The Hydrogen Connection: a decisive step towards energy sustainability in Spain and Europe

by Sergio Martín | Jul 5, 2024 | Technical articles

Recently, Spain and France have taken a significant step forward in their energy collaboration by agreeing on the shareholding of the future submarine hydrogen interconnection, a project that promises to transform the region’s energy landscape. This agreement not only strengthens the bilateral relationship between the two countries, but also underlines the importance of hydrogen as a fundamental pillar in the transition to cleaner and more sustainable energy. At the same time, Enagas has received proposals for green hydrogen projects that far exceed the Spanish government’s forecasts, which is evidence of a growing interest and remarkable dynamism in the sector.

H2Med: the underwater hydrogen interconnection

The submarine hydrogen interconnection between Spain and France, known as H2Med, which has already been discussed on the SynerHy website (H2Med vs SoutH2, the two possible H2 corridors in Southern Europe | SynerHy) is a flagship initiative with an estimated cost of around 2.5 billion euros. This infrastructure will have an initial capacity to transport 2 million tons of hydrogen per year, representing approximately 10% of the expected hydrogen consumption in Europe by 2030. H2Med will not only facilitate the transport of green hydrogen from production points to consumption centers but will also strengthen energy security and contribute to the decarbonization of the continent.

This project is a crucial step towards achieving the climate targets set by the European Union. The interconnection is expected to be operational by 2030, aligning with EU targets to reduce greenhouse gas emissions by at least 55% by that year. In addition, the interconnection will serve as a model for future hydrogen infrastructures, demonstrating the technical and economic feasibility of these large-scale projects.

Figure 1.  Proposed H2Med corridor. Source: 20 minutos

On June 24 in Madrid, Spain’s Enagás and France’s GRTgaz and Teréga, together with the German transmission grid operator OGE, signed a joint development agreement defining the terms of collaboration for the project. Under the terms of the agreement, the shareholding of the entity will be divided as follows: Enagás 50 %, GRTGaz 33.3 % and Teréga 16.7 %, thus the French and Spanish parties will contribute identical percentages.

As already mentioned in the technical article on the SynerHy website, H2Med will also include a joint venture between Spain and Portugal, called CelZa. In this part of H2Med, Enagás and Portugal’s REN have signed an additional agreement to the Memorandum of Understanding in force, with the aim of jointly developing and financing the studies for the development of the project.

Enagas and the rise of Green Hydrogen in Spain

The enthusiasm for green hydrogen in Spain is palpable. Enagás, the technical manager of the Spanish gas system, has received proposals for green hydrogen projects that exceed government expectations. Specifically, Enagás has identified a “base” scenario of projects to install 13.4 GW of electrolysers compared to the 11 GW contemplated for 2030 in the update of the National Integrated Energy and Climate Plan (PNIEC). These projects would have a combined production capacity of 1.6 million tons per year. In total, 650 projects from 206 companies have been submitted. Enagás has decided to classify the projects into production (65%), consumption (20%) and commercialisation (15%).

The base scenario takes into account projects with signed hydrogen sales and purchase contracts, in the construction or development phase or with already established developers, whose main focus is domestic consumption. The central scenario includes projects for export, where 23.3 GW of electrolysers will be installed with a production of 2.5 Mt per year. And in an optimistic scenario, called “maximum potential” by Enagás, 74.3 GW of electrolysers would be installed with a production of 7.9 Mt per year and a domestic consumption of 1.4 Mt per year.

Figure 2. National H2 pipeline transportation plan. Source: Enagás

These projects cover a wide range of applications, from the production of hydrogen from renewable energies to its use in industry, transport and electricity generation. Among the outstanding projects is the construction of electrolysis plants in different regions of the country, such as Andalusia, Catalonia, Aragon, Castile-La Mancha, Madrid, Castile and Leon and La Rioja, with the aim of harnessing the potential of the renewable energies available in these areas.

This portfolio of projects resembles the PNIEC forecasts, supporting in a very clear and resounding way the proposal put forward by the Government.

In this context, SynerHy presents itself as a key player in the promotion and development of green hydrogen. This platform is dedicated to fostering the adoption of hydrogen technologies through collaboration between companies, institutions and governments. SynerHy facilitates the creation of synergies that accelerate the implementation of innovative and sustainable projects by providing an enabling environment for the exchange of knowledge and resources. Its role is fundamental to connect the various actors in the hydrogen ecosystem and foster the creation of comprehensive solutions that respond to today’s energy challenges.

Green Hydrogen: A vector of change

Green hydrogen, produced through the electrolysis of water using renewable energy, is considered an essential energy carrier for achieving decarbonisation. Unlike gray hydrogen, which is produced from fossil fuels and generates carbon emissions, green hydrogen produces no greenhouse gas emissions during its production. This makes it a promising solution for sectors that are difficult to decarbonise, such as heavy transport, the chemical industry and steel production.

Spain and France’s commitment to the underwater hydrogen interconnection shows a shared vision of an energy future where green hydrogen plays a central role. This infrastructure will enable the efficient transport of hydrogen between the two countries, facilitating its use in various industrial and energy applications. It will also contribute to the creation of a European hydrogen market, promoting competitiveness and innovation in the sector.

SynerHy’s Role in Energy Transformation

SynerHy is positioned as a catalyst in this transformation process. The platform works to facilitate cooperation between different actors in the hydrogen sector, promoting research, development and implementation of advanced technologies. Through its network of partners, SynerHy drives projects ranging from the production of green hydrogen to its storage, distribution and end use.

One of the highlights of SynerHy is its ability to bring together diverse stakeholders, creating a collaborative ecosystem that fosters innovation. This collaboration is crucial to overcoming the technical and economic challenges associated with the mass adoption of green hydrogen. By promoting synergy between companies, research institutions and governments, SynerHy helps accelerate the transition to a sustainable hydrogen economy.

Figure 3. Telephony antenna decarbonisation project implemented by SynerHy. Source:

A Global Vision of the Energy Transition

The convergence of these developments the Spanish French collaboration, the rise of green hydrogen proposals, and the facilitating role of SynerHy highlights a crucial moment in the energy transition. It is not just about technological or economic advances, but about a paradigm shift in how we understand and manage our energy sources. Hydrogen, especially green hydrogen, is emerging as an indispensable component in the fight against climate change and in the quest for a more sustainable and resilient economy.

The underwater interconnection is not just an infrastructure project, but a symbol of international cooperation at a time when collaboration is more necessary than ever. Initiatives such as these demonstrate that the fight against climate change cannot be tackled in isolation; it requires a concerted and coordinated global effort. Spain and France are showing the world that it is possible to come together to create innovative and effective solutions that benefit everyone.

Challenges and Opportunities

Despite progress, the road to a green hydrogen economy is not without its challenges. The production of green hydrogen still faces economic barriers, as the cost of electrolysis and renewable energy remains high. In addition, the infrastructure needed for large-scale storage and transportation requires significant investments. However, growing interest and investments in the sector suggest that these barriers can be overcome over time.

International collaboration, such as that demonstrated by Spain and France, will be essential to address these challenges. By sharing resources, knowledge and technologies, countries can accelerate the adoption of green hydrogen and benefit from each other. Projects such as H2Med and platforms such as SynerHy are concrete examples of how cooperation can drive change and generate long-term economic and environmental benefits.


The alliance between Spain and France to develop the undersea hydrogen interconnection, the enthusiasm of the Spanish private sector reflected in the proposals received by Enagás, and the facilitating role of SynerHy, are unmistakable signs of a cleaner and more collaborative energy future. These advances are a clear demonstration that the transition to renewable and sustainable energy is not only possible, but also inevitable and beneficial for society and the environment. Green hydrogen is well on its way to becoming the heart of a new energy era, and Spain, together with its European partners, is well positioned to lead this exciting and vital journey.

In short, the hydrogen interconnection between Spain and France, along with the proliferation of green hydrogen projects and the role of platforms such as SynerHy, represent a significant move towards a sustainable energy future. These developments not only benefit the countries involved, but also mark a path towards a more united and resilient Europe in the face of the challenges of climate change and fossil fuel dependence.