Hydrogen Will Not Drink Europe Dry
Hydrogen strategies and drought are both high on Europe's agenda, and where they meet a question keeps coming up: will hydrogen production drain water supplies? Mostly not, according to a report published by the European Commission's Joint Research Centre (JRC) on 8 October. In the authors' words, Europe's hydrogen ambitions are achievable without major water crises, but only with proactive planning (Bolard et al., 2026).
How much water a kilogram of hydrogen needs
In theory, splitting water takes at least 9 litres per kilogram of hydrogen. In practice, cooling, keeping membranes hydrated and purifying the feed water push that up: manufacturers' data range from 10 to 22 litres. The JRC's announcement works with roughly 18–22 litres. Growing a kilogram of almonds, by comparison, takes about 1,000 litres (JRC, 2026).
At European scale, that is very little. The REPowerEU goal of 10 million tonnes of hydrogen a year by 2030 would take 0.08–0.12% of Europe's annual freshwater demand. The most ambitious 2050 scenario from the Clean Hydrogen Joint Undertaking, 67.5 million tonnes of renewable hydrogen a year, would take 0.57–0.82%. The 2030 goal alone would require around 140 GW of electrolysis capacity, 280 times the roughly 500 MW installed in early 2025.
Across Europe, hydrogen's water demand is negligible; the problems would be local, in drought-prone basins.
1,300 plants on the river-basin map
Averages say little, though, because water runs short locally. The researchers therefore combined several international and EU databases into a list of around 1,300 existing and planned hydrogen plants. They assessed each one within its own river basin: what share of renewable water it would take if all its water came from freshwater sources, a deliberately cautious assumption.
In 2023, 375 of the 404 operating plants, almost 93%, sat in basins where hydrogen production adds little pressure. Only 29 operated in areas that were already water-scarce. By 2030, the authors expect 91% of plants to add negligible or minimal pressure. The remaining 9% will not be the main cause of scarcity, but could aggravate existing problems in southern Europe, parts of France, northern Italy and Greece.
2050: one plant in ten in a sensitive spot
In the longer term, climate is decisive. On a moderate emissions pathway (RCP4.5), around 90% of plants would operate in 2050 in basins where hydrogen's water demand is small relative to available resources. On a pessimistic, high-emissions pathway (RCP8.5), 92 plants (8.4%) would sit in basins with a water exploitation index of at least 0.4, and another 25 between 0.2 and 0.4. Nearly one plant in ten would therefore be drawing a noticeable share of its basin's renewable water (Bolard et al., 2026).
Those plants would be in Greece, Spain, Italy, Portugal and parts of central Europe. The report does not single out individual central European countries. The authors stress that water stress in these regions would rise regardless of hydrogen: the problem is regional vulnerability, not hydrogen as such. In average years electrolysis barely registers, but during droughts it could make shortages worse in places. The report also cites the European Environment Agency's 2024 assessment, which found that water stress already affects 20% of Europe's territory and 30% of its population.
Water ranks sixth
One of the report's lessons comes not from the model but from a survey. In 2024 the JRC asked 26 hydrogen project developers what matters when choosing an electrolyser site. The availability and cost of renewable electricity came first; water supply came only sixth. Constraints on wastewater management ranked even lower.
Developers rank water only sixth when choosing where to build.
That matters because water regulation is fragmented. EU directives set general objectives, while concrete obligations are set nationally or even regionally. Permit thresholds, abstraction charges and the competent authority differ between member states and often between river basins. According to the report, two plants of identical size can face very different permitting routes and water charges depending on where they are built.
Seawater, wastewater, brackish water
The JRC's recommendations are aimed at developers and authorities alike (JRC, 2026):
- desalinated seawater in coastal regions, and treated wastewater and brackish water elsewhere, instead of freshwater;
- assessing hydrogen hub sites against basin-level water availability;
- water reuse infrastructure in industrial clusters;
- monitoring seasonal water stress and adjusting production to it;
- building the EU's new target of 10% better water-use efficiency by 2030 into project planning;
- assessing the environmental impact of desalination and direct seawater electrolysis.
For water utilities, this could also be an opportunity. If hydrogen plants run on treated wastewater, the effluent leaving a treatment plant could become a saleable resource, and proximity to a treatment plant could become an argument for siting an electrolyser.
The European Commission's Joint Research Centre (JRC) has mapped around 1,300 existing and planned European hydrogen plants against local water resources. Electrolysis needs roughly 18–22 litres of water per kilogram of hydrogen. Meeting the REPowerEU goal of 10 million tonnes a year by 2030 would take just 0.08–0.12% of Europe's annual freshwater demand. In 2023, 93% of the 404 operating plants sat in river basins where the extra pressure was low. Under a pessimistic climate scenario, however, nearly one plant in ten could be drawing a noticeable share of its basin's renewable water by 2050, in Greece, Spain, Italy, Portugal and parts of central Europe. Developers rank water only sixth when choosing a site. The JRC therefore recommends seawater, treated wastewater and brackish water instead of freshwater, and siting decisions made at basin level.
Hydrogen strategies and drought are both high on Europe's agenda, and a common question is whether hydrogen production will drain water supplies. A report published by the European Commission's Joint Research Centre (JRC) on 8 October is reassuring, but not unconditionally. The researchers mapped around 1,300 existing and planned European hydrogen plants against local water resources, assuming that every plant draws freshwater.
Electrolysis needs roughly 18–22 litres of water per kilogram of hydrogen; growing almonds takes about fifty times as much. Meeting the REPowerEU goal of 10 million tonnes a year by 2030 would take 0.08–0.12% of Europe's annual freshwater demand, and the most ambitious 2050 scenario 0.57–0.82%. In 2023, 93% of the 404 operating plants sat in basins where the extra pressure was low, and by 2030, 91% of plants will still add negligible or minimal pressure.
The picture worsens by 2050. Under a pessimistic climate scenario, nearly one plant in ten could be drawing a noticeable share of its basin's renewable water, in Greece, Spain, Italy, Portugal and parts of central Europe. The authors stress that the problem in these regions is existing vulnerability rather than hydrogen, although electrolysers could aggravate it during droughts. Meanwhile, developers rank water availability only sixth when choosing a site. The JRC recommends desalinated seawater for coastal plants, treated wastewater and brackish water elsewhere, and siting decisions taken at basin level. For water utilities, that could turn treated effluent into a saleable resource.
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