Even with a relatively short duration of four hours, Li-ion batteries are anticipated by the US Department of Energy to replace gas “peaker” plants, which are typically used only to provide additional electricity during periods of peak demand. Replacing continuously operating baseload gas power plants is a more advanced task suited for longer-duration systems. In this field, pumped hydropower continues to dominate. Although it is a proven and mature technology, it is limited by geography, water availability, and environmental and cultural concerns. In the US, pumped hydropower still accounts for about 95% of all long-duration energy storage capacity.
New, more flexible, and location-agnostic technologies are emerging for long-duration energy storage, such as compressed air and thermal storage systems. Flow batteries are also part of this mix. They operate on the principle that two specialised fluids can generate electricity when in motion, flowing next to each other and separated by a thin membrane that enables ions to pass through.
In 2014, CleanTechnica noted some emerging flow battery technologies. We observed that flow batteries score points for longevity as they do not degrade over time like lithium-ion batteries, making them ideal for intermittent energy storage. They can sit idle for long periods without losing their charge and can be activated almost instantly when needed. Until recently, typical flow batteries were bulky, but more compact systems have been emerging along with lower costs.
Vanadium, an abundant metal commonly used in the steel and titanium industries, is among the substances favoured for flow batteries due to its abundance, non-toxicity, and relatively low cost. It can be mined or recovered from industrial waste and is found in various foods, including mushrooms and black pepper. Vanadium can exist in two ionic states, allowing it to be used in both fluids in flow batteries. However, developing a cost-effective energy storage system using vanadium is not simple, partly due to heat management issues and high manufacturing costs.
In 2020, the US Department of Energy launched the $20 million Energy Storage Grand Challenge to support innovations that reduce the cost of manufacturing flow batteries. The Department explained that manufacturing flow battery systems of sufficient size is necessary to meet the expected demand for stationary grid storage. The current sizes of flow battery cells, which demonstrate the most advanced materials and components, are significantly smaller than those needed for commercial use.
Ferro-Alloy Resources Ltd (LON:FAR) is developing the giant Balasausqandiq vanadium deposit in Kyzylordinskaya oblast of southern Kazakhstan. The ore at this deposit is unlike that of nearly all other primary vanadium deposits and is capable of being treated by a much lower cost process.
