Clean energy start-up Energy Dome has developed a large battery which uses CO2 instead of lithium to create and store electricity. Not only does this provide a solution for putting captured emissions to good use, the batteries are also cheaper to produce than standard batteries.
Energy Dome has been building and testing their first large-scale battery in Sardinia, Italy since 2020. In June this year they announced they have finished testing and the battery is ready for commercial use.
Whist the battery system is quite complex it has two main components; a giant gas chamber and a turbine which is all housed inside a giant dome. To charge the battery CO2 is compressed inside a chamber which creates liquified CO2, which is then stored and ready to produce power.
When the battery is in use, the CO2 is evaporated, which powers a turbine that generates electricity. CO2 is then returned back into the chamber ready to start the process again. This whole process is completed without creating any emissions.
Pioneers in zero emissions power
In April, Energy Dome won the Bloomberg New Energy Finance (BNEF) Pioneers 2022 Technology competition under the category “providing round-the-clock zero-emissions power”.
Energy Dome Founder and CEO Claudio Spadacini said:
“To be selected as a BNEF Pioneers 2022 winner is not only a huge honor, but also a strong validation of our technology and product, the CO2 Battery, which we are deploying at commercial scale”.
Whilst this battery isn’t going to replace other clean technologies such as wind and solar it is seen as a complementary technology. During months of the year where there is limited sun or wind, technologies such as Energy Domes’ CO2 battery have the potential to fill the gap in the clean energy market. With some countries rapidly moving to eliminate their reliance on coal there is a growing market for innovative clean energy solutions.
The future is looking bright
Energy Dome has signed multiple agreements to build CO2 batteries, including one for the Italian power company A2A, which is due to be completed by the end of 2023.
The Sustainable Impact Capital program which is funded by Barclays Bank and CDP Venture Capital announced on the 28th of June that they are awarding Energy Dome $11 million in funding to assist with expansion. The program funds early-stage companies accelerating the transition to a net-zero future.
“Energy Dome’s technology plays an important role in the transition to renewables, addressing the need for viable energy storage solutions. Their launch into the market is an exciting next step in Energy Dome’s journey, and we are delighted to continue our partnership as they scale up for the future.” said James Ferrier, Head of Sustainable Impact Capital at Barclays.
Where does the energy come from to liquefy the CO2 ?
Missing from this story is efficiency: For every kilowatt of energy released, how many watts were needed to store that energy, or what percentage of energy in comes out again? This looks like a solution that can be scaled up, and unlike chemical batteries probably has unlimited duty cycles, so that is good. But managing the heat of compression and evaporation of gas will probably lead to poor efficiency compared to other methods.
I need someone to explain to me how the physics works with this system. I was always taught that no machine efficiency is 100%. So, to compress the CO2 and liquefy it takes energy — more energy than we should get out of letting it expand to drive a turbine. If someone can clue me in, I’d appreciate it.