Carbon Dioxide Transforms into a Super Battery: Google Bets Big, While China, the U.S., and India Compete

At this critical juncture of energy transition, long-duration energy storage technologies—typically defined as those capable of discharging for more than four hours—are emerging as an industry imperative. Although mainstream lithium-ion batteries respond rapidly, they generally discharge only for 4 to 8 hours, making them ill-suited to address prolonged power deficits. Meanwhile, the stability of photovoltaic and wind power also poses challenges: how can grid reliability be ensured when the sun sets or winds subside? While pumped hydro storage systems are relatively reliable, they require specific topography and entail lengthy construction timelines—often up to a decade. Against this backdrop, Italian startup Energy Dome has proposed an entirely novel energy storage solution—the carbon dioxide battery. Its core principle leverages the phase change between gaseous and liquid CO₂ to store and release energy. In July 2025, Energy Dome’s first commercial facility—located in Ottana, Sardinia, Italy—officially commenced operations, with a capacity of 20 MW / 200 MWh and a continuous discharge duration of 10 hours. This marks a pivotal step from demonstration to commercialization for CO₂-based energy storage. Faced with this emerging technology, tech giant Google announced in the same month a commercial partnership with Energy Dome, along with an investment. Google plans to deploy such storage facilities near its data centers across Europe, the United States, and the Asia-Pacific region to support its goal of achieving 24/7 carbon-free energy operation by 2030. Energy Dome’s storage system resembles a massive inflatable dome in appearance, yet its core consists of a sophisticated thermodynamic cycle apparatus. It is a fully closed-loop system emitting no gases into the atmosphere. When renewable energy supply on the grid exceeds demand, the system activates compressors to compress ambient-pressure CO₂ inside the dome into liquid form, storing it in carbon-steel pressure vessels. The heat generated during compression is not wasted; instead, it is captured and stored in thermal energy storage systems using steel or quartzite media. When grid electricity is needed, the liquid CO₂ is released and heated using the stored thermal energy, evaporating into high-pressure gas that drives a turbine to generate electricity. After completing its task, the CO₂ flows back into the dome, ready for the next cycle. The system offers clear economic advantages. Calculations indicate its levelized cost of storage (LCOS) is 30% lower than that of lithium-ion batteries, and its service life is three times longer. Moreover, its raw materials—steel, water, and CO₂—are common industrial commodities, eliminating dependence on scarce minerals like lithium, cobalt, and nickel, thereby ensuring stable supply chains. Unlike electrochemical batteries, it does not suffer performance degradation over repeated charge-discharge cycles during long-term operation. Furthermore, deployment speed is exceptionally fast. Claudio Spadacini, Founder and CEO of Energy Dome, states that the system requires only about five hectares of flat land and can be built in under two years—enabling rapid replication whether in U.S. industrial parks or the plains of India. This standardization is unmatched by pumped hydro or compressed-air energy storage. Additionally, the system preserves a unique advantage of conventional power plants—grid inertia.

To Power Data Centers, Tech Giants Are Pinning Their Hopes on Carbon Dioxide?

Global Zero Carbon The 'New Youth' of Carbon Neutrality → This is Global Zero Carbon’s 2028th original article Today, all grand narratives surrounding AI ultimately hinge upon their underlying energy infrastructure. The AI “computing power race” is, in essence, a “power race”—a consensus now widely shared across the industry. As electricity demand surges, the importance of energy storage likewise intensifies. Storage, as the sole realistic option for bridging power gaps, is increasingly viewed as a new “entry barrier” in AI industry competition. In response to the intermittency and volatility of renewable energy, power systems are growing ever more reliant on long-duration energy storage (LDES) technologies—capable of discharging for more than four hours, even spanning weeks or seasons. Against this backdrop, tech giants have turned their attention to a greenhouse gas typically regarded with disdain: carbon dioxide. CO₂ can store electricity derived from renewable sources when transitioning from gas to liquid—and conversely, release energy to generate electricity when reverting from liquid back to gas. This property positions CO₂ as a potential climate crisis solution, helping mitigate the intermittency and instability inherent in renewable power generation. On June 15 local time, Italian long-duration energy storage developer Energy Dome entered into a partnership with Arizona-based utility Salt River Project (SRP) to develop a 19-MW, 10-hour CO₂ battery energy storage project at SRP’s Colorado Generating Station site in eastern Arizona. The project will be developed under a 20-year tolling agreement: “Energy Dome will own and operate the facility, while SRP will dispatch its power output,” SRP stated in a press release. The project is scheduled to enter operation in 2029, with stored energy sufficient to power approximately 4,275 households for 10 hours. This project is also part of an innovative collaboration between Google and SRP, aimed at accelerating the deployment of non-lithium-ion long-duration energy storage (LDES) technologies to enhance energy reliability, affordability, and sustainability. Google will contribute partial funding through a cost-sharing agreement with SRP. Claudio Spadacini, Founder and CEO of Energy Dome, remarked: “At a time when AI development and surging demand are reshaping America’s energy landscape, CO₂ batteries offer scalable, dispatchable capacity that helps strengthen U.S. energy dominance. This solution can be built rapidly, manufactured domestically, and supported by our expanding U.S.-based service capabilities—enabling SRP to bolster energy security using locally produced power from Arizona.” Caption: Rendering of Energy Dome’s CO₂ energy storage system This is not the first time Energy Dome’s CO₂ battery has been selected this year as an energy storage solution for AI-powered data centers. In early April, U.S. digital infrastructure firm New Era Energy & Digital (NUAI) signed a memorandum of understanding (MOU) with Energy Dome to deploy its CO₂ storage technology at a data center project in Odessa, Texas—targeting service for a 1-GW, AI-optimized data center.

Italy's Energy Dome in Advanced Talks for Major Funding, Keeps IPO Option Open

13 hours ago

Italian startup Energy Dome is advancing talks to raise hundreds of millions of euros for its CO2-based energy storage technology, backed by investors including Eni Next and Breakthrough Energy Catalyst. The firm plans to expand manufacturing capacity in Italy while maintaining an IPO option contingent on market conditions.

reuters

2026-10-08

Italy's Energy Dome in Advanced Talks for Major Funding, Keeps IPO Option Open

Italy's Energy Dome in Advanced Talks for Major Funding, Keeps IPO Option Open

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