First U.S. Urban Vertical Bifacial Solar Installation Completed in California
As urban congestion rises and commercial real estate becomes more confined, so can the space for solar PV in such environments. Solar can still produce power in tighter project footprints, however, by angling it to a vertical position.
Racking maker Sunzaun, earlier this year, completed what it thinks is the first vertical bifacial solar installation in an urban business setting in the United States at Bodhi Hot Yoga & Fitness in San Rafael, California.
Addressing Energy Costs for All-Electric Businesses
Co-owners Beau Keeve and Katie Egan created a company and a community, rooted in health and movement. They’re running an all-electric firm and have seen the escalating challenges of increasing energy expenses. Their monthly power expenses went from a few hundred dollars to over $2,000 since the infrared heating and humidity systems depended completely on the grid.
Conventional solar was out of the question, given the structurally complicated rooftop and the parking lot where every spot was critical. “We are using vertical bifacial solar to turn a business liability into a sustainable asset by converting their parking perimeter into a power source,” Sunzaun suggests.
The project consists of 16 bifacial panels, 8 to 9 ft tall, mounted vertically along the perimeter of the studio’s rear parking lot.
Commercial property roofs in metropolitan areas might be restricted in size and physically complex. Zoning constraints, joint building ownership, and municipal approval procedures add to the friction. That means many urban firms that want to go solar simply can’t access traditional installation channels.
Why Bifacial and Why Vertical?
Vertical bifacial solar is a proven solution for agricultural applications in Europe, where the panels are put vertically on the perimeters of the fields for dual land use. The method works because bifacial panels harvest light on both sides – direct irradiance on one side and reflected or diffuse irradiance on the other. They are north-south oriented and may provide useful energy all day, with peak production leaning towards morning and evening hours instead of centered around midday.
What had not been proved was whether this strategy could operate in a dense urban context where buildings, trees, and paved surfaces influence irradiance, and local permission complicates things further.
In the instance of Bodhi, a portion of the studio’s outside wall near the panels was painted white to see whether surface reflection might appreciably boost yield on the back face of the bifacial modules. Preliminary information on this variable will influence future urban installations where reflecting surfaces – building facades, paved lots, painted walls – might be intentionally integrated into system design.
“I think we’re the first … in an urban setting to do it in the U.S.,”
Keeve added.
Practical Lessons from Installation
The solar project at Bodhi took about 10 days to build, a little longer than the initial estimate of five days. City permits, utility coordination, and site logistics were the responsibility of the team, with just a little input from the property owner.
“The system was designed to balance energy costs in a tight urban setting and required careful integration with existing electrical infrastructure and meticulous site logistics,”
said Craig Dinsdale, chief performance officer of Sunzaun.
“Construction went ahead with few problems, despite these issues.”
Preserving space is a primary problem for any urban parking lot construction. This time, there were no parking spaces lost. The bottoms of the panels were protected by bollards, and the owners called the final installation an attractive enhancement to the site, serving visually as a contemporary perimeter fence.
The studio’s solar power is expected to save $5,000-10,000 a year.
Broader Implications for Urban Solar Deployment
Urban business buildings are an underserved area for solar deployment, partly because standard methodologies don’t meet their physical or legal restrictions. Another approach is vertical bifacial systems which use perimeter space rather than rooftop area and may be installed without disturbing day-to-day activities.
San Rafael is north of San Francisco in Marin County, a neighborhood with strong environmental values, significant fire season danger, and a business corridor that is becoming denser.
“We’re in this for the long haul, and to see this community prosper and grow,”
Egan added.
“Sunzaun was us putting our foot forward, putting us on the map with that.
Sunzaun will be monitoring the Bodhi Hot Yoga over the following 12 months, with a special focus on bifacial benefits from the reflecting wall surface, seasonal production fluctuation, and real-world savings versus the pre-installation power baseline. That data will be released and shared with the industry.
Vertical bifacial solar is not a substitute for rooftop or ground-mounted installations. But it is a realistic solution for commercial buildings in metropolitan areas.
