Hydrogen network: RHYn project explained by GRTgaz

The RHYn project is a 100 km network to transport hydrogen in Alsace, with interconnections planned with Germany and Switzerland.

GRTgaz is in charge and plans to complete the first phase by 2028. This program was the subject of a webinar organized on Tuesday, August 30, 2022 by DinamHySe.

From natural gas to hydrogen

With a network of 32,500 km of pipelines, GRTgaz transports 646 TWh of gas annually in France. Its strong European presence is supported by a staff of around 3,000 employees who meet the needs of 742 industrial customers, plus 19 connected distributors.

Recognized as an operator of “vital interest”, the company complies with an economic model controlled by the CRE (Commission de régulation de l’énergie). With the new need to develop decarbonated energies produced in France, GRTgaz is now also positioning itself on hydrogen, after having for a long time had as its main occupation everything that could revolve around the transport of natural gas. This is why, thanks to its expertise and know-how, the group is now at the heart of vast projects that are helping to develop the use of the H2 molecule in industry and for mobility.

53,000 km of hydrogen pipelines by 2024

As part of the European hydrogen backbone, the dedicated transport network should include 28,000 and 53,000 km of pipelines in 2030 and 2040 respectively. According to Jana Kavicka, Hydrogen Business Developer for GRTgaz: In France and in 8 years, “hydrogen consumption will still be mostly local and concentrated in industrial zones such as Dunkirk, Le Havre, Paris, Lyon, Marseille and Lacq”. It expects local networks to grow to 1,000 km in these first industrial clusters.

“The vision we have of the networks to be deployed does not constitute a commercial commitment by GRTgaz,” she stressed. In 2040, according to a scenario put forward by France Hydrogène with the strategy consulting firm McKinsey, French demand would be around 110 TWh per year. “If the network seems to be less dense in France, especially compared to the Netherlands, it is because of the national strategy which wants to promote the construction of electrolysers at the foot of the factories requiring hydrogen, and then develop a vast network,” said the representative of the operator.

For the growing needs in hydrogen supply, GRTgaz is once again taking on the role of “an independent transporter that will provide an open structure”, Jana Kavicka stressed. And this in an organized market based on 3 main principles: competitive prices and optimization of assets; security of supply; balancing and access to storage capacities. “GRTgaz does not store, but provides interconnection with storage sites,” she said.

“At least half of the network would be made up of the conversion of existing pipelines. To meet specific needs that are no longer current, sections for the distribution of natural gas have been doubled. In this case, one of the two lines would be recovered for hydrogen,” she said. With a coating on the inside or outside to ensure a good seal? “After various checks to eliminate leaks, especially at the weld level, a coating could eventually cover the pipes. It is just a track today, but nothing is decided at this time,” replied the speaker.

A separate network

In the Grand Est region, GRTgaz is involved in the cross-border programs mosaHYc (Moselle Saar HYdrogen Conversion) and RHYn (Rhine HYdrogen Network). The 2 networks could one day be connected together. But it is for the Alsatian network that DinamHySe, representing the H2 sector on the territory, organized a presentation webinar on Tuesday, August 30. The aim is to connect consumption with low-carbon hydrogen production in a safe and efficient way. A possible interconnection with the natural gas network, for example in case of overpressure? “No, because they are two separate closed networks. In addition, it would not be viable for certain customers who cannot work with a high level of hydrogen in natural gas. That’s why we have a 6% limit today,” says Jana Kavicka.

What about the purity of the hydrogen delivered? “Our target is 98%. We don’t want to commit ourselves to levels that we can’t keep. If this rate is insufficient, for example for mobility, then we will have to install an output filter for, and with, the customers concerned. This will be less expensive than having to maintain 99.999999% purity throughout the network,” she explained.

30 bars

“In the network, the hydrogen should circulate at a pressure of 30 bars, which is the production pressure. We started our tests with lower values and then observed what happened to the tightness. We gradually increased the pressure. Because of the interconnection, it is possible that it will be increased to 50 bar in some sections,” said Jana Kavicka. The diameter of the pipes will generally be 400 mm, with sections likely to be 250 mm at the interconnections.

Will hydrogen be odorized, like natural gas, to detect possible leaks? “It’s not clear. Probably not. This is actually done for natural gas in France, but not in Germany,” compared the GRTgaz representative. “The monitoring could be done by drone, tracking of the pipes, and by means of regular inspections. We will see this later. These decisions are not made during the feasibility study where we are today,” she added.

The needs

Sitting on Switzerland, Germany and France, the Upper Rhine is accumulating hydrogen needs for the chemical, food, glass manufacturing and transportation sectors. “There are already 60,000 tons per year in this area […] There is a relatively complete ecosystem with great potential for development,” said Jana Kavicka.

If we look at mobility alone, there are 3 airports and 5 ports on the river. In addition, 13,000 heavy goods vehicles pass through the Mulhouse area every day. In order to prepare for a shift from diesel to hydrogen, the opening of 4 dedicated refueling stations is already planned in the Haut-Rhin. Faced with these needs, projects are emerging for the production of this gas. Hence the RHYn program, which will supply all the applicants installed in the region. In its entirety, the network will be composed of 100 km of pipelines, 60 km of which will be converted. At a rate of 160,000 m3 per hour, this network will have a capacity of 125,000 tons per year, or the equivalent of about 900 MW of electrolysis.

3 phases

The RHYn hydrogen network will be developed in 3 phases. The program is currently undergoing a feasibility study for the first phase, dedicated to the section between Fessenheim and Ottmarsheim.

“The project should revitalize the Fessenheim area affected by the closure of the nuclear power plant. In addition, because of the presence of the nuclear power plant, the size of the electricity grid is well suited to supplying electricity to the electrolysers that will be installed in the vicinity,” commented Jana Kavicka.

“Is there any plan to extend the grid to Strasbourg? “It all depends on the needs of the customers. We are currently in the middle of prospecting and studying the demands of industrialists and for mobility,” replied the GRTgaz representative. “As far as interconnections are concerned, the state of Baden-Württemberg is interested. Switzerland, for its part, already knows that it will not be able to produce all the hydrogen it needs on its territory. Discussions are underway with transporters and distributors in these two countries, but it is still too early to talk about it”, the speaker assured.

With the idea of operating the future system for more than 25 years, from 2028 and the opening of the Fessenheim-Ottmarsheim section, GRTgaz is following a relatively flexible roadmap. It began in 2021 with a consultation with all the players in the basin potentially concerned. This involved drawing up an initial list of those interested in a connection, locating the sites, identifying the volumes to be transported from an injection point to an exit point and with what flexibility, then the pressure constraints, the quality of the gas, etc.

This opportunity study allowed the operator to make a non-binding proposal detailing: the characteristics of the network (route, transport capacity, pipeline conversion, technical equipment, etc.); the quality of the hydrogen transported; the deployment schedule; the costs and tariffs; the terms of the contracts (duration of the commitment, pricing principles) This leads to the current feasibility study phase, which is necessary to formulate a binding proposal that will include a financing plan and will be conditioned by a minimum number of interested parties, the obtaining of subsidies, etc. Without any great rigidity, the schedule shows a start of construction in 2026, for a duration of 1 to 2 years.

“The more customers there are, the lower the costs will be,” insisted Jana Kavicka. It is still possible today to make oneself known to GRTgaz to join the list of future players connected to the RHYn hydrogen network. “The commitment of a certain number of players is essential to trigger the investment decision and build a new infrastructure,” he said during the presentation.

This impetus also makes it possible to identify potential synergies and to plan the work within a set timeframe. While the key dates in the roadmap can still be adjusted, the speaker estimated that the period between the feasibility study and the construction of the network is at best 5 years. The injection points have already been identified, so as to ensure the balancing of the network with the consumer players. “Some customers may have consumption needs, but also punctually injection needs,” said the speaker.

Storage, production and numbers

There is talk of storing hydrogen in salt caverns. “The storage depends directly on the different projects but also on the quality of the land. We are in contact with Storengy and other operators on this subject,” added Jana Kavicka. “Here again, storage must be done while seeking to balance the gas network. There will undoubtedly be developments to be made in this direction for the RHYn program,” she warned. “Initially, there won’t be too many constraints on how hydrogen is produced. It’s an open network. It will just be a matter of the gas meeting the required specifications. It will be increasingly green afterwards,” she projected.

And what about the volume of investment and the transportation tariff? The speaker did not want to give precise figures that have not yet been announced. She did, however, give some orders of magnitude: “several tens of millions of euros” for the envelope needed to complete the project, and “an average transport cost of between 0.10 and 0.20 euros per kilogram of hydrogen for 1,000 km”.