Gustavo Hernández

 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 



 


 



Table of Contents

 

Acronyms  vii

List of illustrations  viii

List of tables  x

Preface  xiii

Executive Summary  xv

1       Introduction  1

2       Objectives  2

3       Micro-generation  2

4       Wind electricity generation – State of Art 3

5       Micro wind technology  5

5.1      Analysis of the wind available technologies  5

5.2      Micro-generation promotion  7

5.3      Efficiency  7

5.4      Detailed analysis and specifications  7

5.4.1    Noise  8

5.4.2    Visual impact 9

5.4.3    Avian considerations  12

5.4.4    Vibration  13

5.4.5    Ice and insects  14

5.4.6    Environmental considerations  16

5.4.7    Job Creation  17

5.4.8    Wind database  17

5.4.9    Power and Efficiency  19

5.4.10  Costs  21

5.4.11  On-roof downtown projects  22

5.4.12  Decommissioning  23

6       Regulations  23

6.1      Public safety considerations  23

6.2      Federal Regulations  25

6.3      Provincial Regulations  25

6.4      Municipal Regulations  26

7       Business cases  26

7.1      Scenarios  26

7.2      High level assessment 27

7.3      Solar Photovoltaic  27

7.4      Comparison of alternatives and evaluation  28

7.4.1    Assess Impact 28

7.4.2    Risks Assessment 29

7.4.3    Cost/Benefit Analysis  29

7.4.4    Comparison – Conclusions on alternative scenarios  30

8       On-roof Wind Project 31

8.1      Alternatives  31

8.2      Assess Impact 32

8.3      Risk Assessment 32

8.4      Business cases  33

8.4.1    Emission, Economy Stimulation, Saved Energy and Job Creation  34

8.5      On-roof project schedules  35

9       RECOMENDATIONS  35

Works consulted  39

Appendix A – Network development 45

Appendix B – Micro-generation growth in Alberta  46

Appendix C – Summary of areas to consider for wind generation turbines  47

Appendix D – History and Potential of micro-wind turbines in North America  49

Appendix E – HAWT Vs VAWT   50

Appendix F – EROEI for different technologies  52

Appendix G – Analysed wind turbines  53

Appendix H – Noise  54

Appendix I – NPP, SPP and Downtown Edmonton  55

Appendix J – Icing  61

Appendix K – Wind, buildings and turbulence  63

Appendix L – On-roof wind project around the world  65

Appendix M – Solar Photovoltaic (PV) analysis  67

M.1     Technology – stat of art 67

M.2     Cost analysis  67

M.3     Analysis of the technology in Alberta  68

M.3.1         Visual impact 69

M.3.2         Efficiency  70

M.3.3         Energy Balance  71

M.3.4         Job creation  72

M.3.5         Environmental cost 72

M.3.6         Micro-generation promotion  73

Appendix N – Risk analysis for the comparative alternatives  75

Appendix O – RETScreen Financial Analysis comparison Wind Vs. Solar Panel 76

Appendix P – Business case with different ROR and manpower considerations  77

Case 1  77

Case 2  77

Case 3  77

Appendix Q – Risk assessment for the four on-roof project alternatives  78

Appendix R – Business cases for the four on-roof alternatives  81

Appendix S – Schedules  84

 


 


 

Acronyms

 

 

AUC: Alberta Utilities Commission

DoE: DOE: Department of Energy

ERCB: Energy Resources Conservation Board

EROEI: Energy Return on Energy Investment

FAT: Factory Acceptance Test

GHG: Greenhouse Gases

GoA: GOA: Government of Alberta

GW: Giga Watt

GW/h: Giga Watt per hour

HAWTs: Horizontal Axis Wind Turbines

ktGHG: kilo tonne of GHG

kW: kilo Watt

kW/h: kilo Watt per hour

MG: Micro-generation

MGr: Micro-generator

MW: Mega Watt

MW/h: Mega Watt per hour

NPP: North Petroleum Plaza

OE: Office Ecology

OET: Office Ecology Team

PBL: Planetary Boundary Layer

PJ: Peta Joule

PJ/y: Peta Joule per year

PV: Photovoltaic or Solar Photovoltaic

SAT: Site Acceptance Test

SPP: South Petroleum Plaza

SWT: Small Wind Turbine

SWTS: Small Wind Turbine System

VAWTs: Vertical Axis Wind Turbines

W: Watt

 

 


 

List of illustrations

 

 

Figure 4.1 HAWT turbines

Figure 4.2 VAWT turbines

Figure 4.3 Special design turbines

Figure 5.1: Noise sources in the HWAT rotor plane

Figure 5.2: A specification of up to 55 decibels (dBA) allows not to be intrusive and to work under Edmonton city’s bylaw and international recommendations.

Figure 5.3: Time is service probability as function of the wind speed on NPP roof.

Figure 5.4: Total estimation installed height for the studied turbines

Figure 5.5: Wind Frequency Orientation distribution for NPP location 50 m of altitude.

Figure 5.6: Wind Frequency Speed distribution for NPP location at 50 m of altitude.

Figure 5.7: typical curves for different analysed turbines and the annual wind speed frequency distribution on NPP.

Figure 5.8: Total energy efficiency estimation for the analysed turbines considering the on-roof application in NPP. The average value, 20.5%, is shown as the red line.

Figure 5.9: Cost of wind project per kW of nominal capacity

Figure 6.1: view of Edmonton City Airport and NPP and SPP buildings

Figure 7.1: milestones in the development of the project

Figure 9.1: Total capital expenditure and project present value as function of the kW installed (two identical turbines).

Figure 9.2: Annual savings for wind electricity generation is represented in the yearly money paid by the GoA. The different curves represent different nominal wind turbine capacities.

Figure I.1: Downtown Edmonton

Figure I.2: NPP and SPP buildings south east view

Figure I.3: NPP and SPP buildings south view

Figure I.4: NPP and SPP buildings south west view

Figure I.5: NPP and SPP buildings west view

Figure I.6: NPP and SPP buildings north-west view

Figure I.7: NPP and SPP buildings north view

Figure I.8: NPP and SPP buildings north east view

Figure I.9: NPP ground view

Figure I.10: area viewshed for the turbines

Figure I.11: The hub height under the turbine is negligible this specification

Figure I.12: Minimum distance to perceive the turbine

Figure K.1: Wind-obstacle interaction for the turbulence formation and wind speed variation

Figure K.2: Neighbourliness consideration in the wind profile modification

Figure K.3: NPP and SPP show a relatively clean wind interaction with the neighbourhood buildings

Figure L.1: Examples of on-roof turbines around the world

Figure M.1: PV cost evolution

Figure M.2: Cost of the electricity by technology

Figure M.3: Visual impact of PV technology

Figure M.4: Solar radiation distribution around the world

Figure M.5: Canada and Alberta solar radiation distribution

Figure M.6: EPCOR headquarters PV installation

Figure M.7: PV project in the Alberta Legislature

Figure O.1: Financial Analysis - Solar Panel project

Figure O.2: Financial Analysis – Wind Project

Figure S.1: GoA alternative, it takes around 476 business days to be completed

Figure S.2: Eng alternative, it takes around 479 business days to be completed

Figure S.3: Com and Part alternatives, they take around 396 business days to be completed

 

 

 


 

List of tables

 

 

Table 4.1: Annual electricity and energy consumption in Alberta for 2006 in different sectors [45]

Table 4.2: Annual electricity and energy consumption in Alberta in 2008 [21]

Table 5.1: The following table presents the average wind farms efficiency in 2007 [2] [80]

Table 5.2: Avian mortality by technology

Table 5.3: GHG emission by technology

Table 5.4: Micro-generation shows great potential as job creator

Table 6.1: ISO 1996-1971 Recommendations for Community Noise Limits

Table 7.1: Sustainable ranking for different technologies

Table 7.2: Assess impact evaluation table

Table 7.3: Assess impact evaluation for the different four alternatives

Table 7.4: Risk assessment table

Table 7.5: Risk assessment outcome for the four different alternatives

Table 7.6: RETScreen summary for the ecominic comparison of the four alterantives

Table 7.7: RETScreen summary for the ecominic comparison of the four alterantives. Reasignation of funding

Table 8.1: Assess impact outcomes for the four alternatives developing the on-roof project

Table 8.2: Risk impact outcomes for the four alternatives developing the on-roof project

Table 8.3: Business cases summary for the four wind on-roof project development alternatives

Table 8.4: Summary of energy and emission to save by micro-generation technologies

Table 8.5: Summary of energy and emission to save associated to this on-roof project

Table 8.6: schedule for the development of the on-roof wind project for the four different alternatives

Table 9.1: GoA funding break down

Table 9.2: Minimal specification for the turbines

Table A.1: Stakeholders summary

Table B.1: Micro-generation development in Alberta up to June 2009 under the new regulation

Table E.1: Comparison between HAWT and VAWT technologies

Table F.1: EROEI index for different technologies

Table G.1: Summary of the studied turbines

Table H.1: Common Noise Production Levels

Table M.1: Wind and PV technology development in Alberta, Canada and the World

Table M.2: Summary of wind and PV technology development in Alberta, Canada and the World

Table M.3: Summary of job creation rations for wind and PV technologies

Table M.4: GHG emission for different technologies in Alberta according to RETScreen software

Table N.1: Risk analysis details for the four alternatives

Table P.1: On-roof wind project, business case 1

Table P.2: On-roof wind project, business case 2

Table P.3: On-roof wind project, business case 3

Table Q.1: Risk analysis details for the four in-roof wind alternatives

Table R.1: Wind project cost estimations

Table R.2: Energy and money saved over the time

Table R.3: Money recovered over the time

Table R.4: Summary of the business case for the DoE alternative

Table R.5: Summary of the business case for the Eng alternative

Table R.6: Summary of the business case for the Com alternative

Table R.7: Summary of the business case for the Part alternative

 

 


 


 

Preface

 

 

Many people have participated directly or indirectly in this project. We conducted consultation and discussions with stakeholders; this process was essential for the development of this study, knowing the available technology and sensing of the interest in the project. The technical specifications recommended are based on these discussions trying to meet several requirements for the special conditions of the project as well as to be the most practical and realistic possible according to the available technology today.

 

The images in the study, except those where is shown NPP and SPP, were obtained from Google images.

 

I'd like to thank people from OE Team that they collaborated polishing this study, the associated presentations and they provided ideas and information in the process of improvement (especially Carmen Gilmore, Chris Arnot, Henry Dakurah, Kathleen Pate, Kristin Stolarz and Maurine Mullins). Finally, I'd like to thank people from the GoA and CASA, who they allowed me to work and present this project (Andrei Nikiforuk, Matthew Machielse, Tim Grant and Kerra Chomlak).

 

This study represents the feasibility study for the development of the wind turbine micro-generation project on roof buildings. The three main objectives of the project is to provide a show case project supporting the micro-generation development in Alberta, to show the commitment of the Government of Alberta and the Department of Energy as well as leadership initiatives in environmental friendly source of energies. This study represents a guide and a point of start for the final project specifications. This document is the support of the presentation document (Power Point and Executive Summary) and it does not represent the final recommendations, which should be reached with more extensive discussions.

 

This study was carry on during the term of almost one year, but it is based on background experience and knowledge of the different actors that they participated. During this year, the technology, economic conditions and more have changed. The project, in any subject, was updated constantly during this year based on new evidence and boundary conditions. Many cares was taken to maintain the logic and congruent sequence of data, information and outcomes. In case of errors, omission, unclear or uncompleted data or information, the complete responsibility is assumed by the author of this study.

 

 

 

Gustavo Hernandez

January 2010

 

 

 

 

 


 

Executive Summary

 

 

Objectives

This study examines the promotion of micro-generation in Alberta through an inspiring example of wind generation. In addition, the Department of Energy (DOE) has the opportunity to demonstrate, once again, leadership and commitment to energy management, technology development, environmental protection and pro-active actions. Few opportunities are present over the time to demonstrate all this commitments.

 

Background

Micro-generation is the term used to describe generation of environmentally-friendly electricity on a small scale, i.e. for individual customer use. Alberta’s Micro-generation Regulation (announced in February 2008 and in force in January 2009) is the set of rules that allows electricity customers to generate their own environmentally friendly electricity and receive credit for any power they don’t use and send back to the electricity grid.

 

This regulation is based in the promotion of renewable and alternative sources of energy which present many benefits to society, market, environment, etc. These benefits include: efficiency and conservation, environmental considerations, business development, job creation, stabilizing electricity prices, decreasing requirements for transmission lines, etc.

 

Recommendations and Conclusions

We recommend that the DOE provide the funding and personnel to develop the wind micro-generation project in Edmonton downtown, preferably in North Petroleum Plaza (NPP) and with the cooperation of Alberta Environment in South Petroleum Plaza (SPP).

 

Alternative on-roof wind partner development offers the best value for the DOE, taking into account all factors: impact, risk, sustainability, investment, and investment recovery. Wind generation affords meaningful, sustainable development, promotion of micro-generation and positive impact on all stakeholders (including all Albertans). It will demonstrate the Government’s commitment to bolstering micro-generation business development in Alberta.

 

From a Government of Alberta (GOA) perspective, this project presents a positive presence in the Government core in downtown Edmonton, meets all the characteristics to promote the use of micro-generation in Alberta, and shows the commitment of the DOE and the GOA to efficient use of resources. In addition, the project presents a positive present value in its life doing that the on-roof wind project will pay for itself.

 

 

 

 

 

 

 

 

 


1          Introduction

This document represents the feasibility study of the on-roof wind generation facility based on NPP and SPP towers developed by the DOE’s Office Ecology Team (OET).

 

The DOE has the opportunity to model the efficient use of energy and available micro-generation resources. This initiative develops a multiple gain scenario where multiple players collect several benefits in a positive feedback:

-          Micro-generation promotion:

o   Improves the electricity generation matrix in Alberta;

o   Promotes the use of alternative and renewable sources of energy;

o   Promotes energy efficiency;

o   Helps reduce electricity costs;

o   Helps decrease electricity cost volatility; and

o   Decreases energy losses in transmission lines.

-          Social:

o   Helps educate citizens on Energy Efficiency and Energy Conservation;

o   Increases micro-generation businesses;

o   Increases employment;

o   Increases community commitment and awareness of energy efficiency and use; and

o   Increases Research and Development (R&D) initiatives in Alberta;

-          Economics:

o   Saves money in Micro-generation promotion and education;

o   Reduces electricity consumption in the proposed buildings; and

o   As micro-generation technology:

-          Helps reducing wholesale electricity price and volatility;

-          Increase the energy efficiency;

-          Helps in the development of micro-generation businesses; and

-          Help in job creation at all levels (research, management, maintenance, operation, administration, etc).

-          Environment:

o   Saves emission;

o   Promotes the use of renewable and alternative sources of energy; and

o   Contributes to provincial targets achievement in emissions reduction.

-          DOE and GOA:

o   Shows the commitment of DOE and GOA through an inspiring example; and

o   Shows DOE and GOA are taking the initiative in energy efficiency, renewable and alternative energy use, and energy cost reductions that face Albertans.

 

2          Objectives

The objective of this analysis and comparison is to maximize the following:

1.      Promote micro-generation

2.      Improve energy use and conservation

3.      Promotion energy efficiency

4.      Promote Greenhouse Gas (GHG) emissions reduction

5.      Promote micro-generation business development

6.      Effective investment of government monies

7.      Risks minimization

8.      DoE and GoA commitment

9.      DoE and GoA initiative

 

3          Micro-generation

Micro-generation is the term used to describe generation of environmentally-friendly electricity on a small scale—for individual customer use. In Alberta, micro-generation is one megawatt or less of electricity generation that is connected to the distribution system. Alberta’s Micro-generation Regulation is the set of rules that allows electricity customers to generate their own environmentally friendly electricity and receive credit for any power they don’t use and send back to the electricity grid. Appendix B presents details of micro-generation installation under this regulation.

 

Micro-generation use produces significant positive effects in energy use and in the electricity market:

·         Increases the efficiency in the residential sector as well as energy use in rural areas.

·         Increases renewable and alternatives source of energy. Micro-generation is the base of all the technologies allowed for micro-generation and all of them help in emission reduction.

·         Decreases energy consumption: the so-called “second effect” produces around a 6% decrease in electricity consumption due to awareness around electricity use.

·         Decreases losses in transmission lines: electricity is generated on site, eliminating the need for transmission lines (between the 6 and 8 % of the electricity generated in Power Plants is lost due transmission and distributions lines losses).

·         Stabilizes and decreases the cost of the electricity: on peak hour cost of electricity has a huge impact in daily electricity price; micro-generation helps reduce on peak demand, and has a secondary effect of increasing awareness in consumption along with reducing the on peak electricity cost.

·         Micro-generation business: increase the number of micro-companies offering for micro-generation technology, installation and maintenance.

·         Although there is worldwide consensus in favour for the wind generation development, many voices can be heard stressing the weaknesses of wind generation technology such as increased electricity price, the need for backup because of the unpredictability of the resource, etc. This awareness does not apply for micro-generation due to the scale of the technology.

4          Wind electricity generation – State of Art

Over the years, the worldwide contribution for the development of wind technology offers a widespread technical possibility to use this technology for electricity generation. Nowadays, there are wind turbines with a capacity of a few Watts (W) to Megawatts (MW), turbines for applications in extreme weather conditions, top-roof turbines, in a hill, on-shore and off-shore, etc.

 

In December 2008, Canada counted with two Gigawatts (GW) of installed wind capacity [2], increasing this number by 46% per year during the period of 2004-2008. Alberta is one of the leaders in Canadian wind development with a capacity of 540 MW of installed power capacity. In addition, Alberta had one of the better wind capacity coefficients in Canada: 35% wind in 2007 and 32.4% in 2008 [2]. Finally, the Alberta Electric System Operator (AESO) had 81 wind projects in its queue in Alberta, representing nearly 11,714 MW [21].

 

If Alberta installed wind turbine in all appropriate sittings, Alberta’s maximum estimated wind capacity, at the current technical development, is 400,000 MW with an electricity production of 2,100,000 GWh/y or 7,500 PJ/y. If we compare these numbers with the annual electricity and energy consumption by sector in Alberta, the importance in the development of this technology provincially and country wide is evident.

 

Sector

Annual electricity consumption [GWh]

Annual energy consumption [PJ]

Residential

6,810

179

Transportation

110

405

Industrial

27,900

832

Commercial

13,500

154

Table 4.1: Annual electricity and energy consumption in Alberta for 2006 in different sectors [45]

 

Item

 

2008 Electricity Consumption [GWh]

70,000

2008 Generation Capacity [MW]

12,300

Table 4.2: Annual electricity and energy consumption in Alberta in 2008 [21]

 

Different publications [12], [17], [20],[26] and [28] analyse wind resources assessment models, site selection models and aerodynamic models including wake effect, leading discussions about existing performance and reliability evaluation models, various problems related to wind turbine components (blade, gearbox, generator and transformer) and the grid system development for integrating the wind energy system. In particular [17] has an extensive database of referred studies for each concern associated to wind technology.

 

Basically, two different types of wind turbines exist, the horizontal and vertical axis wind turbines (HAWTs and VAWTs); the horizontal axis wind turbine is the most common type. Several sub-classifications exist for them. Figures 4.1, 4.2 and 4.3 show the most common turbine classification.

 

Castle Tower in London, should be completed in 2009.

a)    Classic

b)   On-roof design

c)     Multiple blades

d)    Integrated

Figure 4.1:  HAWT turbines

 

  Darrieus Vertical-Axis Wind Turbine 

e)    Helical

f)    L-shaped

g)    Darrieus

h)    H-rotor

Figure 4.2: VAWT turbines

 

マグナス効果 AIR%20ROTOR%20SYSTEM%20in%20Flight%5B12%5D - Beautiful wind turbines - wind generatorshttp://www.aerotecture.com/projects_mlh/1.jpg

i)     Magnus effect

j)     Floating

k)    Integrated

l)      Helical on-roof

Figure 4.3: Special design turbines

 

 

The first windmill was a VAWT; later HAWTs received most attention, but some scientists [32] claim that the HAWT is not obviously better than the VAWT just because it was randomly picked long ago for large-scale development.

 

Appendix C presents more details in the analysis of wind turbines.

 

5          Micro wind technology

Evidence indicates that people view small and large wind turbines the same even though they have very different characteristics [82][83]. The technology principles are the same, but both industries are different, with different boundary conditions, cost, market and goals.

 

Small Wind Turbines (SWT) are classified as:

·         Mini wind turbines with a rated power output from 300 W up to 1000 W (1 kW);

Capitalizing on the potential market in Alberta (not possible in practical point of view nowadays) would result in the installation of over 100 MW of Small Wind Turbines System and GHG emission reductions of over 250 ktGHG per year [2]. Each MW of installed wind power in Alberta today, represents an emission reduction of 2.5 ktGHG per year.

At the present, the market for SWTs in Canada is relatively small, although it has experienced some growth in the past five years [2]. A survey of retailers, distributors and manufacturers of SWTs revealed the following:

·         Annual Sales. It is estimated that current annual sales of SWTs are in the range of 600 to 800 units per year. This represents roughly $3.5 million in annual sales, including $2.3 million for mini wind turbines and $1.2 million for small wind turbines.

Appendix D shows the evolution over the time of micro-wind in North America.

 

5.1       Analysis of the wind available technologies

There is some concern in the use of HAWT technology for on-roof wind project. These concerns focus on the effect of the turbulence on the turbine performance, durability, control performance, maintenance cost, vibration, etc [36]. New on-roof design for HAWT removes those weaknesses (figure 3.1-b), although some projects were developed with success, the commercialization period of this technology did not occur. VAWT technology overcomes most of those weaknesses, but it adds others.

 

An omni-directional turbine can be situated at places where the wind is turbulent and where the wind direction changes often. For this reason, VAWTs have an advantage over HAWTs in high mountain areas, in regions with extremely strong or gusty winds and in urban areas [35][37]. Investigations indicate a clear advantage in using VAWTs at rooftops [36]. Furthermore, the VAWT is less noisy than the HAWT, which becomes even more important in urban areas [35] as well as less dangerous for birds [17].

 

VAWTs appear to be advantageous to the horizontal axis wind turbine in several aspects for roof applications. Reports advise of the inconvenience to install a HAWT on a building roof [36] due to high turbulence, less life of the turbines and less energy production. However, the use of VAWT in cities has increased due to the natural advantages of VAWT technology for this market sector. Around the world, multiples studies have been conducted (Ontario [39], Brampton, Canso, Kingston, Marathon, Wawa, Wolf [44], Germany [40]) and roof mounted VAWTs have been proposed as part of the energy source for the Freedom Tower in New York City [38].

 

The vertical rotational axis of a VAWT allows the generator to be located at the bottom of the tower. This makes installation, operation and maintenance much easier. The tower can be lighter for a VAWT since the nacelle is excluded, which reduces structural loads and problems with erecting the tower [41]. The generator design can be focused on efficiency, cost and minimising maintenance. Furthermore, the control system can also be located at ground level facilitating access.

 

The blades of a HAWT have to be self-supporting since they are only attached at the root. The blades of a VAWT are supported by support arms, which usually are attached to the centre of the blades. However, the support arms add extra structure and mass to the turbine. For a larger blade area, more material is used. Mass production of VAWT blades would imply low production costs since their shape makes them easy to fabricate in large numbers compared to HAWTs [41].

 

More discussions about the HAWT and VAWT differences are exposed in Appendix E where a summary is presented comparing HAWT and VAWT technologies.

 

5.2       Micro-generation promotion

Wind technology presents important characteristics in the promotion of micro-generation technologies and renewable sources of energy.

 

The effect in the community is extremely large at the start of the project, and it persists over time with the same intensity for several generations. The movement, and its variation, produces a double effect as it captures people’s attention to this technology.

 

To settle the wind turbine in the downtown of a populous city stress significantly the promotion of the technology and micro-generation as a general concept.

 

5.3       Efficiency

In 1919 the physicist Albert Betz showed that for a hypothetical ideal wind-energy extraction machine, the fundamental laws of conservation of mass and energy allowed no more than 16/27 (59.3%) of the kinetic energy of the wind to be captured [28][46]. This Betz' law limit can be approached by modern turbine designs which may reach 70 to 80% of this theoretical limit.

 

Today, the available wind energy conversion efficiency reaches about an average of around 40% in modern wind turbine types. The common value for most of installation is between 30 and 35% in wind farm and between 20 and 32 % for on-roof applications. Considering the losses due to energy operation of the turbine components, this efficiency decreases in around 4 % more [35] [36] [37]. The following table presents the average wind farms efficiency in Alberta, Canada and the World for 2007.

 

 

 

Alberta

Canada

World

Wind efficiency for electricity generation [%]

32.9

32.8

34

Table 5.1: The following table presents the average wind farms efficiency in 2007 [2] [80].

 

Another important concept related to the efficiency of the different technologies is the called The Energy Return on Energy Investment (EROEI) index; this index shows the relationship between these two amounts of energy. Appendix F presents the EROEI for different technologies for comparison; wind technology has an EROEI between 10 and 18.

 

5.4       Detailed analysis and specifications

Thirty-five different turbines/technologies were taken as reference to compare and work in the selection of specifications; the companies which provide these turbines provided significant expertise, comments and discussion for the project estimation (cost, time, risk, etc.) and stakeholder network development. The summary of these turbines is presented in Appendix G.

 

5.4.1    Noise

Noise from wind turbines (when active) may interfere with the lives of animals beneath the wind turbines. Wind turbine noise is one of the major hindrances for the widespread use of wind energy [8][77][78]. In order to reduce wind turbine noise the source mechanisms must be known. For a modern large wind turbine, aerodynamic noise from the blades is generally considered to be the dominant noise source, provided that mechanical noise is adequately treated [11].

 

Due to the large number of applications (e.g. wind turbines, airplanes, helicopters, fans), the characteristics of airfoil noise have been investigated extensively in both experimental and theoretical studies. Both inflow-turbulence and self-noise mechanisms were considered and the dependence on parameters such as flow speed, angle-of-attack, radiation direction, and airfoil shape was characterized. These studies formed the basis of several semi-empirical wind turbine noise prediction models, which were validated by comparison to field measurements. Since the field results only provided the overall sound level of the turbine, the relative importance of the different mechanisms was determined mainly on the basis of the predictions. In some studies inflow-turbulence noise was regarded to be the dominant source, while others considered trailing edge noise to be dominant. In another case the turbine noise in different frequency ranges was attributed to mechanical noise, trailing edge noise, tip noise, and inflow-turbulence noise.

 

Figure 5.1: Noise sources in the HWAT rotor plane.

 

In [37] is reported a serious concern related with on-roof turbine and the noise annoyance that they present. Appendix H presents the common noise production levels.

 

The VAWT technology, specifically the H-rotor turbine, is expected to produce much less noise than a HAWT technology. There are two main sources for wind turbine noise; aerodynamic noise from the turbine’s blade tips and mechanical noise from the drive train components. The aerodynamic noise increases with increasing blade tip speed of the turbine. A VAWT usually has a tip speed which is approximately half the tip speed of a HAWT and it therefore produces less aerodynamic noise. Since a VAWT has the drive train components at ground level, the possible noise from these parts will not propagate as easily as when the drive train components are situated on top of the tower. The VAWTs rotate slower than a HAWT of the same size; it will therefore produce less noise than the HAWT [17][41]. The following figures show the noise levels for two different turbines; in the left side a VAWT turbine noise level is represented (OE-8) and in the right side a HAWT turbine noise level is presented (OE-1). 

 

 

 

Figure 5.2: A specification of up to 55 decibels (dBA) allows not to be intrusive and to work under Edmonton city’s bylaw and international recommendations.

 

5.4.2    Visual impact

This is a subjective concept; the visual impact of wind farm is considered positive (Prince-Edward Island [2]) in some regions but negative in others (Gaspésie, Quebec [2]).

 

In the present project, the potential visual impact is inverted; the showcase characteristics of this project convert the visual impact into a key role in the project definition. The turbine design must harmonize in shape, colour, wide, tall, etc. with the building and lateral buildings looking for the most efficient and harmonious visual impact in the promotion of MG. The swept area (area covered by the turbine in its rotation) of the turbine should be enough to capture the attention of people.

 

Different studies show a detailed assessment in visual impact caused by wind farms and off-shore projects [6] [7] [8] [58]; for on-roof turbine the concerns focus on disrupting scenic of old, historical, community buildings, etc. In the downtowns of modern cities, the concern is diluted by the characteristics of the cities themselves (essentially moderns and tall buildings).

 

The first step in maximizing the on-roof wind positive visual impact is to map the locations from which the turbines would be visible. These locations, defined as the set of points from which an observer could see any of the turbines on a clear day, are collectively known as the viewshed. Due to the NPP and SPP height in comparison to neighbouring buildings, the turbines on-roof NPP and SPP do not offer viewshed intersections with other buildings. Taller buildings in downtown Edmonton do not need consideration because they are located as far as one kilometre away. Taller buildings in downtown area are not allowed because of Edmonton’s city airport. Appendix I presents figures that show the buildings location in real proportion size in downtown Edmonton, as well as an analysis of visual specifications.

 

A negative effect of wind turbine visual impact showcase is the time during the turbine is not turning; a wind turbine doesn’t turn all time. If the wind speed is slow, it doesn’t have enough energy to move the turbine. This state represents a negative effect as showcase. This minimum energy depends of multiples factors such as kind of turbine, turbine power, installation, etc; the project design must maximize the time that the turbine is spinning. The following figure shows the time in service probability as function of the wind speed in on NPP roof for the four seasons and the annual average. The figure shows that for example for a cut-in of 3 m/s the turbine will be working around of 70% of the time during the summer (17.8 hours per day) and 85% during the winter (20.4 hours per day).

 

Figure 5.3: Time is service probability as function of the wind speed on NPP roof.

 

 

As summary for visual impact specifications:

-          A swept area between 6.3 and 125 m2;

-          10 meters maximum height;

-          1.4 meters minimum turbine height (without hub);

-          The turbine colour must following Canadian Aviation Regulations; when it is possible, it should  be some colour which maximizes the contrast with the white, grey and light blue colour of the sky;

-          The turbine colour must following Canadian Aviation Regulations; when it is possible, the turbine must have illumination during the night fed by the same system (the light should be on when the turbine is spinning);

-          It should be study the psychological effect for the population in the change of colour light if the turbine is spinning or not; and

-          Cut- in 3 m/s, maximizing the time turning of the turbine.

 

The following figure shows the total estimation installed height for the studied turbines:

 

 

Figure 5.4: Total estimation installed height for the studied turbines

 

5.4.3    Avian considerations

The results of many studies [14][10][71] [72] [73] [74] suggest that:

·         Wind farms kill millions of birds yearly around the world, and the high mortality of rare raptors is of particular concern; a greater kill of large birds, raptors and predators is detected in wind farms; raptors glide most of the time to save energy and they use ascending air currents which often form along slopes and ridges, where wind plants are often located for the same reason;

·         Wind farms on migration routes are particularly dangerous, and it is difficult to find a wind power site away from migration routes because there is no guarantee that migration routes will not vary;

·         According to the model of collision probability, the rotor speed does not make a significant difference in collision probability; the hub is the most dangerous part, and large birds (e.g. raptors) are at great risk;

·         based on the field observation of squirrels’ vocalisation (i.e. anti-predator behaviour), there are behavioural differences between squirrels at the wind turbine site and those at the control site; and

·         Several wind farms are erected in the way of migratory routes.

 

In [72], the researcher goes further and reaches a relationship between bird fatalities and power generation for different technologies. The author establishes the existence of the bird and bat fatalities associated to wind farms, but he argues that this relative concept changes when we compare the birds killed per kilowatt-hour for different electricity generation facilities. For fossil fuel power plants the author considers the bird killed in coal mining, plant operation, acid rain and mercury. For Nuclear power plants, the author considers the uranium mining and milling, and plant operation; the result is presented in the following table.

 

 

Facility

Avian mortality per GWh

Fossil fuel Power Plant

0.200

Nuclear Power Plant

0.416

Wind Farm

0.269

Table 5.2: Avian mortality by technology

 

The conclusion in aims to show that, instead of the problems exist in wind farms, the effect is over dimensioned. For wind farms the effect is magnified because the avian mortality occurs in a very small area. Another interesting effect, based on the register following this problem, shows that the avian fatalities are sensitive to time: birds often learn to avoid wind farms after their first few years of operation.

 

A special concern is the slaughter of bats; the University of Calgary has conducted studies due to the high rate of bats killed by certain turbines of southern Alberta. The study determined that the vast majority of bats found dead below turbines suffered severe injuries to their respiratory systems consistent with a sudden drop in air pressure that occurs when the animals get close to turbine blades. Several universities in Canada are studying procedures and mechanism to diminish this slaughter of bats [85].

 

There are not conducted important studies on slaughter of birds in on-roof wind turbine installations; due to low power capacity, low swept area in on-roof project development and absence of the main concern factors, the slaughter of birds doesn’t represent an issue for on-roof wind turbines. 

 

In relationship with the turbine technology, the VAWT is expected to be less harmful for birds and bats, since the blades move at a slower pace and the speed of the blade has been shown to affect the risk for collision greatly [17][53].

 

Based on these studies, we can conclude that the expected avian mortality for the on-roof project is almost null. If some mortality occurs is more related with fatality than a strict correlation of the factors.

 

5.4.4    Vibration

In [60][61][62] is presented both experimental and theoretical methods to study the structural dynamic characteristics of rotor blades to avoid sympathetic vibration problem. The test revealed that the natural frequencies of flap wise vibrations are lower than that of the torsional vibrations; flap-wise vibration is the main vibration of the rotor blade.

 

Cyclic stresses fatigue the blade, axle and bearing; material failures were a major cause of turbine failure for many years. Because wind velocity often increases at higher altitudes, the backward force and torque on a HAWT blade peaks as it turns through the highest point in its circle. The tower hinders the airflow at the lowest point in the circle, which produces a local dip in force and torque. These effects produce a cyclic twist on the main bearings of a HAWT. The combined twist is worst in machines with an even number of blades, where one is straight up when another is straight down. To improve reliability, teetering hubs have been used which allow the main shaft to rock through a few degrees, so that the main bearings do not have to resist the torque peaks.

 

When a HAWT turbine turns to face the wind, the rotating blades act like a gyroscope [63][64]. As it pivots, gyroscopic precession tries to twist the turbine into a forward or backward somersault. For each blade on a wind generator's turbine, precessive force is at a minimum when the blade is horizontal and at a maximum when the blade is vertical. This cyclic twisting can quickly fatigue and crack the blade roots, hub and axle of the turbines.

 

VAWT vibration is originated by different physics principles due to the nature of the turbine. More blades diminish vibration problems, but also decrease the turbine efficiency.

 

All engines turning have an inherent vibration problem, and all consequences associated to this phenomenon. Special materials, sensors and theories to mitigate the problem have been developed for hundreds of years. All this technology and procedures are available today for simple turbines applications. However, heavy turbine associated to vibration problems could produce important and quick damage in the turbine basement.

 

For on-roof turbines, especial considerations should be taken to avoid vibration transmission through the building; these considerations should aim structural implications, turbine life, people welfare and efficiency; real-time monitoring, periodic maintenance and inspections are mandatory. The vibration transmission/isolation technology is extremely well known, many industries face similar problems and hundreds of instruments, software, theories and solution are available. Vibration transmission to the building represents a problem in itself, but the solution is available at all levels.

 

5.4.5    Ice and insects

Often the locations for wind turbines are in exposed locations where they are subject to icing of the blades. Icing of wind turbine blades can cause a variety of problems, such as complete loss of production, reduction of power due to disrupted aerodynamics, overloading due to delayed stall, increased fatigue of components due to imbalance in the ice load, and damage or harm caused by uncontrolled shedding of large ice chunks [75][76].

 

The insect factor has a similar effect for the wind turbine performance that icing, but it does not involve public risk. Humid regions are more affected by this phenomenon and it presents its own particularities. Insects prefer to fly in conditions of high air humidity, low wind and temperatures above about 10° Celsius. Under these circumstances, they will increasingly foul the leading edges of the blades.

 

Stall control is not very accurate in practical application, and many stall-controlled turbines do not meet their specifications. The power of wind turbines operating in high winds has been known to drop for no known reason, causing production losses from 25 to 50%—a phenomenon referred to as a ‘Double Stall’ or a ‘Multiple Stall’. Some researchers [76] attributed this multiple power level occurrence to the insect theory, which states that these levels correspond to different degrees of insect contamination. A low contamination level decreases the power by 8% of the design value; while at high levels it can be decreased by up to 55%. In this study a device called a ‘stall flag’ was employed a hinged flap that opens up in a separated airflow to uncover an individual reflector.

Employing a projector as a light source, they measured the separated flow from the intensity of reflected light.

 

The most common solution for reducing the effect of insects and air pollutants on the blades is to wait for rainfall to wash the blades. The disadvantage of this system is that the wind turbine must be stopped, so the resulting power loss will simply add to the losses created by the insects. Another blade washing technique involves pumping water up through the tower and spraying it into the wind and through the blade tip, a solution that can be implemented while the turbine is in operation.

 

Icing and insect problems involve a maintenance requirement for the turbines. Because the Edmonton region is could experience both problems, measures should be specify for an on-roof turbine:

-          Periodic maintenance during the periods with the temperature and humidity are medium/high;

-          Periodic maintenance, passive (e.g. dark colour for blades to absorb energy) and active methods de-icing and/or anti-icing.

 

Furthermore, problems with icing are less severe with a VAWT compared to a HAWT and less security distance is required. This is due to the lower rotational speed of a VAWT but also since an ice part that comes loose cannot get a velocity directed upwards when leaving a VAWT, as could be the case with ice parts leaving a HAWT blade.

 

 

5.4.6    Environmental considerations

Wind power consumes no fuel for continuing operation, and has no emissions directly related to electricity production. Operation does not produce carbon dioxide, sulphur dioxide, mercury, particulates, or any other type of air pollution, as fossil fuel power sources do. Wind power turbines consume resources in manufacturing and construction. As summary, the following table presents the estimation in average GHG emission for different technologies [81].

 

Technology

g/kWh

Coal

850 – 1100

Coal with CCS

85 – 220

NG Simple Cycle

550 – 680

NG Combined Cycle

400 – 520

Geothermal for Electricity

40 – 115

Biomass

-40 – 40

Wind

20 – 55

Photovoltaic

40 – 120

Solar Thermal

30 – 100

Nuclear

20 – 35

Hydro-electric

10 – 30

Table 5.3: GHG emission by technology

 

The GHG emission intensity for the electricity industry in Alberta was 930 g/kWh in 2006 [84]. This means that 10 kW of installed wind power in Alberta represents an emission reduction of 25.3 tGHG per year, this is comparable to:

·         5 cars off of the road, or

·         300 fluorescent tubes less, or

·         5,100 toner cartridges not used, or

·         4,500 people take the bus between St. Albert and Edmonton, or

·         1,800,000 paper cups of coffee not used, or

·         2,500,000 A4 sheets not used.

 

During manufacture of the wind turbine, steel, concrete, aluminum and other materials will have to be made and transported using energy-intensive processes, generally using fossil energy sources. The initial energy "pay back" is claimed by one company to be within about 9 months of operation for their offshore turbines and the British Wind Energy Association claim the average wind farm will pay back the energy used in its manufacture within 3 to 5 months of operation. However, a report to the British House of Lords in 2004 suggested a payback time of 1.1 years, taking into account factors such as plant construction and decommissioning. A shorter period for offshore facilities was given, as the higher capacity factors would more than offset the added energy costs of installation.

 

On-roof turbines do not have environmental concerns for site installation, another impact which that wind farms must consider.

 

5.4.7    Job Creation

The following table presents the estimation in rate of job creation for some technologies [56] for big scale applications; for micro-generation applications, the factor of increase is between 10 and 15.

 

 

Renewable energy

Construction & installation Ratio per [MWp]

Operation & maintenance ratio per [MWp]

Wind

1.5

0.3

Coal fired Power Plant

0.27

0.74

Biomass

0.4

1.4

NG fired Power Plant

0.25

0.7

Table 5.4: Micro-generation shows great potential as job creator

 

 

5.4.8    Wind database

The stochastic nature of wind is an important constraint for wind projects and turbine design. The majority of today’s wind turbines operate within the first 100 m of the earth’s surface. This region, which occupies the lowest portion of the planetary boundary layer (PBL), is extremely turbulent and driven by variations, which occur with the diurnal http://www.bergey.com/Maps/World.Wind.Lg.jpgchanges in the atmospheric boundary conditions. The vertical variation of temperature and wind speed with height defines the PBL behaviour characteristics. During normal daytime turbine operations, the temperature normally decreases with height, which contributes to a convectively unstable atmosphere. Under these conditions, the largest and most energetic turbulent motions are associated with convective edges or cells that are many times larger than even the largest wind turbines. The large eddies actively mix with and absorb the smaller, more compact turbulent structures that have a more direct impact on rotating wind turbine blades. These effects are increased in cities were human activity means more temperature variations. Appendix K presents more details.

 

Canadian Wind Energy Atlas [1] provides a database for the average wind frequency and direction for Edmonton region. The available data is for three different altitudes: 30, 50 and 80 meters. This database does not take into consideration several application factors such as wind interaction in urban areas, nozzle effect due to buildings, turbulence, interaction between obstacles and obstructions, etc. According to different publications [2][3][4], all those factors increase the wind turbulence but decrease the average wind speed in building such as NPP and SPP. Based on this conclusions the database for 50 m is taken.

 

Wind direction will have also variations in relationship with the working database. This variation will not be significantly affected due to the rotation capacity of each wind generation unit, but it has an effect on the work and energy required in the control orientation of the turbine.

 

Figure 5.5: Wind Frequency Orientation distribution for NPP location 50 m of altitude.

 

 

Figure 5.6: Wind Frequency Speed distribution for NPP location at 50 m of altitude.

 

 

Although the useful database provided by [1], the urbane zone interaction generates distortions of this frequency distribution and before to start the project measures during a period of time the real conditions on top of the building is necessary. The efficiency of the wind turbine is obtained through the composition between this wind frequency speed distribution and the power curve of each turbine. To know the real wind conditions on the roof of the building will allow selecting better turbine and its better operating conditions.

 

5.4.9    Power and Efficiency

One of the significant measures of the cost effectiveness of a wind turbine is its production of energy. In the design and analysis of wind turbines, the annual energy output is calculated. Calculation of annual energy output requires knowledge of the wind speed frequency distribution and the system power output of the turbine as a function of wind speed. Furthermore, every prediction of annual energy output is specific, depending on the local wind flow patterns and turbulence and the local air density [19][21].

 

Turbine height was found to have a significant effect on mean wind speed and power generated, while output varied considerably with wind direction. The optimum mounting position was also found to be dependent on the wind direction. If the probability of wind flowing from all directions is similar, however, turbine location was found to be unimportant provided that the turbine was located above roof height. With a strong prevailing wind direction, optimum mounting position is likely to vary.

 

Several factors affect the power output and efficiency in electricity generation for a turbine; the most important factor is the correct selection of the turbine for the wind conditions in the site. The wind condition is a statistic result of the study during a period of time in the exact location where the turbine will be located. For on-roof projects, this study presents a big concern that must be specially considered. Many factors affect the wind frequency distribution and intensity in cities and they change over the time.

 

Urban wind monitoring projects in Europe, the UK and the USA consider the future viability of roof-top turbines in urban houses, the advantages and disadvantages of the systems, and compare yield and noise from alternative models. The WINEUR project and Warwick wind trails are based on 21 building mounted turbines each, while the Massachusetts trial is based on 19 small turbines in urban locations [79]. Both the Warwick and Massachusetts projects found that urban site conditions that reduce wind speed are not the sole reason for low energy production. The accuracy of manufacturers’ power curves, losses from balance-of-system components, and losses from additional site conditions (such as very close obstacles causing turbulence and wind shear), have also been identified as major causes. The balance-of-systems and effect of turbulence/wind shear are estimated to reduce energy production by 10–15% and 15–30%, respectively. The following figure shows both typical curves for different analysed turbines and the annual wind speed frequency distribution for above NPP respectively.

 

Figure 5.7: typical curves for different analysed turbines and the annual wind speed frequency distribution on NPP.

 

The following figure shows the estimated efficiency for each turbine in Edmonton NPP in on-roof project. This efficiency takes into consideration the different loss of efficiency due to mechanical and electronic losses in transmission, conversion, insects, ice, etc. The net delivered energy by the turbine should be considered for comparison of technologies, the development of the business case and any other study or comparison.

 

Figure 5.8: Total energy efficiency estimation for the analysed turbines considering the on-roof application in NPP. The average value, 20.5%, is shown as the red line.

 

-          Total efficiency higher than 20% is anticipated for efficiency specifications.

 

5.4.10           Costs

The overall cost for the wind turbine project is determined by the manufacturing costs, the amount of captured energy, the cost for site preparation and installation, the maintenance cost and the financing cost [40]. It is measured in $/kWh. Technical factors such as the efficiency of the turbine, the efficiency of drive train, generator and grid connection also have an important impact on the cost.

 

When comparing the manufacturing costs of VAWTs and HAWTs, consider that the HAWTs have been produced for a long time and are produced in large numbers. As result smarter and cheaper solutions and the large numbers produced decreases the price since parts can be mass produced. Furthermore, as the technology has matured it has been possible to scale up the HAWTs, lowering the cost per installed kW even more. No mass production of VAWTs exists.

 

The difference in costs between VAWTs and HAWTs for planning, producing, transporting and erecting a turbine and for operation and maintenance (O&M) is mainly governed by the different costs for producing the turbine and the costs for O&M with some exceptions; it might be easier to erect the lighter tower of a VAWT, and it might be easier to transport the shorter blades of a HAWT, whereas the curved blades for the Darrieus turbine is very difficult to transport.

 

The efficiency for VAWTs is expected to nearly reach efficiency values for HAWTs [40]. The design of the H-rotor is based on simplicity. By omitting a yaw system and the heavy nacelle and by having straight blades, the production costs are lowered even though the H-rotor usually has longer blades than a HAWT. For a Darrieus turbine, the blades are expensive to manufacture since they are both long and bent and sometimes twisted. The cost analysis made by Walters et al. [47] indicates that VAWTs could be cost competitive to HAWTs.

 

The following figure shows the range of cost per kilowatt nominal capacity:

 

 

Figure 5.9: Cost of wind project per kW of nominal capacity

 

 

5.4.11           On-roof downtown projects

Since the majority of the world’s population lives in urban areas, implementing wind turbines for electricity micro-generation for urban houses has the potential to make a significant contribution to renewable energy targets. Micro-generation at the single-building scale using roof-top wind turbines is one technology being used on urban houses increasingly in European cities and just starting in Canadian cities.

 

Typical roof-top turbine installations for houses are rated at 3.5 kW or less. In Alberta, a 2.5 kW nominal capacity turbine is enough to provide the consumed electricity for the average household. A study of 21 roof-top turbine installations in Europe under the WINEUR project has revealed that the reasons for installing turbines vary from educational (46%) and environmental (26%) to improving the organisational image (20%). Thirty percent of these turbines were installed in villages or country parks, while only 10% were installed in dense inner-city locations [79].

 

To date the low development of roof-top turbines in relationship with wind farms is related with the lower efficiency, high cost per nominal kW for the small turbines, particularities for each application, and a lack of policies that help with the development of the micro turbines market. All these barriers are being minimized over time with the introduction and development of new technology and adequate policies such as Alberta’s micro-generation regulation.

 

Computer simulations used to study wind flow in an urban area around an array of simple pitched-roof buildings, along with the effect of potential turbine mounting position on the turbine output, found that the behaviour of wind in a built-up area is different from that around an isolated house. For example, the speed-up effect as wind passes over the ridge of an isolated house is absent when the house is in an urban environment. Appendix L summarizes different on-roof projects around the world.

 

5.4.12           Decommissioning

Unlike many conventional energy generating sites, on-roof wind turbines do not require expensive decommissioning or remediation when they cease operation. Also, on-roof turbines are small turbines and their decommissioning does not require special considerations.

 

Decommissioning will occur if leases are not renewed at the end of the term. Full removal of all equipment and foundations and the site remediation will be completed, to the satisfaction of the landowner as stipulated in the lease agreement, and in compliance with all federal, provincial, municipal and building regulations.

 

6          Regulations

6.1       Public safety considerations

This section identifies potential health and safety risks to the public from the construction and operation of the Project.

 

Noise

With little consideration of low frequency noise standards, which vary from country to country, the inadequacy of Michigan’s wind turbine noise standard becomes apparent when reviewing general noise level standards

for community noise and wind turbine noise that have been adopted around the world. The Michigan Wind Guidelines states 55 dBA. Michigan Standards also exceed regulatory limits set in Denmark, the Netherlands, Germany and New Zealand, which have not been included here.

 

 

District type

Daytime limit [dBA]

Evening limit [dBA]

Night limit [dBA]

Rural

35

30

25

Sub-urban

40

35

30

Urban residential

45

40

35

Urban mixed

50

45

40

Table 6.1: ISO 1996-1971 Recommendations for Community Noise Limits

 

Icing

Icing presents an important concern due to the weather conditions for the turbine location. The lack of regulation about wind turbine icing presents more challenges for this project located in Edmonton.

 

Aircraft Routes

One of the major constraints for developing the on-roof project in Edmonton downtown is the aeronautical regulations due to the Edmonton City Centre Airport. NPP and SPP are in the protected zone for air traffic and the regulations introduce serious limitations in lighting, colour and maximum height.

 

 

Figure 6.1: view of Edmonton City Airport and NPP and SPP buildings

 

The minimum distance between NPP and the south runways of the airport is around 2,500 meters. This is the minimum required distance for many security navigation regulations. The analysis should carry on with precaution. The evaluation process has already started.

 

The authorization request should be completed for new structures only if:

·         The structure is within six (6) kilometers of the center of an aerodrome, or two (2) kilometers of a TC radar, radio navigation or radio communication antenna; or

·         The structure exceeds twenty (20) meters in height, including catenary wire crossings; or

·         The structure is within fifteen (15) meters and exceeds the height of a dominant structure already in place.

 

Lightning

Due to the height of the turbines, there is a potential for lightning strikes. Navigation Canada provides the guidelines for lighting.

 

6.2       Federal Regulations

NAV Canada: http://www.navcanada.ca/NavCanada.asp?Content=ContentDefinitionFiles%5CServices%5CANSPrograms%5CLandUseProposal%5Cdefault.xml

 

Transport Canada: http://www.tc.gc.ca/ontarioregion/civilaviation/aerodrome/documents/ObstructionclearanceForm.PDF

http://www.tc.gc.ca/CivilAviation/Regserv/Affairs/cars/PART6/images/g621s07.gif

http://www.tc.gc.ca/CivilAviation/Regserv/Affairs/cars/Part6/Standards/Standard621.htm

 

Aeronautic Act: http://laws.justice.gc.ca/en/A-2

 

6.3       Provincial Regulations

Micro Generator Application - Process & Guidelines: http://www.auc.ab.ca/aucdocs/programs/MicroGen/Micro_Generator_Application_July%2018.pdf

 

Micro-generation Regulation: http://www.auc.ab.ca/aucdocs/programs/MicroGen/Microgen_Regulation.pdf

 

FAQ: http://www.auc.ab.ca/aucdocs/programs/MicroGen/micro_gen_faq.pdf

 

Forms: http://www.auc.ab.ca/aucdocs/programs/MicroGen/Forms.doc

 

Wire Service Provider: http://www.ucahelps.gov.ab.ca/9.html

 

Alberta Transportation: http://www.transportation.alberta.ca/Content/docType329/Production/rdpapp.pdf

 

Hydro and Electric Energy Act: http://www.qp.gov.ab.ca/documents/Acts/H16.cfm?frm_isbn=9780779730209 http://www.qp.gov.ab.ca/documents/Regs/1983_409.cfm?frm_isbn=0773236775

 

Legal Land Description: http://www.servicealberta.gov.ab.ca

 

6.4       Municipal Regulations

The City of Edmonton bylaw 14600 states the following limit for noise generation:

·         Daytime decibel limit – non residential:

o   75 dBA between 7 a.m. and 10 p.m

o   80 dBA lasting for a total period of time not exceeding two hours in any one day; or

o   85 dBA lasting for a total period of time not exceeding one hour in any one day.

·         Overnight decibel limit – non residential:

o   60 dBA before 7 a.m. or after 10 p.m.

 

Based on the research done a wind turbine would not exceed these limits.

 

Municipal Affaires : http://municipalaffairs.gov.ab.ca/

 

Edmonton Airport:

http://webdocs.edmonton.ca/InfraPlan/ZoningBylaw/ZoningBylaw/Part2/Overlays/810A_(APO)_Airport_Protection_Overlay_Schedule_for_the_City_Centre_Airport.htm

6.5       Building Owner

Negotiations with the building owner should be started one the project is approved. The project adds value to the building (e.g. provide credit for LEED qualification), but studies should be carry on to the changes in static and dynamic load in the building.

 

7          Business cases

7.1       Scenarios

Four different scenarios are proposed for a comparative analysis:

-          The first scenario is called status-quo; it represents not developing any project and to promote MG through advertisement, brochures, etc. as is the current practice.

-          The second scenario is called on-roof H/VWAT (On-roof wind); it represents the development of on-roof project based on HAWT or VWAT technology on NPP and SPP buildings (preferably but not limited to).

-          The third scenario is called HWAT (Ground wind), it represents the development of windmill project on river ground.

-          The fourth scenario is called Solar Panel; it represents the development of on-roof project based on Solar Photovoltaic (PV) panels on NPP and SPP buildings (preferably but not limited to).

 

7.2       High level assessment

Researchers had studied, proposed indexes and assessed the different renewable sources of energy for electricity generation [29][30][48][49][50][51][52][53]. Some of these assessments could be applied for Alberta’s conditions in the comparison for this project. In [29] [30] the non-combustion based renewable electricity generation technologies were assessed against a range of sustainability indicators, using data obtained from the literature. The conclusion (Alberta conditions are usually worse for renewable electricity production), according to the second paper our electricity generation is:

 

Technology

Sustainable rankings

Wind

13

 

Hydro

16

 

Solar

20

 

Geothermal

21

 

Table 7.1: Sustainable ranking for different technologies

 

 

The conclusion of this paper shows that wind technology has the best ranking assessment, followed by Hydro, PV and Geothermal. PV has 54% worse ranking than wind technology for our climate and location. Wind technology also shows better index in Price, GHG emission, availability and limitations, efficiency, water consumption and social impact; the only index that PV overcomes wind is in land use.

 

Quite often citizens, journalists, policymakers and politicians are bombarded for information showing the useful of solar technologies, geothermal for power, etc; usually, the information does not include details which adapt the technology for Alberta conditions (sun radiation intensity, grid emission, depth of resources, etc). Alberta’s conditions are significantly worse for solar technologies than the average condition studied in the assessment, and these indexes show more differences in our country.

 

7.3       Solar Photovoltaic

PV technology is an excellent technology, but for very specials applications today. The future appears to be better if some milestones are reached and barriers overtaken for the development of the technology. Also, today this technology needs of external conditions to see it massively used; one of the most important is the increase of fossil fuel prices.

 

Nowadays, PV technology looks to be very expensive and inefficient for common application in comparison to other technologies, especially in Alberta (and Canada). PV systems offer the promise of clean and plentiful energy, but they suffer a large handicap in that their cost is still much too high. Nevertheless, during the 1980s and 1990s PV cell production has been increasing on average by more than 15% per year.

 

Appendix M provides details of solar photovoltaic technology analysis.

 

7.4       Comparison of alternatives and evaluation

7.4.1    Assess Impact

All scenarios must be developed in similar and real conditions in Alberta regions, focusing on downtown buildings in big cities. The magnitude of the evaluation is:

 

 

Negative

 

Positive

High

Medium

Low

Neutral

Low

Medium

High

-3

-2

-1

0

1

2

3

Table 7.2: Assess impact evaluation table

 

Where:

- High: impact is significant and stakeholders support and preparation are critical

- Medium: manageable impact to the stakeholders

- Low: minor impact to the stakeholders

- None: stakeholders will not be impacted

 

 

Subject

Stand-by

Solar Panels

On roof Wind

Ground

Wind

Energy use and conservation

0

1

2

1

Energy efficiency promotion

0

1

2

1

GHG emission reduction

0

1

2

2

DoE commitment and initiative

-1

2

3

2

Micro-business development

1

2

3

3

Show case for MG technologies

0

1

3

3

Quality investment

-3

-2

2

2

Risk

0

-1

-1

-1

Impact Score

-3

+5

+16

+13

Table 7.3: Assess impact evaluation for the different four alternatives

 

 

7.4.2    Risks Assessment

Risk assessment consideration:

·         Probability of risk:

o   High: highly likely to occur

o   Medium: likely to occur

o   Low: not likely to occur

·         Impact of Risk

o   High: significant impact to the project

o   Medium: impact the project

o   Low: impact is relatively minor to the project

o   None: will not impact the project

 

Impact

High

3

-3

-6

-9

Medium

2

-2

-4

-6

Low

1

-1

-2

-3

None

0

0

0

0

 

 

-1

-2

-3

 

Low

Medium

High

 

Probability

Table 7.4: Risk assessment table

 

Appendix N presents the detailed risk analysis for each alternative.

 

 

Risk Impact

Stand-by

Solar Panels

On-roof Wind

Ground Wind

Total Risk

-6

-26

-18

-18

Table 7.5: Risk assessment outcome for the four different alternatives

 

7.4.3    Cost/Benefit Analysis

RETScreen software, by NRCan, provides a comparison tool between Solar Panel and Wind alternatives. Appendix O presents the RETScreen Finanacial analysis output.

 

Re-directing promotion budget

Stand-by

Solar Panels

On-roof Wind

Ground Wind

Nominal capacity [kW]

na

8

8

8

Electricity generation [MW/y]

na

8.4

17

15

Total Initial Cost

~40,000

83,764

59,499

57,720

Annual Cost

0

220

300

300

Simple Payback [y]

na

54.1

17.2

16.1

Equity Payback [y]

na

35.4

14.2

13.4

Table 7.6: RETScreen summary for the ecominic comparison of the four alterantives

As Wind Turbines and Solar Panels contribute significantly to micro-generation promotion, business cases are developed where the 75% of the micro-generation funds for Stand-by alternative are used as promotion in the other alternatives.

 

Re-directing promotion budget

Stand-by

Solar Panels

On-roof Wind

Ground Wind

Nominal capacity [kW]

na

8

8

8

Electricity generation [MW/y]

na

8.4

17

15

Total Initial Cost

~40,000

53,764

29,499

27,720

Annual Cost

0

220

300

300

Simple Payback [y]

na

54.1

17.2

16.1

Equity Payback [y]

na

35.4

14.2

13.4

Table 7.7: Reasignation of funding for  the RETScreen summary for the ecominic comparison.

 

 

7.4.4    Comparison – Conclusions on alternative scenarios

The Assess Impact assessment shows that Wind Turbine is the better project in comparison to Solar Panels and Stand-by alternatives.

 

Assess Impact

Stand-by

Solar Panels

On-roof Wind

Ground Wind

Impact Score

-3

+5

+16

+13

 

The Risk Impact assessment shows that Stand-by alternatives has a lower risk, followed by Wind Turbine alternatives.

 

Assess Impact

Stand-by

Solar Panels

On-roof Wind

Ground Wind

Total Risk

-6

-26

-18

-18

 

Economic assessment shows that Wind turbine alternatives are abetter as business case in comparison to Solar Panels and Stand-by alternatives.

Economic assessment

Stand-by

Solar Panels

On-roof Wind

Ground Wind

Nominal capacity [kW]

na

8

8

8

Electricity generation [MW/y]

na

8.4

17

15

Total Initial Cost

~40,000

53,764

29,499

27,720

Annual Cost

0

220

300

300

Simple Payback [y]

na

54.1

17.2

16.1

Equity Payback [y]

na

35.4

14.2

13.4

 

In conclusion, the development of wind projects presents enormous advantages to Stand-by and Solar Panel alternatives; on-roof wind project presents a small advantage in comparison with ground wind project.

 

8          On-roof Wind Project

8.1       Alternatives

The project could be divided in mains stages:

 

 

Write RFP

 

 

 

 

Send the RFP to pre-selected companies

 

 

 

 

Evaluate proposals

 

 

 

 

Select the company to develop the project

 

 

 

 

Sign agreement

 

 

 

Measure weather conditions in the buildings

 

Start with the development of the project and construction of parts

 

 

 

 

 

Installation

 

 

 

 

SAT- Commissioning

 

 

 

 

Decommissioning

 

Figure 8.1: milestones in the development of the project

 

 

Four development alternatives for the project could be implemented:

1.       DoE: the project is managed and supervised by DoE. Staff in the DoE manage and supervise each of the tasks described above.

2.       Eng: the project supervised by DoE by contracting an engineering company. The company manages and supervises each of the tasks above. Staff in the DoE supervises the engineering firm.

3.       Com: the project is supervised by DoE under pre-agreement with a turbine builder or its representing company. Agreement with a specialized company to develop the last four tasks above. Staff in the DoE selects and supervises the company.

4.       Par: the project is supervised by DoE under pre-agreement with a turbine builder or its representing company. Staff in the DoE supervises the company. The company will recover part of the investment by the saved energy during the lifetime of the project. The capital expenditure will be minimal for the GoA.

 

 

All alternatives present an opportunity for the company which develops the project to promote their products and solution; this advantage is not analysed in the business case and it is part of the foreseen negotiations with the company providing the technology.

 

8.2       Assess Impact

The comparison for the three alternatives is:

 

Subject

DoE

Eng

Com

Part

Wrote RFP

0

1

2

2

sent the RFP to pre-selected companies

1

0

2

2

signed of agreement

2

2

3

3

Measured weather conditions in the buildings

0

0

2

2

Project development

1

2

3

3

Installation

1

2

3

3

SAT- Commissioning

0

0

1

2

Project time

0

1

3

3

Government investment

0

0

2

3

Continue efficiency

1

1

2

3

Decommissioning

0

0

0

0

Total

+6

+9

+23

+26

Table 8.1: Assess impact outcomes for the four alternatives developing the on-roof project

8.3       Risk Assessment

The risk assessment details could be seeing in Appendix Q. The summary is presented here:

 

 

DoE

Eng

Com

Part

Total Risk

-43

-37

-26

-18

Table 8.2: Risk impact outcomes for the four alternatives developing the on-roof project

 

8.4       Business cases

Appendix R presents the business cases without consideration of the induced business development and cost of manpower for the DoE.

The following analysis considers several issues:

·         Cost of manpower, administrative and professional, for the GoA in the development, supervision, administration and inspection of the project;

·         The revenue generated by the promotion of the technology across the province. One of the most important goals for this project is micro-generation promotion in Alberta. This promotion stimulates the development of projects, which generate revenue for the government in two ways: corporate income tax and personal income tax through workers.

Considering:

·         VAWT cost turbine (HAWT has a capital cost 5 to 15% lower) 

·         Nominal Capacity: 6 kW

·         Turbines: 2, one on each building

·         Net Efficiency: 20%

·         Cost of the project: 8,570 $/kW

·         Maintenance cost: 800 $/y (DoE and Eng); 400 $/y (Com) and 250 $/y (Part)

·         Inflation: 2.3%/y

·         Increase COE : 2.3%/y

·         Rate of Return: 9%

·         Final COE : 0.12 $/kW

·         Life time: 25 years

·         Decommissioning: $7500 plus $1250/kW

·         Incenting the development of 10 micro-generation projects per year: