| Title | Repurposing hydrocarbon Wells in a circular economy perspective: the integration of geothermal energy in Biogas plants |
|---|---|
| Authors | Claudio Alimonti, Davide Scrocca |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | The EU’s ambitious decarbonisation goals and the need for energy security require transitioning from fossil fuel-based systems. This phase-out of hydrocarbon production will also likely lead to the closure of currently producing wells. Therefore, before making this irreversible decision involving high costs, it is advisable to evaluate all the possible solutions for the alternative use of existing wells, such as their reuse for geothermal applications. A geothermal assessment for oil and gas fields in Italy identified 42 fields at depths between 2000 and 3000 m. Temperatures associated with these oil and gas wells are often low to medium, approximately 50-80 °C. Therefore, temperatures in this range can contribute to the energy supply of plants requiring thermal energy in a circular economy perspective. Biogas plants convert materials previously regarded as waste into renewable energy, nutrient-rich organic fertiliser, and novel materials. They require heat to keep the reactor at a constant temperature and to heat the incoming biomass. The wells in the Irminio fields (Sicily, Italy) were chosen for a case study. The current business is the production of oil and the use of co-produced gas in a cogeneration plant. This solution was adopted to integrate a cogenerator into the production process to make the most of the plants' tail gas. This case study evaluated the use of the organic fraction produced in the province of Ragusa (RG) municipalities. The proposed scheme has general applicability in all possible existing wells. |