Central Sardinia is not typically known for being a hub of innovation. With its arid and rural landscape, and road signs marked with bullet holes from locals practicing target shooting, the setting evokes a scene from a Clint Eastwood western. However, in Ottana, on the former site of a petrochemical plant, a new technology is emerging that could help combat climate change. The main component of this technology is carbon dioxide, the primary contributor to global warming.
Energy Dome, a startup based in Milan, operates an energy storage demonstration plant in Ottana to address the surplus of electricity during the day when locals are at the beach, leaving excess supply. Claudio Spadacini, the CEO of Energy Dome, explained, “In Sardinia during the day, everyone goes to the sea. They don’t use electricity, but there’s a lot of supply,” referring to the abundant sunlight on the Italian island.
Energy Dome utilizes a large balloon filled with carbon dioxide, known as the “dome,” as a type of battery. During the day, electricity from the local grid, including power generated from nearby solar panels, is used to compress the carbon dioxide into liquid form. At night, the liquid carbon dioxide is expanded back into gas, powering a turbine to generate electricity that is then sent back to the grid.
While solar and wind energy are rapidly growing renewable sources, they depend on nature’s unpredictable schedule for electricity production. Many experts believe that storing this energy until needed, for hours or even days, is crucial for transitioning away from fossil fuels. Jennifer M. Granholm, the U.S. energy secretary, emphasized the importance of advancing energy storage technologies in achieving a decarbonized power grid.
Various companies are exploring innovative methods to store renewable energy, such as liquefying carbon dioxide, rusting iron, or heating sand-filled towers to extreme temperatures. However, predicting the future energy storage needs after a significant energy transformation is challenging, and the effectiveness and profitability of these approaches remain uncertain.
Elaine Hart, a founding principal at Moment Energy Insights LLC, a clean-energy consultancy, highlighted the urgency of decarbonizing electricity on an accelerated timeline. She emphasized the need for technologies like long-duration energy storage and hydrogen on a large scale within the next 15 to 20 years, underscoring the critical phase of their development.
