Hydrogen (H2) energy is gaining popularity as an important component of future energy mix. Hydrogen possesses significant potential as a clean energy carrier, particularly in the decarbonization of various industries. It also offers an alternative to achieve energy independence from fossil fuel based energy sources, which will also have a positive impact on climate change.
H2 applications range from providing heat to buildings to serving as a reliable fuel for trains, buses, and heavy trucks. The industrial sector has already made remarkable strides in reducing costs and enhancing the efficiency of H2 infrastructure. Presently, natural gas and gasoline with substantial carbon emissions dominate heating and transportation, respectively. For a complete transition to hydrogen based economy there is a huge requirement for hydrogen production and storage.
The use of H2 is highly effective and can help the energy sector achieve zero carbon emissions and increase energy flexibility. Within Lithuania there has been a strong push to adopt EU Hydrogen strategy to meet the EU’s commitment to carbon neutrality by 2050. It has also lead to creation of Hydrogen platform under the Ministry of energy with aim of fostering an enviorment to promote development of H2 technologies in Lithuania.
Although H2 is a very efficient fuel it has many challenges associated with its use. H2 being a very light gas requires large storage volume, therefore, for the effective adoption of H2 based technologies in Lithuania, question of H2 storage has to be addressed. Underground gas storage has been routinely carried out in Europe and even in Lithuania methane is stored in summer in underground (Inčukalns UGS ) formation, in Latvia, for use in winter period. Depleted gas field, oil fields and saline aquifers offers possibility to store large volumes of gas and it’s possible to use these underground porous formations for storing large quantities of hydrogen. Thanks to Lithuanian geology such possibilities exist in Lithuania in both onshore and offshore settings. The depleted hydrocarbon reservoirs and deep saline aquifers in Lithuanian basin have been investigated for CO2 storage in the past, these reservoirs are equally good for storing hydrogen as well.
Subsurface reservoirs and aquifers can be considered as a cost-effective option for underground H2 storage, typically porous sandstone or other permeable rock layers. While underground hydrogen storage (UHS) sounds promising there are some technical challenges associated with it and there is a need to carry out a study with the aim of improving the understanding of the complex geochemical processes and hydrochemical changes within the subsurface layers due to Hydrogen storage and also to evaluate possible leakage of H2 and its impact on shallow aquifers.
First, there is a need to calculate at high level total underground hydrogen storage potential in Lithuanian reservoirs basin. Underground hydrogen storage may be affected by geochemical and microbial reactions, residual hydrogen trapping, leakage, and water production during hydrogen extraction, which can lower the hydrogen storage efficiency over time. The injected hydrogen can originate geochemical and microbial reactions leading to a new chemical equilibrium between rock minerals, dissolved gasses, pore water, and rock matrix. Such in-situ reactions could lead to precipitation or dissolution of rock minerals. Further, bacterial action can lead to the formation of biofilms resulting in pore-clogging. Precipitation/dissolution and pore-clogging can change the porosity and permeability of underground hydrogen storage reservoirs over time, which over time may lead to large volume of hydrogen being trapped and unrecoverable.
Additionally, some challenges associated with uncertainties in the flow properties, storage integrity, and their impact on shallow aquifers and geological formations if leaks happen during underground stored H2 also need to be addressed. Geophysical data sets along with micro-scale core sample images, and geochemical and reservoir simulations will be used to address the concerns and we will try to develop effective pathways to determine the leakage impacts.
Aim of this study is to address the above-mentioned issues and challenges related to the underground storage of hydrogen through data collection, data analysis, data re-evaluation, modeling, and simulation. This study will aid the development of a plan of action for environmentally friendly hydrogen energy storage infrastructure in Lithuania.
Project funding:
Research Council of Lithuania (RCL), Projects of Postdoctoral fellowships funded by the state budget of the Republic of Lithuania
Project results:
work in progress
Period of project implementation: 2024-04-02 - 2026-04-01
Project coordinator: Kaunas University of Technology