Israeli company BaroMar is set to revolutionize long-term energy storage by using compressed air in low-cost underwater tanks. As renewable energy usage rises, so does the need for effective energy storage systems. While lithium-based batteries are ideal for short-term storage, long-term solutions are required for sustained energy needs. BaroMar’s new approach promises an innovative and cost-effective way to store energy for extended periods. Here’s how it works.
How Does BaroMar’s Compressed Air Energy Storage System Work?
BaroMar’s compressed air energy storage (CAES) system uses surplus electricity to power compressors that pump high-pressure air into underwater tanks. When electricity is needed, the compressed air is released through a turbine, generating power. The company claims that this system is not only cost-effective but can also store energy for weekly, monthly, and even seasonal durations.
Using Water Pressure to Reduce Tank Costs
BaroMar’s facilities are planned to be located near coastal areas with deep water access. Instead of using costly high-pressure tanks, the company leverages water pressure to maintain the compressed air. The system employs concrete and steel tanks submerged at depths of 200-700 meters, stabilized with rock and steel cages. The tanks are filled with seawater, and the surrounding water’s hydrostatic pressure balances the internal air pressure, reducing the need for heavily reinforced and expensive tanks.
Energy Recovery and Performance
To recover stored energy, the system releases the compressed air through a thermal recovery system and into a turbo expander that drives a generator. This process forces water out of the tanks and then refills them as the pressure equalizes. BaroMar’s pilot project in Southern Cyprus aims for a round-trip efficiency of about 70%, comparable to the world’s largest CAES plant in China, which boasts a capacity of 100 MW and 400 MWh. The Southern Cyprus system will have a 4 MWh capacity.
Competitive Advantages and Challenges
BaroMar asserts that its system, with long-lasting and low-cost tanks, will outperform its competitors in long-term energy storage. The company’s Levelized Cost of Storage (LCoS) is approximately $100 per MWh, significantly lower than the $131 per MWh of other long-term energy storage systems. Although designed to operate underwater for 20 years, the system faces challenges, including geophysical and geotechnical studies, site permits, and logistical complexities for deep-sea installation.
Despite these challenges, BaroMar’s underwater CAES system presents an innovative and scalable alternative for cost-effective energy storage, promising a significant breakthrough in the field.
