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Solar Glare Analysis Report – Alberta Solar One Morgan Solar Inc., County of Forty Mile, Alberta
Version 2.0 – Issued for Use
Confidential
12 September 2018
Delivered to: Samuel Buckstein, Morgan Solar Inc.
Solas Energy Consulting Inc. Suite 119, 2-2009 33 Ave SW Calgary, Alberta T2T 1Z5
Phone: 403-454-9463 Email: [email protected] Web: www.solasenergyconsulting.com
Alberta Solar One Glare Analysis
Confidential
12 September 2018 Page i
Acknowledgement
Prepared by: Leonard Olien
Jason Mah
Paula McGarrigle
Document Purpose
This report provides an assessment of glare hazard from the Alberta Solar One solar farm in the
County of Forty Mile, Alberta, Canada.
Document History
Alberta Solar One Glare Analysis
Version Date Comments
1.0 12 August 2018 Issued for Review
2.0 12 September 2018 Issued for Use - updated analysis to include limitations to tracking rotation
Disclaimer
While this document is believed to contain correct information, Solas Energy Consulting Inc. (“SOLAS”) does not make any
warranty, either expressed or implied, nor assumes any legal liability or responsibility for accuracy, completeness,
methodology, usefulness, reliability, or current status of any material contained in this document (“Report”), nor shall SOLAS
assume any liability with respect to any matter or information referred to or contained in the Report, nor shall any person
relying on the Report (“Recipient”) or any party to whom the Recipient provides the Report or information have any claim
against SOLAS arising out of such Report. The interpretation of this or any other data or report related to this project is solely
the responsibility of the client.
Alberta Solar One Glare Analysis
Confidential
12 September 2018 Page ii
Table of Contents
1 INTRODUCTION ............................................................................................................................................ 4
2 PROJECT DESCRIPTION ................................................................................................................................. 5
3 PROJECT ASSUMPTIONS ............................................................................................................................... 7
4 GLARE REGULATIONS AND RECEPTORS ......................................................................................................... 8
5 GLARE PREDICTION METHOD ..................................................................................................................... 11
6 ANALYSIS RESULTS ..................................................................................................................................... 13
7 CONCLUSIONS AND DISCUSSION ................................................................................................................ 14
Table of Figures
Figure 1: Location of the Project: Alberta Solar One and proximity to Burdett and Highway 3.................................... 5
Figure 2: Project Boundary and Proposed Alberta Solar One Array .............................................................................. 6
Figure 3: Alberta Solar One Array with Observation Points Identified .......................................................................... 9
Figure 4: Reflected Light and Angle of Incidence on the PV Module Illustration ........................................................ 11
Table of Tables
Table 1: Description of Observation Points ................................................................................................................. 10
Table of Appendices
Appendix A ForgeSolar Modelling Assumptions
Alberta Solar One Glare Analysis
Confidential
12 September 2018 Page iii
Glossary
Abbreviation Term
After-image Visual image that persists after the stimulus that caused it has stopped.
AUC Alberta Utilities Commission
Azimuth Horizontal angle of the Sun around an object. North is 0°, east is 90°, south is 180°, and west is 270°.
FP Flight path
kWDC Kilowatts Direct Current
mrad Measure of angle, 1/1000th of a radian
MWAC Megawatts Alternating Current
MWDC Megawatts Direct Current
OP Observation point
Subtended Angle Size of an object divided by the distance from the observer.
WDC Watts Direct Current
Alberta Solar One Glare Analysis
Section 1, Introduction
Confidential
12 September 2018 Page 4
1 INTRODUCTION Morgan Solar Inc. (Morgan Solar) is developing a utility-scale solar photovoltaic project called
Alberta Solar One (Project) in southeastern Alberta. The Project is located north of Highway 3,
approximately four kilometres west of Burdett, Alberta. The Project is expected to have a total
capacity of 9.5 MWAC.
Photovoltaic (PV) solar modules are designed to convert sunlight into electricity; however, up to
10 percent of the sunlight may be reflected into the surrounding areas1. In certain situations, the
reflected sunlight can produce glint (a momentary flash of bright light) and glare (a continuous
source of bright light) that may result in an ocular impact to individuals.
Solas Energy Consulting Inc. (Solas) was retained by Morgan Solar to conduct a glare analysis for
observation points at nearby residences, and from major transportation infrastructure near the
Project. Solas performed an analysis for residential locations, major roadways, and the rail line near
the Project.
This report documents the potential for solar glare from the Project at the observation points.
1 Solar Glare Hazard Analysis Tool (SGHAT) User’s Manual v 1.0, Ho and Sims, Sandia National Laboratories,
2013.
Alberta Solar One Glare Analysis
Section 2, Project Description
Confidential
12 September 2018 Page 5
2 PROJECT DESCRIPTION The 9.5 MWAC Project is a ground-mounted, dual-axis tracking solar concentrating photovoltaic
(CPV) array using new proprietary technology. The Project will be located on agricultural land in
the west half of NE-21-10-12-W4M. The approximate location of the Project is shown in Figure 1.
The Project will be connected to the distribution system, and the electricity produced will be sold
to the grid. Construction is expected to occur in 2018-2019.
The Project is 400 metres west of Range Road 123, one kilometre (km) north of Highway 3
(Crowsnest Highway) and the Canadian Pacific Railway, four kilometres west of Burdett, and 7.5
kilometres south of the South Saskatchewan River. The Burdett 368S substation is three kilometres
southeast of the Project. There are residences on the land around the Project, which is relatively
flat with few trees.
There are no registered helipads or airport landing strips within three kilometres of the Project.
Figure 1: Location of the Project: Alberta Solar One and proximity to Burdett and Highway 3
Figure 2 outlines the Project area in red and shows the solar CPV array as the dark interior area.
Alberta Solar One Glare Analysis
Section 2, Project Description
Confidential
12 September 2018 Page 6
Figure 2: Project Boundary and Proposed Alberta Solar One Array
Alberta Solar One Glare Analysis
Section 3, Project Assumptions
Confidential
12 September 2018 Page 7
3 PROJECT ASSUMPTIONS The Project is located on approximately 76 acres of land. Solas used multiple sources to determine
the site elevation, including a topographic site plan provided by Morgan Solar. A change of grade
may affect the results from the glare analysis.
The Project will use Morgan Solar’s 335-WattDC “SimbaX” solar CPV modules and “Savanna” dual-
axis tracking racks. Three CPV modules will be mounted on each tracker. Dual-axis trackers allow
modules to directly face the sun at all times, rotating to a maximum of 60 degrees from horizontal.
At night, the modules return to the horizontal orientation to enter stow mode. Stow mode is also
engaged during high wind events, positioning the short edge as the leading edge facing into the
wind. SimbaX modules have a glass surface that has anti-reflective coating. While the technology
associated with the SimbaX modules differs from standard solar PV, the SimbaX module’s use of a
glass surface with anti-reflective coating is consistent with that of solar PV. In the vertical position,
the modules will be 1.15 metres above the ground at the bottom, extending to a height of 3.15
metres at the top2. Approximate locations for the solar array vertices were used in the analysis as
exact coordinates were not available.
The model assumes the reflective surface lies in a plane defined by the array vertices, so the
analysis was completed at the top and bottom elevations to determine glare due to different
parts of the modules. The analysis was also run at an intermediate elevation of 2.15 metres to help
identify trends in the frequency and size of glare. The analysis was completed as if the Project will
be installed as a single array.
Detailed input parameters and assumptions can be found in Appendix A.
2 Data provided by Morgan Solar
Alberta Solar One Glare Analysis
Section 4, Glare Regulations and Receptors
Confidential
12 September 2018 Page 8
4 GLARE REGULATIONS AND RECEPTORS At the time of writing, there are no Canadian federal, provincial, or municipal regulations or
requirements regarding glare from solar projects. In the United States, the Federal Aviation
Administration stipulates that any glare occurring along an aircraft’s flight landing path must have
a low potential of producing after-image3. Glare outside of 50 degrees of the pilot’s line of sight is
not considered a risk.
Alberta Transportation requires developers to obtain a roadside development permit for
construction of structures near provincial highways. If a proposed development is to be located
within 300 metres of a provincial highway right-of-way, or within 800 metres of the centre point of
an intersection between a provincial highway and another public road, a roadside development
application must be made to Alberta Transportation. The proposed Project will not be located
within these boundaries, so it will not require a roadside development permit from Alberta
Transportation.
Transport Canada publication TP1247E Aviation Land Use in the Vicinity of Aerodromes offers
guidelines useful for glare reports. The guidelines indicate “The analysis of glare should involve a
review of the position of the aircraft for both landing and take-offs as well as performing a circling
approach… The designer should review the positioning and orientation of the panels in relation
to the control tower to ensure that adverse reflection will not be produced.”
Solas completed a review of registered airstrips and helipads within three kilometres of the Project,
and did not find any; therefore, Solas did not evaluate flight paths near the project. Solas selected
observation points to assess the potential glare on nearby residents and vehicle routes.
Observation points for residences near the Project were evaluated at an elevation of 1.83 metres
above ground level to mimic an individual standing at a window on the main floor. Observation
points on roads were evaluated at an elevation of 1.22 metres to mimic a driver sitting in a small
truck or passenger vehicle. Solas evaluated railway observation points at an elevation of 4.27
metres above ground level to simulate the conductor inside the cab of the train.
Solas analyzed the potential for glare at the observation points shown in Figure 3. Nine observation
points were evaluated.
3 https://www.federalregister.gov/documents/2013/10/23/2013-24729/interim-policy-faa-review-of-solar-
energy-system-projects-on-federally-obligated-airports
Alberta Solar One Glare Analysis
Section 4, Glare Regulations and Receptors
Confidential
12 September 2018 Page 9
Figure 3: Alberta Solar One Array with Observation Points Identified
Table 1 lists the observation points used in the analysis. The table also identifies the number of
vehicles travelling along Highway 3 south of the Project.4,5
4 http://www.transportation.alberta.ca/mapping/2017/TM/00123080.pdf 5 http://www.transportation.alberta.ca/mapping/2017/TM/70000622.pdf
Alberta Solar One Glare Analysis
Section 4, Glare Regulations and Receptors
Confidential
12 September 2018 Page 10
Table 1: Description of Observation Points
Observation
Point Number
Location Description Daily Traffic
(Number of Vehicles)
OP1 Residence Main floor (1.83 metres) N/A
OP2 Residence Main floor (1.83 metres) N/A
OP3 Residence Main floor (1.83 metres) N/A
OP4 Residence Main floor (1.83 metres) N/A
OP5 Highway 3 Eastbound 3,500
OP6 Highway 3 Westbound 3,640
OP7 Railway Approaching Range Rd 124 from the
west
N/A
OP8 Railway Approaching Range Rd 122 from the
east
N/A
OP9 Residence Main floor (1.83 metres) N/A
Alberta Solar One Glare Analysis
Section 5, Glare Prediction Method
Confidential
12 September 2018 Page 11
5 GLARE PREDICTION METHOD The impact of glare depends on the interaction between the position of the sun, the tilt of the
solar modules, the reflectivity of the modules’ surface, the size of the project, and the relative
location of the driving path or the observer. Solas did not consider the screening effect from
existing or proposed hedgerows or other objects in this evaluation.
The sun’s position is described using the angle of elevation and solar azimuth. The angle of
elevation is the angle between the horizon and the centre of the sun. The azimuth is measured as
the angle from true north in a clockwise direction.
Solas performed the glare analysis using the ForgeSolar GlareGauge6 software tool. This tool uses
project inputs and solar positioning calculations to determine if glare will occur at identified
observation points. If glare is found, the tool calculates the retinal irradiance (brightness) and
subtended angle (size divided by distance) of the glare source. These two factors predict ocular
hazards ranging from temporary after-image to retinal burn. Minor topographic features are not
always identified in GlareGauge due to the resolution of the topographic contours from Google
Earth.
“Green” rated glare indicates a low potential for after-image, “yellow” rated glare indicates the
potential for after-image exists, and “red” rated glare indicates the potential for retinal damage.
Glare that is beyond 50 degrees from a driver’s line-of-sight does not constitute a safety hazard.7
The amount of light reflected by a solar module depends on the sunlight’s angle of incidence at
the module as illustrated in Figure 4.
Figure 4: Reflected Light and Angle of Incidence on the PV Module Illustration
6 Copyright, Sims Industries, 2015 7 SGHAT_Users_Manual_v2-F.pdf
Alberta Solar One Glare Analysis
Section 5, Glare Prediction Method
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12 September 2018 Page 12
Approximately 10 percent of sunlight is reflected from a solar module without anti-reflective
coatings on average8, which is about the same as open water9. Anti-reflection coating on the
solar module can reduce the reflection to one to two percent on average. The software models
the reflectivity for each angle of incidence based on experiments Sandia National Laboratories
performed for a variety of different module constructions10. Very little light is reflected when the
sun is nearly perpendicular to the module, but more light is reflected when the sun is at a shallow
angle to the module.
Solas uses Google maps to define the location and size of the CPV arrays, characteristics of the
CPV array, and position of observers.
5.1 Limitations of the Model This analysis aims to provide an indication of the glare that may be produced by the proposed
solar CPV array. The prediction methods employed in the analysis have uncertainty. The following
lists some of the limitations inherent in the analysis.
• The base model assumes clear skies at all times. The model does not use historical weather
pattern data. This results in a total cumulative duration of glare that is likely higher than
what will occur over the course of a year.
• Shading is not considered in the model.
• Obstructions such as foliage, structures, and hills between the arrays and observation
points are not modelled by ForgeSolar’s GlareGauge software tool.
o Separate analysis can be performed to evaluate the impact of topographical
features available in Google Earth on the predicted glare.
▪ The land surrounding the Project is flat, so topography will not likely affect
the results.
o The impact of trees and foliage is extremely variable, so it is not considered.
• Ocular and perceived hazards differ from person to person, depending on multiple
environmental, optical, and human factors.
• Changes in site and array elevation from the assumptions may change the results of the
analysis.
• The model assumes the use of conventional solar PV modules, which may have different
reflective characteristics when compared with Morgan Solar’s solar CPV modules.
• The model does not place a limit on the rotation of dual-axis trackers. Solas has manually
calibrated the results to ensure that the angle beyond 60 degrees is not permitted. Glare
results beyond 60 degrees have been removed.
8 Lasnier and Ang, 1990, Photovoltaic Engineering Handbook. Taylor & Francis, New York. 9 US EPA, 2013, AERSURFACE User’s guide, EPA-454/B-08-001. 10 Sandia National Laboratories, 2014, Solar Glare Hazard Analysis Tool (SGHAT) User’s Manual v. 2F, Appendix
E
Alberta Solar One Glare Analysis
Section 6, Analysis Results
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12 September 2018 Page 13
6 ANALYSIS RESULTS The Project does not reveal any red-grade glare.
Solas identified yellow-grade glare at the residence (OP9) northwest of the Project using the
GlareGauge model results. Solas calibrated the model results with the solar PV tracking limits of
60 degrees from horizontal. The final result indicates that glare occurrence will be eliminated at
OP9 as a result of tracker rotation being limited to 60 degrees from horizontal. Solas expects that
reflected light will therefore pass above the residence at OP9 for the associated sun elevations.
Alberta Solar One Glare Analysis
Section 7, Conclusions and Discussion
Confidential
12 September 2018 Page 14
7 CONCLUSIONS AND DISCUSSION Based on the assumptions, the results of the analysis indicate that the Project is likely free of hazards
due to glare at the observation points evaluated. Residents near the Project, drivers using
Highway 3 (Crowsnest Highway), and trains passing south of the Project will not likely experience
glare from the array based on the assumptions used in this analysis.
Based on the information associated with the geographic configuration of the solar modules, the
Project has a low potential to result in hazardous glare conditions. Changes to the Project layout
or specifications will affect the results of the analysis.
These results are based on the assumptions provided by the Client. Should any one of these
assumptions be altered over time, the results of this glare analysis are considered invalid and will
need to be revised.
Alberta Solar One Glare Analysis
Section 7, Conclusions and Discussion
Confidential
12 September 2018 Page 15
Appendix A ForgeSolar Modelling Assumptions
Axis tracking: Dual
Module material: Smooth glass with Anti-Reflective coating
Vary reflectivity with sun position? Yes
Ground elevation: 798 metres to 801 metres
Height above ground: Assessed at 1.15 metres, 2.15 metres, and 3.51 metres
Maximum Tilt Angle: 60 degrees from horizontal