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So lar Access and Shade Report

City of Escanaba Solar Escanaba, MI

November 22, 2017

Prepared For:

Solar Access and Shade Report

City of Escanaba Solar

Delta County Airport

3300 Airport Road

Escanaba, MI 49829

Prepared for:

City of Escanaba

410 Ludington St.

Escanaba, MI 49829

Prepared by:

Westwood Professional Services

7699 Anagram Drive

Eden Prairie, MN 55344

(952) 937-5150

Solar Access and Shade Report 11/22/2017

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CONTENTS

EXECUTIVE SUMMARY .................................................................................................................... 1

INTRODUCTION ............................................................................................................................... 1

SOLAR ACCESS AND SHADING REVIEW........................................................................................... 3

Skylines 01, 05, 07, 10, 16, 19, 21 ................................................................................. 3

Skyline 13 ...................................................................................................................... 4

Skylines 02, 03, 04, 06, 08, 09, 11, 12, 14, 15, 16, 17, 18, 20, 22 ................................. 4

CONCLUSIONS ................................................................................................................................. 4

FIGURES

Figure 1: Skyline Locations ............................................................................................................. 2

Figure 2: Sky01 sun path and solar access table ............................................................................ 3

Figure 3: Evergreen tree south of Sky13 (from Google Street View) ............................................ 4

TABLES

Table 1: Skylines ............................................................................................................................. 2

APPENDICES

Appendix 1: Solar Access and Shade Report – Single Axis Tracker Appendix 2: Solar Access and Shade Report – Fixed-Tilt


1

EXECUTIVE SUMMARY

The purpose of this report is to describe the methods and analysis of Westwood’s solar shading analysis performed for the City of Escanaba Solar Project (Project) near the Delta County Airport in Escanaba, Michigan.

On the 1st of November 2017 (with full tree leaf-on coverage), Westwood sent staff into the field to collect data on potential shading features in the Project area. These features were primarily trees. Westwood used a Solmetric SunEye 210 to capture solar access and shading features for two types of potential solar installations: fixed-tilt (FT) and single-axis tracker (SAT).

The results of the SunEye data collection, for both FT and SAT, show that the potential Project location to be generally free from shading, with an average solar access percentage between 99-100%, with 100% equaling full sun with zero shading. Generally, the areas closest to the trees south of Airport Road are the most prone to shading, however even at these locations the effects are minimal. The south-central portion of the site, around Skyline 13 (described below), appears to have the highest shading loss with wintertime solar access approaching 76% for SAT and 85% for FT.

INTRODUCTION

Solar access is defined by Solmetric as:

The insolation available, accounting for shade divided by the total insolation available without shade, as a percentage. Insolation in both cases accounts for the specific tilt and orientation of the surface and is only affected by shading obstructions within the field of view of the [measurement] surface. Solar access of 100% implies that there are no shading obstructions within the field of view on the surface.

Solar access data was captured at multiple locations, to understand how shading features impact the project at various locations, shading feature sizes, and distances from shading features. Westwood captured a total of 22 solar access readings, called “skylines,” at locations around the Project site, as shown in Figure 1.

Westwood set up the SunEye for the specific Project location and Project designs:

Single-axis tracker oriented 180° due south at a flat 0° tilt and with a 60° maximum rotation to the east and west.

Fixed-tilt solar rack oriented 180° due south at a 35° tilt, which is ideal for this latitude.


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This provides greater accuracy to the analysis, as different project designs (such as tracker vs. fixed tilt) will have different solar access windows which are affected by shading.

Figure 1: Skyline Locations

To capture this data, the SunEye operator stands with the SunEye at each location, and using the tool’s fisheye lens, takes a 360° photograph of the sky and any shading features. The path of the sun is overlaid onto this photo, creating an image that the SunEye software uses to determine specific shading times and locations. The skylines produced for this report are:

Table 1: Skylines

Skyline Name Description Latitude Longitude

Sky01 South portion of site along Airport Rd. 45.717620° -87.098140°

Sky02 Central portion of site 45.717842° -87.098152°

Sky03 North portion of site 45.718151° -87.098328°

Sky04 NE corner of site 45.718376° -87.098396°












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All of the skylines included in this report, along with camera images and tables (for use with production modeling) are included as Appendices 1 and 2 to this report.

The following Section will review and comment on specific skylines and their solar access.

SOLAR ACCESS AND SHADING REVIEW

Skylines 01, 05, 07, 10, 16, 19, 21

These skylines are located closest to the road on the south side of the project. South of the road are deciduous and coniferous trees. These skylines show minor potential shading from the trees to the south. Even this potential shading is limited to the winter months, when solar energy generation is generally at its lowest point. The summer months all show 100% solar access, when energy production is peaking. The figure below is an excerpt from the report in Appendix 1, showing the fisheye image and path of the sun, along with the table of monthly solar access. A slight dip can be seen in January, November, and December, due to minor shading from the trees.

Figure 2: Sky01 sun path and solar access table


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Skyline 13

This skyline is located on the south side of the project at the center of the site. South of the road are deciduous and coniferous trees. In particular, a large evergreen tree appears to be causing some shading during the winter months at this location. This location registers the most shading of any location on-site, with winter solar access averaging 95%, and dipping down to 85% (FT) and 76% (SAT) in December. Regardless, the annual average solar access remains high at 98%.

Figure 3: Evergreen tree south of Sky13

(from Google Street View)

Skylines 02, 03, 04, 06, 08, 09, 11, 12, 14, 15, 16, 17, 18, 20, 22

The remaining skylines from the interior of the site show wide-open solar access throughout the year, from 99-100% full sun without shading.

CONCLUSIONS

From reviewing the SunEye data collected on site, it appears that the Project site is largely free from shading caused by trees. It is important to note that this report provides data from selected locations around the site and may not represent shading and solar access at every location in the Project. Additionally, future conditions, such as tree growth, may cause a change to solar access and shading conditions.

Solar access does not necessarily translate directly into energy production gains and losses. That is, a SunEye capture with a 95% solar access does not necessarily mean that area will produce 95% of its total possible energy production. The solar access data captured by the SunEye must be imported into energy modeling software for use in production calculations, and other factors may have an effect on overall Project energy production.

Please feel free to contact us if you have any questions regarding this report.

Solar Access and Shade Report11/20/2017

For:City of Escanaba - Fixed-Tilt

Escanaba, MI

By:Westwood Professional Services

7699 Anagram DriveEden Prairie, MN 55344

888-937-5150

Measurements made by Solmetric SunEye™ -- www.solmetric.com

Session Properties

Name Escanaba FixedCreation Date 11/1/2017 11:47Note (none)

Location45.7°N, 87.1°WMag Dec: 5.3°WTime Zone: GMT-06:00

Solar access averages of 22 skylines in this sessionSkylines Averaged: Sky01, Sky02, Sky03, Sky04, Sky05, Sky06, Sky07, Sky08, Sky09, Sky10, Sky11, Sky12, Sky13, Sky14,Sky15, Sky16, Sky17, Sky18, Sky19, Sky20, Sky21, Sky22

Annual May-Oct Nov-Apr99% 100% 99%

TSRF averages of 22 skylines in this session: 99%

Sky01 -- 11/1/2017 11:53 -- (no skyline note)

Panel Orientation: Tilt=35° -- Azimuth=180° -- Skyline Heading=184°Solar Access: Annual: 100% -- Summer (May-Oct): 100% -- Winter (Nov-Apr): 99% TSRF: 99% -- TOF: 99%

Solar Access and Shade Report11/20/2017

For:City of Escanaba - Single Axis Tracker

Escanaba, MI

By:Westwood Professional Services

7699 Anagram DriveEden Prairie, MN 55344

888-937-5150

Measurements made by Solmetric SunEye™ -- www.solmetric.com

Session Properties

Name Escanaba TrackerCreation Date 11/1/2017 11:48Note (none)

Location45.7°N, 87.1°WMag Dec: 5.3°WTime Zone: GMT-06:00

Solar access averages of 22 skylines in this sessionSkylines Averaged: Sky01, Sky02, Sky03, Sky04, Sky05, Sky06, Sky07, Sky08, Sky09, Sky10, Sky11, Sky12, Sky13, Sky14,Sky15, Sky16, Sky17, Sky18, Sky19, Sky20, Sky21, Sky22

Annual May-Oct Nov-Apr99% 100% 99%

TSRF averages of 22 skylines in this session: 116%


Panel Orientation: 1 Axis -- Tilt=0° -- Azimuth=180° -- Tracking Limit=60° -- Skyline Heading=182°Solar Access: Annual: 100% -- Summer (May-Oct): 100% -- Winter (Nov-Apr): 100% TSRF: 117% -- TOF: 117%

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