California is taking a small step toward its long-term goal of achieving 100% clean electricity by 2045 with a large investment in a hybrid energy storage system. Earlier this month, the California Energy Commission (CEC) awarded a $31 million grant for microgrid development for the Viejas Band of the Kumeyaay Indians. It is one of the largest sums the CEC has given to a tribal government and the first prize awarded by the state’s new $140 million long-life energy storage program, according to a Nov. 3 announcement by the commission.
The funding will support the creation of a long-life storage system with the capacity to supply up to 10 hours of microgrid power on demand. The goal is for this to serve as backup energy for the Viejas community to use during power outages, with the potential bonus of the tribe being able to use this system instead of the statewide power grid when that source is under stress. John Christman, president of the Viejas band of Kumeyaay Indians, also stressed the importance of such a system that provides clean, renewable energy.
“As large-scale electricity consumers, we recognize our responsibility to lead by example in reducing our load on the electricity grid, and it is our sincere hope that the demonstrated financial and environmental merits of this project will serve as a repeatable model for others ,” Christman said in the CEC statement.
Indian Energy, a Native American-owned microgrid developer and systems integrator, will lead production of the hybrid energy system. The CEC said it will be “one of the first of its kind in the country,” using a grid of solar panels and two different types of long-life storage batteries to generate and capture clean energy. Indian Energy will supply approximately 30,000 solar panels to generate 15 megawatts of power, while Eos Energy Enterprises will contribute a 35 megawatt-hour (MWh) zinc-based battery and Invinity Energy Systems will contribute a 10 MWh vanadium redox flow battery that can reserve the energy before it needs to be used. Utility dive reports that the tribe will later provide another 15 MWh of storage capacity, creating a total 60 MWh system.
Part of what makes this system unique is the use of non-lithium-ion batteries, which have become the go-to power source for many of the devices we rely on in our daily lives, from vacuum cleaners to electric cars. However, their ubiquity means they are in high demand, and using them for large-scale archiving can be costly. Also, as explained by Larry Zulch, CEO of Invinity Energy Systems Popular sciencethey are known to be flammable and lose their effectiveness over time.
Zulch calls vanadium redox-flow batteries what his company is designing for this network as “the workhorse of batteries” because they don’t have the same fire hazards as lithium batteries and can last for more than two decades. However, they take up a lot more space – Zulch says their redox flow battery units are about the size of a shipping container – so they work better in situations where there’s a lot more space available, than something like a battery of a cell phone.
[Related: How the massive ‘flow battery’ coming to an Army facility in Colorado will work]
Here’s how this “workhorse” supplies power: The container-like unit contains six modules. Each module has two tanks filled with liquid electrolyte and two stacks of cells, which are the key components for creating and storing energy. Electrolytes are pumped into the stacks of electrochemical cells, passing through membranes that facilitate an ion exchange.
While other elements can be used in flow batteries, such as iron, Zulch says vanadium is particularly amenable to use as an electrolyte in this process since it can exist in four different oxidation states with four types of electric charges. This change of state is reversible, so electrical energy can be stored and returned, which allows redox flow batteries to last so long.
“Basically, vanadium-flow batteries don’t use up the vanadium because it changes various states back and forth,” Zulch said, noting that some maintenance is required for the battery’s mechanical components from time to time.
While Invinity recently installed another similar battery for the Soboba Fire Station in California, this project for the Viejas Band of Kumeyaay Indians network will be their largest vanadium flow battery and the largest battery of its kind. in North America. Utility dive says the hybrid system should be operational by next summer.