THERE IS NO GREEN WITHOUT BLUE: WATER’S ROLE IN CLEAN ENERGY TRANSITION By Mrs. Verónica García Molina Global Marketing Leader – Industrial Water & Energy DuPont Water Solutions The need for water to generate energy is
any type of raw water (river water, seawater,
getting a lot of attention, particularly given the
wastewater, etc..) to meet the required quality
growing interest in green hydrogen’s potential
of water for each process.
for the continued decarbonization of numerous industries. The water-energy nexus, with the inextricable linkage between the two, has long existed. With green hydrogen, the novelty between water and energy resides in the combination of the amount of “new” water needed and the timeline—by when that water is going to be needed. The obvious next question we need to ask ourselves is where is that water going to come from, particularly in regions already
According to a variety of sources, in order
facing water scarcity.
to produce 1kg of hydrogen, 9 to 13 Litres of ultrapure water (UPW) are needed and
A key component of the production of green
depending on the source of water used, the
hydrogen is the electrolyser, which electrically
real water needs can vary quite significantly.
splits the water molecules into hydrogen and
For example, to produce 1 L of Ultrapure Water,
oxygen gas. Within an electrolyser, ultrapure
3.3 L of Seawater are needed. This amount gets
water is needed as the feed stream and, if the
reduced by a half, i.e., 1.5 L if the source water is
production site accounts for cooling towers,
wastewater or surface water.
additional water will be needed. Intuitively, and given the global water scarcity Even though fit-for-purpose qualities of water
situation, the potential water sources often
are needed for the feed stream feeding the
considered for green hydrogen are seawater
electrolyser and for the cooling towers, the
desalination and wastewater. An interesting
reality is that technology exists to treat almost
figure, provided by Newborough and Cooley
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