Moeve has taken a decisive step in Europe’s hydrogen race, approving FID for the first phase of the Andalusian Green Hydrogen Valley, a 300 MW project branded Onuba with expansion potential to 400 MW. With a total investment of more than €1 billion including associated infrastructure and a dedicated photovoltaic plant for self consumption, this is not a pilot. It is an industrial scale commitment.

The project will be developed in partnership with Masdar and Enalter, majority controlled by Enagás Renovable, with Moeve holding 51 percent. Backed by €304 million in Spanish government support under the EU NextGenerationEU H2 Valleys framework and recognized as a Project of Common European Interest, Onuba is clearly positioned as a cornerstone of Spain’s green molecule strategy.

From an EPC perspective, this is where the real story begins.

At 300 MW, with an option for an additional 100 MW subject to grid capacity and board approval, Onuba will produce around 45,000 tonnes of green hydrogen annually. The output is targeted at renewable fuels for road, aviation and maritime transport, alongside feedstock for chemicals and fertilizers. The decarbonization impact is significant, with roughly 250,000 tonnes of CO2 emissions avoided per year.

Technology suppliers and scope opportunities

Although the detailed contract awards have not yet been disclosed, the technology stack will be critical. Players such as Siemens Energy and thyssenkrupp nucera are natural contenders for large scale PEM and alkaline electrolyzer packages in projects of this size. Both companies have been active across Iberia and broader Europe in securing multi hundred megawatt hydrogen contracts, and Onuba sits squarely within their addressable market.

For EPC contractors, the opportunity extends far beyond the electrolyzer skids.

Based on EPCIntel.com database benchmarks for 300 to 400 MW hydrogen hubs in Europe, the typical capital allocation for a €1 billion scale development can be broken down as follows:
- Electrolyzer systems and balance of plant, 35 to 40 percent, or roughly €350 to €400 million. This includes stacks, rectifiers, transformers, cooling systems, demineralized water units and integration works.
- Power infrastructure, 15 to 20 percent, around €150 to €200 million. This covers grid connection, substations, high voltage cabling and internal distribution.
- Hydrogen compression, storage and handling, 10 to 15 percent, or €100 to €150 million. Storage tanks, compression trains, safety systems and export interfaces fall into this scope.
- Dedicated renewable generation, in this case the self consumption PV plant, 15 to 20 percent, translating to approximately €150 to €200 million depending on capacity and land conditions.
- Civil, structural and utilities infrastructure, 10 to 15 percent, roughly €100 to €150 million. Foundations, buildings, water treatment, fire protection and site development are included here.
- Engineering, project management and contingencies typically account for the balance, around 5 to 10 percent.
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This breakdown highlights the scale of subcontracting and supplier opportunities across electrical equipment, compression systems, storage tanks, EPCM services and specialist installation contractors.

Strategic positioning in Spain hydrogen buildout

Onuba is not an isolated investment. It forms part of a broader Andalusian Green Hydrogen Valley concept and Moeve’s Positive Motion strategy to pivot toward low carbon molecules. Spain has set ambitious hydrogen capacity targets, and projects like this are essential to anchor domestic demand in refining, chemicals and export oriented fuels.

Masdar’s participation signals confidence from a global clean energy investor with a growing hydrogen portfolio. Enalter and Enagás Renovable bring pipeline and renewable gas expertise, crucial for future hydrogen transport and integration into Spain’s backbone network.

The recognition as a PCI project gives Onuba strategic weight at the European level. It also improves the bankability profile, particularly if the 100 MW expansion moves forward.

For the supply chain, the coming weeks will be critical. As construction begins, expect phased EPC awards covering site preparation, utilities, power connection and eventually full electrolyzer package contracts. Contractors with hydrogen references, grid integration experience and strong local content capabilities in Andalusia will be well positioned.

With more than €1 billion committed in phase one alone, Onuba moves Southern Europe from ambition to execution. The hydrogen buildout is no longer theoretical. It is entering the procurement cycle, and the EPC market should be watching closely.