In order for intermittent renewables like solar power and wind to be the reliable around-the-clock energy sources needed to move away from fossil fuel energy and mitigate the climate crisis, they need long-duration energy storage to store all the power they produce.
However, as the most recent report from the International Energy Agency reports, more efforts are needed to achieve grid-scale storage demanded by the energy transition.
In the IEA’s ideal Net Zero Scenario, installed grid-scale battery storage capacity needs to expand 35-fold between 2022 and 2030 to nearly 970 gigawatts.
A big challenge to this scaling is the fact that most of these batteries are lithium-ion batteries. While the cost of lithium-ion has fallen dramatically in recent years due to the electric vehicle revolution, this has increased competition for lithium, leaving innovators to wonder what other types of batteries they can make, especially as the cost of lithium and other key minerals like copper rise again.
Nascent alternatives include technologies that use compressed air and gravity to store energy. Nevertheless, they play a comparatively small role in current power systems. Italian startup Energy Dome is out to change that with a recently closed $60 million Series B financing round.
However, instead of air, the startup is going an unconventional route and using planet-warming carbon dioxide.
According to Energy Dome, here’s the issue with the air and gravity situation, technically known as compressed air energy storage or CAES: Air has a low energy density under pressure, so it’s not the best vessel in the world for energy storage.
In order to combat this, some super smart people developed liquified air energy storage, or LAES, which gives the air a higher energy density. However, there’s another issue: LAES requires colder-than-imaginable temperatures, making it costly and complex, limiting the role it can play in the energy transition. According to the startup, CO2 has about 10-30 times the energy density potential of air. So, Energy Dome turned to it as a vessel.
With its invention of a CO2 battery, the company, which is a relative newcomer to the energy storage game, says it makes long-duration energy storage viable globally today.
This is how it works:
Energy Dome manipulates the CO2 between its gaseous and liquid phases. Whenever energy is needed, the CO2 warms up, evaporates, and expands, turning a turbine and generating electricity.
By now you must be thinking, that this releases extra emissions. Well, according to Energy Dome, this process emits no CO2 emissions into the atmosphere. Additionally, it completely takes highly sought-after minerals like lithium and copper out of the equation.
The team behind Energy Dome, which was founded in 2020, comes from a range of clean energy backgrounds from geothermal engineers to biomass powerplant technologists. But according to its mission statement, they all have one thing in common: “To fight climate change with new technology capable of drastically reducing greenhouse gas emissions into the atmosphere.”
As Canary Media reports, since 2019, the company has been able to move swiftly by repurposing existing materials and machinery to build novel grid storage plants, rather than inventing new materials or electrochemical processes. This pragmatic movement is what allowed the company to build a megawatt-scale project last year.
“Our technology can play a key role in enabling humanity to address the urgency of climate change without waiting until 2030,” founder and CEO Claudio Spadacini said in a statement.
The round was co-led by Eni Next, the corporate venture capital arm of Italian oil major Eni, and Neva SGR, the venture capital arm of banking group, Intesa Sanpaolo.
A slew of other investors participated in the first half of the round; the second part saw new participation from Innovation Development Oman Investments, the venture capital arm of Oman Investment Authority, the sovereign wealth fund of the Sultanate of Oman, and the venture fund of Royal Vopak, which describes itself as “the world’s leading tank storage company.”
According to Energy Dome, the funding will help the company achieve its global ambitions and reach “full commercial scale.” Already they have plans to work with utilities, independent power producers, and corporations across five continents. By the end of 2024, the company plans to have a 20-megawatt/200-megawatt-hour facility CO2 Battery project currently under development ready to go.
If successful the project would be a milestone for next-generation energy storage, because it would provide 20 megawatts for up to 10 hours straight compared to the average four hours of storage lithium-ion grid-scale batteries provide.