Plans for a large-scale green ammonia plant in El Serrallo’s industrial zone, between Almassora and the Grau de Castellón, have met resistance from residents and environmental groups, with political parties also joining the opposition. The project is led by Armonia Green Castellón, SL, a subsidiary of Spanish group Ignis. Ignis partnered with the US-based KKR fund through their joint platform, Ignis P2X. The plant aims to produce more than 500,000 tonnes of green ammonia annually for export. Ignis and KKR established Ignis P2X in 2024 to develop green hydrogen and ammonia projects for industrial use, particularly in sectors that are difficult to electrify. The plant’s scale, potential safety hazards and lack of direct benefits for local industry have made it a flashpoint.
The opposition, organized under the No Armonia Green platform, is seeking to submit technical objections to the regional Ministry of Environment before the July 13 deadline. Compromís, a regional political party, has also urged the Almassora council to formally oppose the plant. Company data show that the facility would occupy 200,000 square meters and require an investment of €1.656 billion, with production scheduled from 2025 to 2033. That figure is separate from funding announced for Ignis P2X as a whole. In October 2026, Ignis and KKR injected €60 million in liquidity into the platform: a €30 million capital increase through loan capitalization, plus a further €30 million in direct cash.
Supporters say the project would position Castellón as an international energy hub and reduce CO2 emissions by 1.2 million tonnes. Detractors see a business venture that exposes the region to the risks of handling a highly toxic substance, while all the ammonia produced would be shipped to northern Europe. Local industries, especially the ceramics sector, would not benefit from the ammonia, which is made using renewable hydrogen and is considered impressive to industrial decarbonization. Ignis P2X’s wider portfolio includes Armonía Green Galicia, a hydrogen-valley project in A Coruña developed with Repsol, and Armonía Green Burgos, part of the consortium developing the Hydrogen Valleys of Castilla y León.
Technical reports from local authorities have added weight to the concerns. The Almassora council has called for continuous monitoring of noise and odors, citing their cumulative impact in an already dense industrial area. The Castellón city council has highlighted the risk of a “domino effect,” in which an incident at one facility could trigger a chain reaction across the industrial zone. The area is home to high-risk installations, including the BP refinery and chemical plants. The proposed facility would also occupy more than 30% of land previously reserved for a strategic logistics platform, potentially limiting future development.
Environmental groups say their objection is to the scale and location of this particular project, not to ammonia production or decarbonization. They point to the dangers posed by two storage tanks with a combined capacity of 56,000 tonnes of ammonia. In a major accident, a toxic cloud could threaten urban areas within a four-kilometer radius. Critics are calling for the publication of safety and self-protection plans. They have also raised concerns that the route for transporting ammonia to the port could put nearby facilities at risk.
A report dated July 2025 from the Generalitat’s Agency for Security and Emergencies found the company’s safety measures insufficient to mitigate the impact of a potential accident. The agency called for the project to be redesigned with additional protections for the population.
Another major point of contention is that all the ammonia produced would be exported, with none supplied to local industries. Environmentalists argue that Castellón would bear the environmental and industrial risks without gaining direct benefits from the energy transition. The project is expected to create around 100 permanent jobs, raising questions about its social return given the scale of the investment.
The plant’s “green” credentials are also under scrutiny. It would require up to 850 megawatts of power, about a quarter of the Valencian Community’s annual electricity consumption, and use five million cubic meters of desalinated seawater each year. The company says all energy will come from renewable sources, but critics argue the plant will sometimes rely on gas-fired power. They also question the environmental impact of discharging four million cubic meters of brine and industrial wastewater into the port, which could affect nearby marine ecosystems and protected areas.
Opponents say they support renewable energy but want more considered planning for the size and location of such projects. They cite BP’s smaller-scale, locally focused hydrogen project as a more appropriate model. Independent reporting describes a separate 25 MW electrolyzer in Castellón, intended to supply BP’s refinery, as undergoing testing ahead of commercial operation. It is distinct from the proposed Armonía Green ammonia plant. The plant’s promoters had previously considered locations including Tarragona and Sagunto before choosing El Serrallo. The current mobilization aims to draw public attention to the project’s risks and consequences, challenging the idea that an environmental label alone justifies large-scale industrial development in the region.
Green ammonia is increasingly seen as part of the global push for decarbonization, especially in shipping and heavy industry. Spain, with its access to renewable energy and strategic ports, is positioning itself as a future exporter of green fuels. Ignis P2X’s projects in Galicia and Castilla y León show the broader national portfolio behind the Castellón proposal. The Spanish Ministry for the Ecological Transition awarded €129.3 million in aid to Armonía Green Galicia for its hydrogen valley in A Coruña, developed in partnership with Repsol. That award documents public support for an Ignis-linked project elsewhere in Spain; it is separate from the proposed Castellón plant. The Castellón case highlights the challenge of securing local acceptance and integrating large-scale energy projects with existing industries.
