Long duration energy storage has yet to make a significant dent in the global energy profile. To date, the only widespread form of storage technology that can last longer than a few hours is the century-old “water battery,” in the form of hydropower reservoirs and their cousins, pumped hydro reservoirs.
On the plus side, hydropower dams and pumped storage systems already sport transmission infrastructure. Developers are eyeballing them for additional green power by adding floating solar arrays. However, hydropower facilities are site-specific, they disrupt habitats, and they are increasingly vulnerable to climate impacts.
BNEF Pioneers is in its 10th year of identifying “the most impactful and original technology innovations for advancing the low-carbon economy,” and Energy Dome is the first company to represent Italy in the competitive program. The winning technology is a closed-loop CO2 system that hits the magic 4-hour ceiling for short term energy storage, and then charges past it for up to 24 hours.
As for cost, that’s the sticky wicket — or not, as the case may be. Lithium-ion battery arrays are currently the system of choice for utility scale energy storage. The US Department of Energy’s National Renewable Energy Laboratory has been tracking a downward trend in the cost of Li-ion arrays, based on a typical duration of 4 hours. Energy Dome estimates it can beat Li-ion on costs by a mile, delivering up to 6 times that duration at half the cost.
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Instant Long Duration Energy Storage: Just Add Carbon Dioxide#
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Carbon dioxide gets a workout in this new long duration energy storage system that can deliver wind or solar power 24/7.
