Hydrogen Storage In European Subsurface

Project Information

HyStorIES

Grant agreement ID: 101007176

DOI

10.3030/101007176

Project closed

EC signature date 5 December 2020

Start date 1 January 2021

End date 30 June 2023

Funded under

• SOCIETAL CHALLENGES - Secure, clean and efficient energy

Total cost

€ 2 499 911,75

EU contribution

€ 2 499 911,75

Coordinated by

GEOSTOCK SAS
France

Periodic Reporting for period 2 - HyStorIES (Hydrogen Storage In European Subsurface)

Reporting period: 2022-01-01 to 2023-06-30

Summary of the context and overall objectives of the project

Renewable hydrogen combined with large scale underground storage enables transportation of energy through time, balancing out the impacts of variable renewable energy production. While storing pure hydrogen in salt caverns has been practiced since the 70s in Europe, it has never been carried out anywhere in depleted fields or aquifers.

Technical developments are needed to validate these two solutions. As subsurface technical feasibility studies for a future hydrogen storage in depleted field or aquifer will be site-specific, as for other geology related activities, Hystories is providing developments applicable to a wide range of possible future sites: the addition of H2-storage relevant characteristics in reservoir databases at European scale; reservoir and geochemical modelling for cases representative of European subsurface, and tests of this representativeness by comparing it with results obtained with real storage sites models; and lastly an extensive sampling and microbiological lab experiment programme to cover a variety of possible conditions.

Complementarily, techno-economic feasibility studies are providing insights into underground hydrogen storage for decision makers in government and industry. Modelling of the European energy system will first define the demand for hydrogen storage. Environmental and Societal impact studies will be developed. For a given location and hydrogen storage demand, a high-level cost assessment for development of each of the competing geological storage options at that location will be estimated, and the sites will be ranked based on techno-economic criteria developed within the project. Finally, several case studies will enable consideration of the implementation of potential projects, notably by considering their economic interest.
This is providing substantial insight into the suitability for implementing such storage across EU and enable the proposition of an implementation plan.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Subsurface technical feasibility studies for a future hydrogen storage in depleted field or aquifer are site specific, as they are for natural gas and for other geological related activities. To provide the best possible insights to project developers of storage sites that are yet to be defined, different strategies have been applied for each of the technical challenges requiring development:
• Based on the experience in screening sites for developing new natural gas storages, scoring and screening criteria have been proposed to support the selection of porous media storage site candidates for pure hydrogen storage. 27 properties have been grouped into three categories: geological and reservoir engineering; geological context and surface environment. For each property, a criteria is proposed and its importance is estimated regarding local impacts, the storage capacity (in Nm3) and the storage performance (in Nm3/h). This is used to advance a database of geological storage opportunities at the European scale by addition of data of specific relevance to geological storage of hydrogen.
• To answer reservoir engineering questions such as effects of mixing, structural trapping for H2, a high mobility gas, a workflow has been set to use results of the above-mentioned database and build synthetic models based on available properties. Estimates of the storage capacity and deliverability are made at a European scale.
• To determine expected microbial activity and impacts, seven different brines and rocks (cores or cuttings) from gas storage sites are being used in a large experimental microbiological investigation. The outcome of this extensive sampling and lab experimental program and data gathering from a wide range of relevant geological conditions is a rare opportunity to propose results across a large variety of possible conditions.
• Determining what steel grade can be used for underground hydrogen storage is a question faced by technical developers of underground hydrogen storage today. Contrarily to hydrocarbons (not corrosive), hydrogen contact with steel creates risks of Hydrogen embrittlement. The project is investigating what material (steel grade) can be used for underground hydrogen storage under which conditions. To cover a diversity of reservoir conditions (temperature and pressure) and gas compositions, tests are done to investigate the mechanical response of several steel grades in reservoir conditions. Autoclave testing are done to observe possible cracking and corrosion attack on specimens, and the Hydrogen uptake in steel coupons is analysed by hot carrier gas extraction. Permeation tests are also conducted to test the effective Hydrogen diffusion in the steel.

Techno-economic feasibility studies are providing insights to support a decision whether to proceed to pilot and large scale demonstration projects. This work aims to inform decision makers in government and industry:
• Energy system modelling has been used to investigate the role of a widespread deployment of underground renewable hydrogen storage in EU-27 + UK in future scenarios across 2025-2050. The scenarios are based on several hypotheses on the hydrogen production (domestic vs. imports from non-EU), storage technologies (salt caverns, porous media, aboveground technologies) and spatial distribution (centralized or distributed storage and production). Preliminary result show that the required long-term hydrogen storage capacities range between 40 to 700 TWhH2 in EU-27 and the UK, i.e. 1.2 to 25 MtH2. As an order of magnitude, assuming it is only done through salt caverns, and that 4000 tons of H2 can be stored per cavern, it is 300 to 6250 salt caverns.
• An assessment of the regulatory framework for Hydrogen Underground Storage in Europe has been done, based on surveys throughout the industry and research institutes. Main barriers are identified and a ranking of countries is proposed according to the status of underground hydrogen legislation.
• Depleted fields or aquifers, salt caverns and possibly other surface technologies will become competing solutions to meet a local storage demand. The cost of developing each of them requires finding the most competitive. Cost model of subsurface storage options have been developed to support these analyses

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Hystories has already brought technical developments to hydrogen storage in depleted fields or aquifers, notably by recommending criteria to select sites, by gathering the reservoir candidates in a unique database at European scale, by setting a methodology to assess their storage capacity, and by classifying the microbial activity in aquifers based on a large brine sampling and laboratory work.

It has also brought insights to the decisionmakers by proposing a first storage demand estimation in each EU-27 member states, and by reviewing the legal framework throughout Europe. Last, it has built a cost model of the development of a new storage site to enable assessing whether underground storage can be competitive against other options.

Autoclave testing of the steel specimens

Overall workplan of the Hystories project

High pressure unit for microbial activity tests