Central Sardinia just isn’t generally considered a hotbed of innovation: the world is barren and rural, with some road signs dotted with bullet holes made by locals practicing goal practice, and the scenery is harking back to a Clint Eastwood Western. But in Ottan, on the brownfields of former petrochemical plants, a recent technology is taking shape that would help the world slow climate change. The key element of this technology is as unlikely because the distant location: carbon dioxide, the leading explanation for global warming.
Energy Dome, a Milan-based start-up, is running an energy storage demonstration plant that helps address the mismatch within the local electricity market. “During the day in Sardinia, everyone goes to the seaside,” said Claudio Spadacini, CEO of Energy Dome. “They don’t use electricity, but there is plenty of it,” he added, referring to the abundant sunlight on the Italian island.
Energy Dome uses carbon dioxide stored in a huge balloon, called the “dome” in the corporate’s name, as a form of battery. During the day, electricity from the local grid, partly generated by nearby solar cell fields, is used to compress carbon dioxide into a liquid. At night, the liquid carbon dioxide is expanded back into a gas, which drives a turbine and produces electricity that’s fed back to the grid.
Solar and wind power are rapidly growing renewable sources, but electricity generation relies on nature’s intermittent schedule. Many researchers and policymakers argue that storing such energy until it is required, for hours and even days, is vital to shifting the economy away from fossil fuels. “Advances in energy storage technologies are critical to achieving a low-carbon energy grid,” said Jennifer M. Granholm, U.S. Secretary of Energy within the 2022 statementwhen her department announced it will commit greater than $300 million to long-term energy storage.
Companies are developing and marketing diverse and inventive ways to store renewable energy: liquefying carbon dioxide, derusting iron, heating towers full of sand to temperatures almost high enough to melt aluminum. However, predicting our future energy storage needs after a massive energy transition is a daunting prospect, and it’s unclear which, if any, of those approaches will prove effective and cost-effective.
“There is a really urgent need to decarbonize electricity much faster than we have considered in the past,” said Elaine Hart, founding father of Moment Energy Insights LLC, a clean energy consulting firm. “We don’t need technologies like long-term energy storage or hydrogen today, but we may need them on a large scale in the next 15 to 20 years, so we are at a critical moment for their development.”
