Underground storage of renewable hydrogen in depleted gas fields and other geological stores
The main objectives of this topic are to research the feasibility of implementing large-scale storage of renewable hydrogen in depleted gas fields and other types of geological store, and to undertake a techno-economic assessment of how the underground storage of renewable hydrogen could facilitate achieving a zero-emissions energy system in EU by 2050.
Suitable geological stores should be identified and classified, together with information concerning nearby connecting infrastructure and wind/solar farms. The outstanding feasibility questions should be defined, and a research plan of laboratory and possibly field tests and literature surveys implemented to cover all questions concerning geological, microbiological, engineering and economic factors. The analysis should help clarify whether most of the hydrogen can be recovered, or if a significant percentage would be lost due to dissolution, diffusion, viscous fingering, chemical reactions or leakage.
Cyclability and longevity aspects of such stores should also be addressed. The geographical distribution across EU of all suitable types of geological store and their potential hydrogen capacities should be also identified.
A comprehensive techno-economic analysis of the considered approach should be undertaken, building on the findings of the HyUnder project [57], to examine the potential for its widespread implementation across the period 2025-2050. This should include (onshore and offshore) mapping of the proximity of suitable underground stores with existing and future wind/solar farms, modelling the production of renewable hydrogen, associated gas compression and hydrogen pipeline networks to transfer hydrogen to/from the stores, and identifying the profiles and amounts of renewable energy that can be buffered by such storage facilities to meet time-varying energy demands across all end use sectors. The developed model should identify how to match renewable supply with energy demand at all times by appropriately sizing and operating the technologies involved in producing, storing, distributing and using renewable hydrogen. Future scenarios should be formulated or existing scenarios/roadmaps should be reviewed for the EU to establish the considered approach at a prodigious scale by 2050.
In addition, the techno-economic feasibility of implementing hydrogen storage in preferred locations should be assessed to a level sufficient to support a decision whether or not to proceed to field pilot demonstration. This will provide substantial insights into the suitability for implementing such storage across EU and enable the development of positive business cases for adoption.
The project consortium should involve geologists to undertake expert analyses of underground storage opportunities for a wide range of sites across EU, both offshore and onshore.
TRL at start of the project: 3 and TRL at the end of the project: 5.
Any safety-related event that may occur during execution of the project shall be reported to the European Commission's Joint Research Centre (JRC) dedicated mailbox JRC-PTT-H2SAFETY@ec.europa.eu , which manages the European hydrogen safety reference database, HIAD and the Hydrogen Event and Lessons LEarNed database, HELLEN.
“CertifHy Green H2“ guarantees of origin should be used through the CertifHy platform [58] to ensure that the hydrogen produced and injected underground is of renewable nature.
The maximum FCH 2 JU contribution that may be requested is EUR 2.5 million. This is an eligibility criterion – proposals requesting FCH 2 JU contribution above this amount will not be evaluated.
Expected duration: 2 years
[57] https://www.fch.europa.eu/page/cross-cutting-issues-0#HyUnder
The increasing contribution of variable renewable energy (VRE) in the electricity grid is creating a substantial temporal mismatch between supply and demand. To balance this daily to seasonal mismatch it is necessary to have a large facility for storing and withdrawing VRE. Underground storage of gas molecules is cost efficient, environmentally friendly, and suitable for storing large amounts (e.g. more than 200 GWh per salt cavern or over 1,000 GWh in a gas field). The combination of VRE, electrolysers and geological storage can therefore provide a means for capturing and holding renewable energy at an unprecedented scale for satisfying time-varying energy demands. When moving towards a fully renewable system, very large volumes of hydrogen storage will be needed and the rates of energy transfer in/out the store will vary substantially across the day/year, with associated variations in pressure level. It is therefore important to understand whether EU can find a suitable storage option using its depleted gas or oil fields and other geological stores in a time-varying cyclic manner to buffer the future energy system with renewable energy.
Although pure hydrogen storage in salt caverns is practiced in some locations, hydrogen storage in depleted gas or oil fields has not been done anywhere in the world – only few attempts to inject hydrogen up to a certain percentage. Lab and field trials have shown that hydrogen can yield geochemical and microbiological reactions in the subsurface. Also, hydrogen has different mobility, dissolution and diffusion characteristics, when compared with natural gas. Some preliminary studies are indeed promising regarding the possibility of using the depleted fields for hydrogen storage, but further research and experimentation is required.
The project should:
- Establish the geochemical, mineralogical and microbiological reactions occurring in geological stores in the presence of hydrogen;
- Improve understanding of the scalability of the demonstrated approach if replicated across Europe and the associated requirement for hydrogen infrastructure and renewable power sources;
- Provide a detailed techno-economic assessment of future scenarios for the EU to achieve widespread deployment of underground renewable hydrogen storage by 2050;
- Provide insights concerning the value chain and which parts need further study or development to establish positive business cases (covering technology development/selection, operation, location, system integration and other aspects).
The conditions related to this topic are provided in the chapter 3.3 of the FCH2 JU 2020 Annual Work Plan and in the General Annexes to the Horizon 2020 Work Programme 2018– 2020 which apply mutatis mutandis.