Duke Energy recently brought online a series of 50MW/94MWh battery storage projects in Florida, which vary in size and duration, with the last project being a 2.475MW/18MWh system due later this year Put into operation, using lithium-ion batteries as energy storage units.
Duke Energy explained that the system was used in a hurricane emergency shelter, so the batteries were made larger and lasted longer. When asked if other battery technologies had been considered when designing the project, and whether lithium-ion batteries would still be an option if redesigned today, Duke Energy said: “No other technology has been cost-effective when the project was designed. More competitive than Li-ion batteries, Duke Energy will continue to test new technologies and will pilot new chemistries in the future, however, if the project were to be redesigned today, Li-ion batteries would be less effective due to cost, performance characteristics and proven reliability Still the technology of choice.
It is worth noting that Duke Energy's above response is a strong point in the discussion about whether lithium batteries are suitable for long-term energy storage compared to flow batteries, but at the same time many long-term energy storage companies believe that the 8-hour duration does not count at all. Not for long.
According to system integrator Wärtsilä, the cost of lithium-ion battery energy storage projects has increased by 25% year-on-year, mainly driven by the cost of cells, as the price of lithium carbonate has soared by 1,000%.
Additionally, flow battery companies claim their solutions will be cheaper in the long run, although lithium-ion batteries continue to be used in many 6-hour and 8-hour projects, including a 50MW/400MWh system in California in March.
