The project, developed by the joint venture Castellón Green Hydrogen S.L. —50% owned by both companies— exceeds €70 million in investment. According to the companies, all the main equipment is already installed on site, allowing the final stage of construction to begin before technical testing.
The facility will have a 25-megawatt electrolyser supplied by Plug Power, which will use renewable electricity from wind farms and solar plants through a power purchase agreement signed with Iberdrola. The system will enable hydrogen to be produced from water through electrolysis without direct carbon emissions.
Operational testing is scheduled for May 2026. During this period, the operation of the equipment, the stability of the electrolysis process and the integration of the plant into the energy system that will supply the facility will be checked before commercial production begins.
Once operational, the plant will generate approximately 2,800 tonnes per year of green hydrogen. This volume will be used mainly to replace part of the fossil-based hydrogen currently used at BP’s refinery in Castellón de la Plana.
Replacing this conventional hydrogen will reduce around 23,000 tonnes of carbon dioxide per year, a figure equivalent to approximately the annual emissions of 5,000 cars.
The project also has a significant industrial component. Around 25 Spanish companies are participating in different phases of development, supply and assembly of equipment, which strengthens the national value chain linked to renewable hydrogen technologies.
In addition, the initiative has technical support from the Energy Technology Institute and has received €15 million in public aid from the programme aimed at promoting the value chain of renewable hydrogen within Spain’s Recovery, Transformation and Resilience Plan, financed with European NextGenerationEU funds.
The Castellón plant is part of the joint strategy of BP and Iberdrola to accelerate the deployment of renewable hydrogen in energy-intensive industrial sectors. In particular, refining appears to be one of the areas where this technology can significantly reduce emissions associated with industrial processes.
Both companies also have plans to evaluate new phases of development at the Castellón industrial complex, with the possibility of expanding renewable hydrogen production capacity in the coming years. The aim is to advance the electrification of certain processes and progressively reduce the carbon footprint of energy and industrial activities linked to refining.
