According to Hydrogen Europe, producing one kilogram of hydrogen via electrolysis requires approximately 9 liters of ultrapure water, after upstream treatment from various sources such as groundwater, treated wastewater, or seawater. At scale, this equates to about 0.43 liters per kWh—comparable to gasoline and diesel on a per-energy basis and substantially lower than water-intensive fuels like bioethanol or traditional thermal power generation.
Hydrogen Europe estimates that the EU’s 2030 target of producing 10 million metric tons of renewable hydrogen would account for just 0.01% of current EU water abstraction levels. That’s significantly less than agriculture (40 billion tons) or the manufacturing sector (17 billion tons) across the EU.
Despite the small footprint, project developers face delays and legal complexity when securing water access. In countries like Spain, projects must interface with river confederations, regional authorities, and legacy water concession holders—often leading to protracted timelines that can double the maximum regulatory delays.
Moreover, competition for water with agriculture, municipal utilities, and industrial users intensifies in arid regions. Restrictions on brine disposal and limits on salt concentrations in wastewater effluent are forcing hydrogen developers to purchase and treat larger volumes of water than technically necessary, adding operational cost and infrastructure complexity.
The EU’s Industrial Emissions Directive now requires environmental assessments for hydrogen projects exceeding 50 tons per day. While the directive aims to balance environmental protection and industrial growth, guidance on best available techniques (BAT) for water-based electrolysis is still under development.
The inconsistency in permitting processes across member states compounds delays. In many cases, national-level ministries oversee major river systems, while regional entities manage smaller water bodies—creating a fragmented approval landscape that is ill-suited to the pace of clean energy expansion.
To mitigate freshwater dependency, several hydrogen projects are piloting alternative water sources. Treated wastewater and desalinated seawater are gaining traction, especially when paired with renewables to keep production emissions low. For example, a consortium in NEOM, Saudi Arabia, is constructing a desalination plant powered entirely by renewable energy, producing hydrogen with a marginal increase of just $0.05/kg.
Emerging technologies like direct seawater electrolysis—successfully piloted by Dongfang Electric in China—could eventually bypass desalination altogether, reducing both water use and treatment costs. However, these remain in early-stage development and face hurdles in membrane efficiency, purification, and environmental safeguards.
The narrative that hydrogen is water-intensive lacks nuance. On a systems level, hydrogen’s water needs are modest compared to other fuels and sectors. Yet, for project developers, navigating regional permitting regimes and securing sustainable water access can present real challenges that delay deployment.
As Europe races to meet its RePowerEU hydrogen targets, policymakers must streamline permitting, expand BAT guidance, and promote circular water use strategies—such as pairing hydrogen hubs with municipal wastewater plants or industrial parks.
