Canadian start-up Zinc8´s hybrid flow battery can make wind or solar farms baseload and could transform the utility-scale energy-storage market, writes Leigh Collins
A new type of battery is coming onto the market that can store multiple days’ worth of energy, that doesn’t degrade, can’t possibly explode and is up to five times cheaper than lithium-ion, claimed its developer as it prepares to pilot the technology in New York state.
The zinc-air hybrid flow battery developed by Canadian company Zinc8 has the potential to disrupt the entire energy-storage market — making wind and solar farms baseload and even replacing the need for transmission grid upgrades in many places.
“For large-scale energy storage, lithium-ion can’t touch us on cost,” says chief executive Ron McDonald, a former Canadian member of Parliament who now oversees a company that has received $100m of funding.
Zinc-air can beat lithium-ion batteries on price because the latter can generally only hold about four hours’ worth of energy at any one time, so an eight-hour storage system would require two batteries. By contrast, the storage capacity of the Zinc8 system can just be made bigger by increasing the size of the storage tank and the volume of the electrolyte it contains.
The capital cost of an eight-hour Zinc8 storage is about $250/kWh, falling to $100/kWh for a 32-hour system and $60/kWh for 100 hours. By contrast, lithium-ion projects cost about $300/kWh for any duration over eight hours.
“Our market is eight hours [of storage] and above,” McDonald tells Recharge. “And the reason is that as you increase your storage capacity — the overall cost of the system continues to go down very significantly.”
In terms of levelized cost of storage (LCOS) — ie, the cost of storing each MWh of energy across a project’s lifetime, taking into account all capex and opex — zinc-air blows lithium-ion away for storage capacities higher than eight hours. This is because the LCOS of lithium systems, for long-duration applications that require daily or multi-day full cycling, roughly doubles for every ten hours of storage capacity added, compared to every 70 hours or so for zinc-air.
This means that a 10-hour zinc-air storage system would have an LCOS of about $100/MWh, compared to $125/MWh for lithium-ion. But a 72-hour zinc-air system would have an LCOS of about $180/MWh, compared to more than $600/MWh for lithium.
The cost of the zinc-air battery is expected to fall significantly as manufacturing is stepped up.