What is the benefit of having battery storage on the grid?

Large scale battery storage systems like the Sierra Estrella facility benefit the local electrical grid by providing resiliency and flexibility from a non-emitting capacity resource. Moving toward 100% renewable energy in a region like Arizona’s with exceptional solar resources requires balancing resources like the Sierra Estrella facility that can quickly adapt to evolving grid conditions over time. 

How did you choose the project location for Sierra Estrella?

The Plus Power team considered a variety of siting criteria, including but not limited to land use designations, archaeological and cultural resources, topography, and proximity to critical utility infrastructure. The Sierra Estrella facility location met the optimal criteria across categories.  

What prompted Plus Power to propose Sierra Estrella?

The Sierra Estrella facility is ideally situated to provide energy, capacity, and grid services in a region with growing local energy demand and abundant but variable renewable energy resources. 

How long will the batteries last? What will happen to them after that? 

The Sierra Estrella facility will have a lifespan of at least 20 years. The original battery systems installed at the site are anticipated to operate for at least 15 years. As the original system naturally degrades, Sierra Estrella will be augmented with supplemental battery storage units in the future. At the end of the project’s operating life, the facility will remove the battery system and restore the land to pre-existing conditions. Because the battery components contain valuable minerals, the system will be shipped away for recycling and salvage value. 

Are there environmental, cultural, or archaeological features that could be disturbed on the Sierra Estrella project site? 

Plus Power built the Sierra Estrella facility on a disused portion of an operating dairy farm. Therefore, there are no environmental issues. The site has been previously disturbed for agricultural use, and there are no known cultural or archaeological features within its footprint. 

What considerations are being taken to ensure the safety of the project? 

Safety is paramount to Plus Power and the Sierra Estrella facility. Several measures are being taken to ensure reliable and safe operation of the system. From a technology perspective, the Sierra Estrella facility utilizes best-in-class lithium-ion cells based on battery chemistries similar to those used in cell phones, computers, and electric vehicles, although the battery and system will be held to the National Fire Protection Association 855 national standard and other related grid infrastructure codes and standards. In addition, the system utilizes a variety of thermal management systems as well as remote monitoring strategies in order to maintain system stability. The Avondale Fire Department was fully engaged in design discussions as part of the Conditional Use Permit application, and the Plus Power team has led significant collaboration and training with first responders in order to guarantee proper techniques are used in the unlikely event of an emergency. 

Will Sierra Estrella be able to withstand a natural disaster? 

The Sierra Estrella facility was designed per ASTM standards to ensure foundations and infrastructure are designed in accordance with local requirements. A retention basin is utilized on site to manage stormwater and drainage. 

Will the Sierra Estrella facility impact my views? 

The Sierra Estrella facility is ideally situated away from populated areas and the site is screened by a masonry wall. As such, the impact on local views is very limited.