Feasibility Study of PV Covered Walkways and Other Areas on TESC Campus

By Hanna Vander Woude and Alan Deufel

Abstract

The primary goal of our research was to determine the areas on Evergreen’s campus that could support photovoltaic (PV) covered walkways. The advantages of mounting PV panels on top of a walkway is that they would be multi-purpose: protection from weather, energy production, and education. We measured the areas of four different possible sites on campus and calculated the potential energy production over the course of a year using Pathfinder software as well as the effective unshaded area of each site. We came to the conclusion that

Introduction

We undertook this study because the addition of photovoltaic covered walkways to the campus would serve multiple functions thereby making the panels a more economical option for energy production. The photovoltaic panels would serve as protection from rain as students make their way around campus and the highly visible nature of PV covered walkways makes them an excellent education tool. Although PV arrays mounted on the rooftops of Evergreen’s buildings might provide a more traditional and productive spot for gathering solar energy, the limited visibility of an array in this location limits their rich educational potential.

Methods and Materials

We chose the sites to measure by considering the visibility of the site, how a walkway or covering would fit into the aesthetics of the surrounding landscape, the degree of shading we expected the panels would receive, and the usefulness that would be gained from having this covering or walkway as a protection from weather. We decided to measure four different sites: the SEM II walkway, the Market Place/CRC walkway, the CAB Patio, and the CAB bicycle area. To find the total area of each site we used a 25 ft tape measure.

We used a SolarPathfinder to measure the expected insolation of the possible sites over the course of a year. We took a picture of the SolarPathfinder device at each site and uploaded these pictures to the SolarPathfinder software (for a more detailed methodology see the SolarPathfinder Report). We used the software to create a report detailing the solar radiation at each considered site.

Results

Figure 1. Possible locations for visible PV arrays on TESC campus. Site A is the SEM II walkway, Site B is the CRC/Market Place walkway, Site C is the CAB bicycle area, and Site D is the CAB Patio.

Site A

Site B

Site D

Site C

Results

Table 1. Site AreasTable 1. Site AreasTable 1. Site Areas

Site Location Area (sq. ft.)

A SEM II Walkway - Part 1 2238

SEM II Walkway - Part 2 60

B CRC/Market Place Walkway - Option 1 3602

CRC/Market Place Walkway - Option 2 2853

CRC/Market Place Walkway - Option 3 749

C CAB Bicycle Area 618

D CAB Patio 1310

Table 2. Solar Production Efficiencies at Each siteTable 2. Solar Production Efficiencies at Each siteTable 2. Solar Production Efficiencies at Each siteTable 2. Solar Production Efficiencies at Each site

Site Location Actual shaded solar radiation with compass azimuth at 158.3 / Ideal

Solar Radiation

Effective unshaded area (sq. ft.)

A SEM II Walkway

53% 1218

B CRC/Market Place Walkway

? ?

C CAB Bicycle Area

73% 451

D CAB Patio 84% 1100

Figure 2. Site A. SEM II Walkway Part 1. Figure 3. Site A. SEM II Walkway Part 2.

Figure 4. Site B. CRC/Market place Walkway Option 1.

Figure 5. Site B. CRC/Market place Walkway Option 2.

Figure 6. Site B. CRC/Market place Walkway Option 3.

Figure 8. Site D. CAB Patio. Figure 7. Site C. CAB Bicycle Area.

Figure 9. SolarPathfinder at Site A. Figure 10. SolarPathfinder

at Site C. Figure 11. SolarPathfinder at Site D.

We found that the CRC/Market Place walkway under both option one and two had the largest areas with 3602 sq.ft. and 2853 sq. ft., respectively. SEM II came in as the next largest with an area of 1218 sq. ft. However, the CAB patio had the highest percentage of actual shaded solar compared to ideal solar radiation at 84%. We used these two sets of measured values to find the effective unshaded area for each site. Our results showed that the SEM II walkway (parts 1 and 2) had an effective unshaded area of 1218 sq.ft. The CAB Patio had an effective unshaded area of 1100 sq. ft.

Discussion

After analyzing the data we have concluded that the CAB Patio is our first recommendation for a PV covered area. Although the area isn’t as large as the SEM II walkway, it has an effective unshaded area that is almost as large. The smaller area would also mean that the PV installation would be smaller and therefore cost less. In addition to the benefit of capturing solar energy, the array would be highly visible from the center of campus and it would add more usable seating area to the CAB during the many rainy months in Olympia.