Grand Canyon West Microgrid Project
Peach Springs, Ariz. | 884.5 kW solar + 2.14 MWh storage
The 2023 Solar Builder Microgrid Project of the Year Award winner, as voted on by our readers, is the Grand Canyon West Solar + Storage system in Peach Springs, Ariz.
This 884.5 kW fixed-tilt ground-mounted solar + 770 kW / 2.14 MWh battery energy storage system (BESS) serves the Hualapai Tribe and provides electricity for Grand Canyon West operations, including the popular Grand Canyon Skywalk and other local attractions. The system also includes a microgrid controller and medium voltage grid stability equipment.
Completed in June 2023, the project replaced a diesel-generation microgrid. The BESS serves as the grid-forming source and significantly reduces operational costs while increasing reliability of the microgrid. The solar and battery are expected to provide 50% of the needed energy for the entire site.
Developer/EPC/Installer: SOLON Corp.
Inverters: CPS America
Mounting/Racking: APA Solar Racking
Keys to connection
Planning for the future was a crucial component in the development of this project. The local utility is expected to provide power to the area in the future, so it was essential that the microgrid be optimally designed for today’s needs, while planning for a future grid connection, says Cary Broschat, VP of engineering and pre-construction for SOLON Corp., which served as the developer, EPC and installer on the project.
“The tribe has received a grant to bring in a new utility line to their area, which is great for them,” Broschat says. “That process is expected to take several years to develop and install that line. Throughout the course of the project, that’s something we had to consider to make this system grid-connection ready.”
The battery system had to be compatible with the future grid connection and work seamlessly with that source, Broschat explains. In the future, that built-in compatibility will allow the tribe to take the generators completely offline, and potentially only use them as a backup system.
“It will really allow them to replace that generator usage with utility grid usage,” Broschat says. “They can still rely on their PV power and their battery power to support the bulk of their loads when those sources are available, but really just have a very firm, cleaner and cheaper source of power for them in the future once they do establish that grid connection.”
The most extensive challenge with this project was developing a solution that interfaced with their existing generators and microgrid and establishing a complete microgrid sequence of operations to ensure grid stability.
Upgrading an expensive, fossil fuel-based grid
There are about 2,000 members of the Hualapai Tribe living in Peach Springs, Ariz. Their electric microgrid is powered by three diesel generators that, over time, became expensive to operate, says Luke Alm, VP of business development at SOLON. The tribe worked with the U.S. Department of Energy and SOLON to develop the Grand Canyon West microgrid project that would reduce their operational costs and overall environmental impact.
“We ran literally thousands of different iterations of different equipment, solar, and battery storage to determine the optimal system to put in place for the tribe,” Alm says. “We arrived at 885 kW of solar PV and 2.14 MWh of energy storage to interface with only one of their existing three generators. Depending on the year, the goal is to produce about 40-50% of the tribe’s electricity needs to significantly reduce their electricity costs and use of fossil fuels.”
The project was finalized when the DOE offered a grant to pay for a portion of the project, Alm adds.
The project site posed several challenges for the project team, Broschat says. SOLON took measures to preserve cultural resources, while also juggling the logistics of working in a remote location.
“There was obviously a screening for cultural resources that happened by the tribe before the site was even selected to make sure there were no conflicts there,” Broschat says. “We ended up installing a screen fence around the solar and battery system in order to limit visibility of the system and not detract from the natural beauty of the area.”
The project team had to coordinate the use of a crane during construction when they were setting the battery system, and during other operations, due to the proximity of a heliport adjacent to the project site.
“The remote nature of the site definitely added another layer of complexity to the project,” Broschat says. The logistical challenges related to working in a remote location involved materials and equipment delivery, as well as various on-site services.
Additionally, the project team had to work around the active facility operations at the Grand Canyon, such as concessions and the Skywalk.
“We had to make sure that throughout construction, commissioning and testing processes that we didn’t impact those operations in a negative way,” Broschat says.
The geotechnical conditions of the site also presented challenges during construction.
“There is a heavy amount of bedrock in the area at pretty shallow depths, in some cases exposed bedrock on the site,” Broschat explains. “We originally contemplated a ballasted foundation for the solar array. We eventually changed that to using ground screws.”
Financing the project
The Hualapai Tribe received a large grant from the DOE that funded more than 60% of the project, Alm says, estimating that the new microgrid will save the tribe about $0.40 per kWh compared to the old diesel generators.
“The savings will be significant,” Alm says. “The tribe should be saving between $500,000 and $750,000 per year right away, depending on how much cost you allocate for generator maintenance and repairs. Due to the generator cost savings and the DOE grant, the project should pay for itself within 1-2 years.”