this omnibus
clause seems to undercut Bank policies almost arbitrarily and should be
deleted. If waivers are required, IFC should seek specific Board approval.
Another viewpoint finds the new Handbook to be more flexible, reflecting
more holistic conceptual thinking, and expressing an ecosystem approach.
IFC’s demand-driven, single-project focus, however, means that to
operationalize this more comprehensive approach, IFC must work closely
with the Bank at project and sectoral levels.
OP 4.01, Environmental Assessment reflects, and is consistent with, the
Pollution Prevention and Abatement Handbook. The Handbook states
that: "New projects should meet the maximum emission levels contained in
the sector-specific guidelines unless the site-specific environmental
analysis (which the Bank Group requires for all projects that may affect the
environment and which takes into account local conditions and national
legislation) recommends stricter controls or provides a justification for a
variance from the guidelines contained in the Handbook." Depending on
host country laws and regulations and local conditions, for example, the EA
may result in recommendations for different requirements than specified in
the Handbook . In such cases the recommended variance must be fully
justified in the EA and any variance will only be acceptable if both IFC and
the project sponsor agree on the variance. IFC has established a
procedure that any variance from the Handbook requirements is approved
by IFC's Vice President, Investment Operations. IFC expects that a
variance allowing the use of lesser standards than those contained in the
Handbook will be permitted only in rare and compelling circumstances.
2. IFC projects should engender a sense of ownership in those populations
and communities they seek to benefit and the emphasis should be on
using local technology, resources, skills and standards wherever possible.
IFC agrees that locally affected people and communities should be
informed about proposed projects and be consulted about a project’s
positive and negative impacts and mitigation measures. This allows project
Consultation Comments
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pgpg pjaffected people and interested parties to submit informed feedback to project sponsors and financiers. IFC has written and published a Good Practice Manual (October 1998) as a “how to” guide for project sponsors in
implementing public consultation and disclosure activities. The Manual
includes a discussion on the use of local resources and training of the local
workforce to help foster community development in the project affected
area.
3. Where applicable, the EA report should include the resettlement plan
and the indigenous people’s development plan.
Resettlement plans and indigenous peoples action plans, where required,
are considered substantive EA addenda. For Category A projects, the
revised environmental and social review procedure (ESRP) requires that all
substantive addenda be disclosed and consulted on similarly to the
requirements for the Category A EA report.
4. The addition of an independent panel of experts for Category A projects
(OP 4.01, paragraph 4) is welcome, but the fact that it is the sponsor’s duty
to set it up could undermine its independence. IFC should make the
Panel’s recommendations mandatory, and not just advisory.
The Independent Panel of Experts is advisory to the project sponsor. The
Panel begins at the front end of the EA process and continues through
project implementation with the aim of bringing international best practice
to the project. While the Panel is retained by the project sponsor it retains
its independence from the project sponsor because members are experts
with international reputations to uphold. To ensure an interactive process,
IFC will review the recommendations of the Independent Panel both with
Panel members and the project sponsor.
5. IFC should include in OP 4.01 an assessment of cumulative and
associated impacts, as is common practice in the US.
Assessment of cumulative impacts normally is oriented to regional or
sectoral concerns, reflected in the World Bank version of OP 4.01,
Environmental Assessment. IFC has recognized that there may be some
projects that IFC is considering where it is appropriate to have the project
sponsor include consideration of cumulative impacts. IFC therefore has
included in the IFC environmental and social review procedure (ESRP)
language that reflects this: “The EA involves consideration of the following,
as appropriate to specific projects, cumulative impacts of existing projects,
the proposed project, and anticipated future projects” and “Project specific
EIA reports should normally cover … potential environmental and social
impacts (direct and indirect), including opportunities for enhancement; this
includes the cumulative impact of the proposed project and other
developments which are anticipated”. IFC has added a footnote to the
ESRP noting “The assessment of cumulative impacts would take into
account projects or potential developments that are realistically defined
and described at the time the EA is undertaken and where they would
directly impact on the project area.”
6. Paragraphs 3 and 12 of OP 4.01 speak of the need to assess national
environmental action plans and national legislation. The IFC environmental
assessment process should clearly identify national legal requirements,
and IFC projects should be judged in part by their compliance with
applicable national environmental laws and regulations.
In Paragraph 3 of OP 4.01, the EA process clearly states that “EA
considers natural and social aspects in an integrated way. It also takes
into account the variations in project and country conditions; the findings of
country environmental studies; national environmental action plans; the
country's overall policy framework and national legislation; the project
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countrys overall policy framework and national legislation; the project sponsor’s capabilities related to the environment, and obligations of the country, pertaining to project activities, under relevant international environmental treaties and agreements. IFC does not finance project
activities that would contravene such country obligations, as identified
during the EA.” The EA process, as laid out in IFC’s OP 4.01 therefore
requires a clear identification of national legal requirements related to the
environment. IFC’s environmental and social review procedure (ESRP)
requires the project sponsor to ensure compliance with host country
requirements. Investment agreements also contain covenants requiring
the project sponsor to comply with IFC and host country requirements.
7. In OP 4.01, paragraph 11, the discussion of financial intermediaries,
non-targeted funds requires clarification. It says, “IFC may…require that
investments…comply with host country requirements.” Under what
circumstances would compliance with host country requirements not be
mandated?
This implication resulted from a grammatical construct and was not the
intent. The language has been changed to “…IFC will require the FI to
receive training, if necessary. In addition, IFC requires that investments…
comply with host country environmental, health and safety requirements...”
58 Risø-R-1257(EN)
Appendix D Proposed Question-
naire on Existing Power System
Risø-R-1257(EN)59
WINSYS QUESTIONNAIRE1
1 See reference (J.C.Hansen & J.O.G.Tande, 1994)
Table 1 System identification data.
System
Status year
Annual load ex. desalination (MWh)
Annual desalination demand (m3)
Table 2 Conventional generating capacity.
G1 G2 G3
Site
Type specification
Installed cap.1 (kW)
Commissioned (year)
Lifetime (year)
Fuel type
Full load efficiency (%)
Min load efficiency (%)
Tech. min load (%)
Tech. availability (%)
Investment (ECU/kW)
Non fuel O&M (ECU/h)
Start/stop (ECU/#)
1 cos(ϕ) = 0.8
Table 3 Fuel specification.
Type
Heat value (kWh/kg)
Cost (ECU/kg)
Table 4 Misc. forecasts and plans.
Load forecasts
Conventional capacity expansion
Desalination demand forecasts
Fuel costs forecasts
Table 5 Wind data (air port, met.-mast, etc.)
Wind data time series (wind speed, direction)
Met. mast anemometer height (m)
Met. mast site description (map etc.)
Annual avg. temperature (deg. C)
Annual avg. air pressure (mBar)
Risø-R-1257(EN)60
Table 1 Desalination capacity (optional).
Desalination plant type
Capacity (m3/day)
Electric full load (kW)
Table 2 Load specification.
Jan-
Mar
Apr-
Jun
Jul-Sep Oct-
Dec
Hour
of day
Week-
day
(MW)
Week-
end
(MW)
Week-
day
(MW)
Week-
end
(MW)
Week-
day
(MW)
Week-
end
(MW)
Week-
day
(MW)
Week-
end
(MW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Risø-R-1257(EN)61
Table 8 Water demand specification (optional).
Hour of
day
Jan-
Mar
(m3)
Apr-
Jun
(m3)
Jul-
Sep
(m3)
Oct-
Dec
(m3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
62 Risø-R-1257(EN)
Bibliographic Data Sheet Risø-R 1257(EN)
Title and authors
Isolated Systems with Wind Power
An Implementation Guideline
Niels-Erik Clausen, Henrik Bindner, Sten Frandsen, Jens Carsten Hansen, Lars
Henrik Hansen and Per Lundsager
ISBN ISSN
87-550-2860-8; ISBN 87-550-2861-6 (internet) 0106-2840
Department or group Date
Wind Energy June 2001
Groups own reg. number(s) Project/contract No(s)
1120 084 – 00 EFP-1363/97-0007
Sponsorship
Danish Energy Agency (Energistyrelsen)
Pages Tables Illustrations References
614117
Abstract (max. 2000 characters)
The overall objective of this research project is to study the develop-
ment of methods and guidelines rather than "universal solutions" for the use of
wind energy in isolated communities. So far most studies of isolated systems
with wind power have been case-oriented and it has proven difficult to extend
results from one project to another, not least due to the strong individuality that
has characterised such systems in design and implementation.
In the present report a unified and generally applicable approach is at-
tempted in order to support a fair assessment of the technical and economical
feasibility of isolated power supply systems with wind energy.
General guidelines and checklists on which facts and data are needed to
carry out a project feasibility analysis are presented as well as guidelines how to
carry out the project feasibility study and the environmental analysis.
The report outlines the results of the project as a set of proposed guide-
lines to be applied when developing a project containing an application of wind
in an isolated power system. It is the author’s hope that this will facilitate the
development of projects and enhance electrification of small rural communities
in developing countries.
Descriptors INIS/EDB
DIESEL ENGINES; DISPERSED STORAGE AND GENERATION;
FEASIBILITY STUDIES; ON-SITE POWER GENERATION; POWER
SYSTEMS; RECOMMENDATIONS; REMOTE AREAS; RURAL AREAS;
WIND POWER
Available on request from Information Service Department, Risø National Laboratory,
(Afdelingen for Informationsservice, Forskningscenter Risø), P.O.Box 49, DK-4000 Roskilde, Denmark.
Telephone +45 4677 4004, Telefax +45 4677 4013, email: risoe@risoe.dk