Hydrogen Central

JRC Report – Blending Hydrogen From Electrolysis into The European Gas Grid

blending hydrogen electrolysis european gas grid

JRC Report – Blending hydrogen from electrolysis into the European gas grid.

Hydrogen is a strategic priority for the implementation of the European Green Deal. Its potential to store carbon-free energy in chemical form makes it an energy carrier option particularly suited for hard to decarbonise sectors such as industrial processes or heavy-vehicle transport, as a vector for renewable energy storage, or for stand-alone applications.

However hydrogen is mostly produced from fossil fuels and represents only a small fraction of the European energy mix.

To capitalise on the future prospects of the EU Green Deal in a comprehensive manner and to spur economic recovery from the COVID-19 crisis at the same time, the European Commission launched a hydrogen strategy for a climate-neutral Europe in 2020 (1) that sets out framework conditions and a list of actions for mainstreaming clean hydrogen.

It also includes milestone targets for installing at least 6 GW of renewable hydrogen electrolysers in the EU by 2024 and 40 GW of renewable hydrogen electrolysers by 2030. It is expected that elements of a new hydrogen infrastructure will be created gradually and that in the initial phase, demand will be met by production close to consumption sites.

The strategy also considers the blending of hydrogen in the natural gas network at a limited percentage as a further option to facilitate – in particular during a transitional phase – the uptake of hydrogen.

A range of studies and reports indicate that the presence of hydrogen in the gas grid up to a maximum of approximately 5-10% vol would be feasible without major modifications in the gas infrastructure and end consumer installations.

A further increase to 15- 20% vol appears feasible after modifications on system components based on current knowledge. Raising the content of hydrogen beyond that would require R&D for some categories of consumers and could be considered for the mid to long term.

Technical challenges aside, the regulatory framework must be in place for the strategy to achieve its goals. Enabling the access of renewable gases to the gas grid was marked as one of the key priorities in the European Gas Regulatory Forum in Madrid1 , which called for the creation of a market for renewable and low carbon gases.

The conclusions also proposed rules for the deployment of infrastructure along various pathways, including blending in the grid to guarantee broader availability of renewable and low-carbon gases for end-users.

Considering the capacity of the gas system to store energy as methane, injecting hydrogen into the gas grid might allow for an increased penetration of renewable energy in the system, in the form of green hydrogen (2).

Many EU countries are considering allowing the injection of hydrogen into their natural gas network, some of them defining blending targets to be reached in 2030 (3).

1 Overview of the methodology and input

The current study is an assessment, based on modelling, of the potential for renewable and low-carbon hydrogen admixtures in the European gas system as an interim first step towards decarbonising gas.

The study aims to identify the maximum electrolyser capacity that could be integrated with technical or economic criteria, the costs and benefits, the level of price support that may be required, as well as the impact of potential barriers, such as the existence of non-harmonised H2 blending threshold levels between member states. In particular the following questions are addressed:

  1. What are the electrolyser capacities that could be integrated under multiple assumptions on blending thresholds of H2 content in the gas networks? What is the optimal local H2 buffer storage at electrolyser facilities that will allow electricity generation and hydrogen production to match the constraints in the respective systems? How do these results relate to recently published H2 figures such as the H2 strategy?
  2. What will be the operating profile of the electrolysers in the above scenarios under (a) different market integration schemes and (b) varying assumptions of price support?
  3. What could be the implications of non-harmonised H2 threshold levels between member states on cross border trade and/or H2 generation?

Note : All results referring to the cost of hydrogen via electrolysis in the present study hold under the EUCO3232.5 scenario fuel and CO2 price assumptions and thus should not be considered as valid in market conditions such as those witnessed in the second half of 2021, when the unprecedented surge of the natural gas price occured.

1.1 Scenario setup and admixture thresholds

The study is conducted with METIS, by simulating the European power and gas systems jointly on a context based on the EUCO3232.5 scenario in 2030. The proposed modelling approach is based on one-node-per country, Europe-wide representation of the transmission networks of power and natural gas.

The analysis focuses on the inter-linkages between power and natural gas transmission networks, and does not consider the interaction between transmission and distribution systems.

The scenarios are parametrised in order to provide answers to the main questions posed above. This parametrisation is based on the following:

  1. The thresholds of H2 content in the gas network
  2. The market integration schemes
  3. Required price support schemes
  4. The adoption of non-harmonised H2 concentration levels

1.1.1 Thresholds considered for the admission of H2 into existing gas infrastructure

The technical readiness of existing gas infrastructure and end use equipment to handle safely and reliably hydrogen-natural gas mixtures is a topic of ongoing debate and research.

The technical association of the European Gas industry (4) recently published their views on the actual and mid-term future readiness of various components of the gas network to accept hydrogen-natural gas admixtures.

In particular, major components of the gas network and end-uses are able to accept 5-10vol% (depending on the end use) in natural gas without modification. After modifications and retuning of equipment this concentration is deemed possible to increase to 15-20%.

In power generation, gas fired gas turbines are sensitive to the gas composition, affecting the Wobbe Index, which is permitted to fluctuate in a given pre-set range. Thanks for staying up to date with Hydrogen Central.

Information provided by two major gas turbine manufacturers (5) (6) affirm the capability of a wide range of their gas turbine models to operate with natural gas – hydrogen admixtures at or above 15%vol. It is however stated that the “associated fuel system for the combustors are typically only configured for a maximum of 5%vol hydrogen and would require upgrading”.

Table 1. Admixture threshold levels

READ the latest news shaping the hydrogen market at Hydrogen Central

Blending hydrogen from electrolysis into the European gas grid, January 2022

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