Prospects for the use of carbon dioxide in enhanced geothermal systems in Poland

Abstract

The combination of geothermal energy extraction from hot dry rocks and geological storage of carbon dioxide is a technology whose implementation would contribute to reducing the anthropogenic emission of this gas.The possibility of using carbon dioxide as a working fluid absorbing heat from hot rocks with low permeability, considered since the beginning of the 21st century, is currently in the testing phase.In Poland, which lies outside the areas of contemporary volcanism, five prospective regions for the production of energy from enhanced geothermal systems were determined. Artificial reservoirs can be located both in sedimentary rocks (North-Western and Central Poland) and in igneous and metamorphic rocks (Western, South-Western and Southern Poland).Large emitters of carbon dioxide (emissions above 0.1 Mt per year in the mentioned prospective regions for the production of energy from enhanced geothermal systems (EGS) were determined. In the case of the five areas considered, there are 52 emitters of carbon dioxide (71 installations). The total emissions from the installations in 2016 amounted to 119.55 Mt of carbon dioxide, including emissions from fuel combustion installations, accounting for 106.46 Mt. Smaller amounts of around 1.5–3.0 Mt of CO2 were emitted by metallurgical plants, coking plants, chemical plants and oil refineries. Gas emitted from certain technological processes (e.g. the production of ammonia or hydrogen) contains high concentrations of carbon dioxide and can be used for EGS without carbon capture from the gas stream, which significantly reduces the costs of the entire project.