Powerfuels Brief: Water consumption for the production of green hydrogen

As part of our ‘Powerfuels Brief’ series, the Global Alliance Powerfuels hosted a digital event on October 25, 2021, to discuss an aspect linked to the sustainable production of renewable hydrogen that is of increasing interest: water consumption. Presenting insights from the Alliance’s analysis and discussion paper on the topic, our experts, together with three expert guest speakers, discussed recommendations to ensure that the water needed for the production of green hydrogen and green hydrogen derivatives is sourced and consumed sustainably.

Water consumption is gradually gaining more attention in the discussion on sustainability of powerfuels, as ramping up global production capacities of renewable hydrogen and powerfuels would lead to a significant water demand. An airplane flying from London to New York operated on 100% green hydrogen-based kerosene would require 550,000 liters of water for the production of said kerosene, or as much as the daily water consumption of 1,800 US citizens.

Considering that optimal production sites for green hydrogen often reside in water scarce areas, ensuring environmentally sustainable water extraction and consumption practices is imperative to ramp-up and sustain global production capacities.

With European legislation lacking concrete sustainability criteria for water consumption for the production of powerfuels, the Global Alliance Powerfuels gathered industry and policy experts to discuss challenges and potential solutions in a digital event as part of our ‘Powerfuels Brief’ series on October 25, 2021.

Our experts Matteo Micheli and Friederike Altgelt presented insights from the Global Alliance Powerfuels’ recently published discussion paper on the water consumption of powerfuels. In the paper, we contextualise the relevance of sourcing water in an environmentally sustainable way for the market ramp-up of powerfuels. Specifically, we first quantify water consumption for the production of renewable hydrogen and other powerfuels such as e-kerosene, and then outline approaches to map water availability in powerfuels-producing regions. In addition, we provide specific policy recommendations to foster environmentally sustainable water consumption and avoid water stress.

The presentation of the Alliance’s analysis and recommendations was followed by presentations and a moderated discussion with three external expert speakers.

Rivash Panday, Specialist for Sustainable Water at Sasol, emphasised the role of water as a feedstock fundamental to realising the company’s ambitions in delivering more sustainable fuels and chemicals, including green hydrogen and its derivatives. Mr. Panday shared that Sasol has adopted a stewardship approach to mitigate water risk based on elements such as supply chain management, collective action, and transparency. He further outlined several potential solutions Sasol is investigating for achieving its green hydrogen ambitions while operating in water scarce areas. This includes, but is not limited to, surface water conservation measures, desalination of seawater, and the use of filtered greywater.

Luciana Mendes, Business Developer for Clean Tech at Alfa Laval, highlighted how desalination is a proven technology which can be employed in a variety of scenarios, e.g. for producing green hydrogen offshore. Ms. Mendes elaborated that in the case of hydrogen production specifically, waste heat from electrolysis can be used in thermal desalination to vaporize and demineralize seawater cost-effectively. Thermal desalination would also present the co-benefit of requiring fewer amounts of antiscalants and rust-inhibitors compared to conventionally used reverse osmosis desalination. Ms. Mendes also echoed the Alliance’s recommendations on handling and processing brine to lower its environmental impact.

Jörg Baur, Senior Energy Expert at GIZ, stated that water supply is a minor cost factor in the production of green hydrogen. He added that criteria to foster social sustainability should also be addressed and considered in the discourse, highlighting that the effect on local communities should be minimised, considering in particular that water stress is a likely issue in many locations with favourable conditions for hydrogen production. Mr. Baur added that desalination was a good solution for most locations, yet land use from desalination and brine disposal should be minimised, as they have a significant impact on local populations and nature.

One possible approach to include a social sustainably dimension to desalination would be to foster the co-benefit of additional freshwater production for local communities, e.g. for agricultural uses. According to Mr. Baur, by partnering with governments and local administrations, it could be possible to conduct impact assessments of green hydrogen production facilities, which would include, among others, land use planning and water consumption.

The event was concluded with a Q&A session during which our experts and the panellists addressed questions from the audience. All speakers agreed that while the topic of environmental sustainability of water consumption for the production of powerfuels is gaining traction in the public and policy discourse, defining effective and implementable sustainability criteria should become a priority, as few concrete proposals exist to date.

With the event and the affiliated publication, the Global Alliance Powerfuels sets a starting point for the discussion on addressing this additional pillar of the environmental sustainability of powerfuels and its incorporation into hydrogen regulation.

For further information, please contact our experts:

The speakers’ presentations are available for download below:

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