How would we get water for large scale Hydrogen production?

[Jonas Knudsen]

So, I'm doing a project on fuel cells and therefore I am looking into Hydrogen production. Now the most promising one to me was Green Hydrogen. Or in other terms using renewable energy to drive electrolysis, creating Hydrogen and Oxygen.

But where would we get the water, without destroying whatever climate we're taking it from? I can't imagine sucking thousands of liters of water from a lake or the ocean to be a good idea.

 

Edited October 14, 2023 by Jonas Knudsen
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[exchemist]

9 minutes ago, Jonas Knudsen said:

So, I'm doing a project on fuel cells and therefore I am looking into Hydrogen production. Now the most promising one to me was Green Hydrogen. Or in other terms using renewable energy to drive electrolysis, creating Hydrogen and Oxygen.

But where would we get the water, without destroying whatever climate we're taking it from? I can't imagine sucking thousands of liters of water from a lake or the ocean to be a good idea.

 

Just think, for a minute, about the volume of water in the oceans. 

[studiot]

44 minutes ago, Jonas Knudsen said:

So, I'm doing a project on fuel cells and therefore I am looking into Hydrogen production. Now the most promising one to me was Green Hydrogen. Or in other terms using renewable energy to drive electrolysis, creating Hydrogen and Oxygen.

But where would we get the water, without destroying whatever climate we're taking it from? I can't imagine sucking thousands of liters of water from a lake or the ocean to be a good idea.

 

As exchemist says, one purpose of homework is to make you think.

So some things for you to think about : environmental science draws on many sicences disciplines.

 

I molecule of water produces 1 molecule of hydrogen on electrolysis.

The molar volume of water is about 18 x 10^-3 litres and the molar volume of hydrogen is about 22 litres so occupies over 1000 times as much volume as the parent water.

Electrolysing water produces what else.

Does it make a difference if that water is salt or fresh ?

How would you handle these other products ?

 

You said the hydrogen produced was destined for use as a fuel (in a fuel cell or otherwise)

What is the result of using hydrogen as a fuel ?

 

So why are you worrying about abstracting water ?

 

Have you studied natural environmental cycles such as the carbon cycle and the water cycle ?

[exchemist]

3 hours ago, Jonas Knudsen said:

So, I'm doing a project on fuel cells and therefore I am looking into Hydrogen production. Now the most promising one to me was Green Hydrogen. Or in other terms using renewable energy to drive electrolysis, creating Hydrogen and Oxygen.

But where would we get the water, without destroying whatever climate we're taking it from? I can't imagine sucking thousands of liters of water from a lake or the ocean to be a good idea.

 

Actually I was being stupid. The more basic point is that whatever water is used to make hydrogen is converted, when the hydrogen is oxidised in a fuel cell, to…….water! So it just becomes part of the water cycle, between atmospheric water vapour, rain and the oceans. 

[swansont]

5 hours ago, Jonas Knudsen said:

So, I'm doing a project on fuel cells and therefore I am looking into Hydrogen production. Now the most promising one to me was Green Hydrogen. Or in other terms using renewable energy to drive electrolysis, creating Hydrogen and Oxygen.

But where would we get the water, without destroying whatever climate we're taking it from? I can't imagine sucking thousands of liters of water from a lake or the ocean to be a good idea.

Does this process (the entire process) destroy water?

[mistermack]

5 hours ago, studiot said:

So why are you worrying about abstracting water ?

Well I'M worried about it, and that's why I'm trying to drink only beer. 

Someone's got to take responsibility. 

[Ken Fabian]

11 hours ago, Jonas Knudsen said:

So, I'm doing a project on fuel cells and therefore I am looking into Hydrogen production. Now the most promising one to me was Green Hydrogen. Or in other terms using renewable energy to drive electrolysis, creating Hydrogen and Oxygen.

But where would we get the water, without destroying whatever climate we're taking it from? I can't imagine sucking thousands of liters of water from a lake or the ocean to be a good idea.

 

Jonas - it is the relative scales that make water use a non-issue. The USA (as an example) uses about 100 billion litres of water a day just for household use.

The scale of hydrogen production from electrolysis is still very small but even at large scale it will not be a large user of water compared to many other uses. And energy sources like coal use a lot of water too, to wash the coal as well as reduce fire risks at mines and transfer facilities. More water is used again for cooling at power plants.

I expect overall use of water would go down with large scale use of hydrogen replacing fossil fuels.