The final step in capturing and storing carbon dioxide (CO₂) emissions is geological storage, where CO₂ is injected deep underground into carefully chosen locations. These locations could be natural formations like saline aquifers (underground reservoirs filled with salty water) or empty oil and gas fields.

This work, part of the AURORA project, focuses on finding the best underground storage sites for CO₂ emissions in the Mediterranean region. Scientists used well-established methods, similar to those adopted in countries like Norway and the UK, to carefully evaluate and select suitable sites. The results were compared to previous studies of the same areas to ensure accuracy.

Why the Adriatic Sea is a Focus

One key target area for CO₂ storage is the Adriatic Sea, which stretches from northern Italy (near Venice) to southern Italy (the Gulf of Taranto). This region has:

  • Proven geological formations that can trap CO₂ securely. These are the same formations where natural gas and oil have been extracted since the 1950s.
  • Deep saline aquifers and empty gas fields that are ideal for CO₂ storage.
  • Existing infrastructure like pipelines and facilities for gas management, which could be reused for transporting and storing CO₂.
  • Industrial centers nearby, which are sources of CO₂ emissions that need to be captured.

The Adriatic Sea is geologically significant because it was shaped by the movement of tectonic plates over millions of years. This movement created underground “traps” where gas, oil, or CO₂ can be stored safely. Similar storage opportunities also exist in neighboring regions like Croatia.

Other Regions of Interest

Beyond the Adriatic Sea, southeastern Europe has other promising locations for CO₂ storage, including:

  • The Balkan region (e.g., Greece, Croatia, and Romania).
  • Specific areas like the Mesohellenic basin in Greece, which contains large deep aquifers and empty oil fields with an estimated CO₂ storage capacity of up to 700 gigatons (a gigaton is one billion tons).

How Sites Were Evaluated

To identify the best storage sites, researchers used a two-part approach:

  1. Geological Assessment: They evaluated the underground formations to see if they are suitable for storing CO₂ securely and for a long time.
  2. Technical and Economic Evaluation: They assessed whether the site could realistically be developed, considering costs, infrastructure, and commercial readiness.

The methods used align with those in other European projects. This ensures the results are consistent and comparable across countries, helping standardize CO₂ storage site selection across Europe.

The AURORA project is helping identify and evaluate the best underground storage sites for CO₂ emissions in the Mediterranean. The Adriatic Sea stands out because of its geological suitability, existing infrastructure, and proximity to major industries. By standardizing methods for site selection, this research will help Europe move closer to achieving large-scale, safe CO₂ storage—an essential step in tackling climate change.