Geothermal Energy: Developing a Synergic Integration in Oil&Gas Fields Looking Forward to a Decarbonized Era
Claudio ALIMONTI, Davide SCROCCA, Elena SOLDO
[La Sapienza, University of Rome, Italy]
One of the main challenges of the future is the decarbonisation of the energy sector. Finding alternative energy sources to hydrocarbons, optimizing the energy production, integrating different energy sources, reducing waste heat and the environmental impacts are some of the current objectives of R&D departments of many companies. Since ’90, American and Chinese oil companies have studied the possibility of co-producing geothermal energy from oil and gas wells. In fact, the oil and gas production in its mature stage is often associated to a large amount of brines or formation waters which must be treated continuously and could not be released to the environment. Increasing the maturity of assets, the water production increases, so when the hydrocarbons wells are going to be depleted, they can be converted into geothermal wells. Regarding the use of geothermal energy, two main scenarios are available: the direct use of thermal power or the electrical power generation. The selection of the final use and the potential of geothermal production depends on the temperature, pressure and flow rate of water, which are function of local geothermal gradient, well depth, and poro-perm properties of the reservoir rocks. The oil and gas fields in the Italian territory are distributed in thrust belt, foredeep basin, and foreland geological settings. Hydrocarbon occurrences are related to at least five major petroleum systems which are associated to both carbonate and siliciclastic reservoir rocks ranging in age from Triassic to Paleogene and from Oligocene to Pleistocene, respectively. At the end of 2017, the total number of productive wells on the Italian territory was 1594, 881 wells are onshore and 771 are offshore. The possibility of a synergic integration of geothermal energy in these oil&gas fields represents a chance for Italy to increase the share of renewable energy production and to reduce the waste heat. Furthermore, the conversion of hydrocarbons fields into geothermal ones may be an opportunity to create a positive social response in the area where the oil and gas wells are located. The use of existing wells is a benefit for the oil companies, which avoid the cost of mining closure of the wells and for the geothermal companies, which avoid the cost of drilling new wells. The paper presents a preliminary investigation on some oil and gas wells located on Italian territory based on the available information provided by the Ministry of Economic Development. Taking into account the activities or land use of the territory, a conversion strategy for the producing wells has been proposed and evaluated with the SWOT analysis. The target is both to produce a vision of the potential benefits of the synergetic integration of geothermal energy in the Italian oil and gas fields and to propose an approach based on SWOT analysis in order to investigate the future life of the hydrocarbons wells in Italy.
|        Topic: Heat from Oil/Gas/Coal Fields||Paper Number: 41015|