Possible Breakthrough in Renewable Hydrogen: H2Pro

[SageBrush]

Researchers develop two-step method for efficient decoupled water splitting

The group reports a solution that scales and is 97.5% efficient.
I'm not sure about the speed of the process, the water requirements, if the heat required is part of the efficiency calculation, and nothing about reliability has been reported.

On the other hand the basic research comes out of a world class technical university and the founding members of the private H2pro are the original researchers so this bears watching. My fingers are crossed that the world may gain a sustainable, long term energy storage solution to replace natural gas.

 

[mblakele]

More info:

Fuel of the Future: Technion Researchers Have Developed an Inexpensive, Environmentally Friendly & Safe Hydrogen Technology – FuelCellsWorks

Technion researchers develop eco-friendly hydrogen production technology

https://www.h2pro.co/our-technology

This seems to be the original paper, from 2017 (paywall): Decoupled hydrogen and oxygen evolution by a two-step electrochemical–chemical cycle for efficient overall water splitting

Electrolytic hydrogen production faces technological challenges to improve its efficiency, economic value and potential for global integration. In conventional water electrolysis, the water oxidation and reduction reactions are coupled in both time and space, as they occur simultaneously at an anode and a cathode in the same cell. This introduces challenges, such as product separation, and sets strict constraints on material selection and process conditions. Here, we decouple these reactions by dividing the process into two steps: an electrochemical step that reduces water at the cathode and oxidizes the anode, followed by a spontaneous chemical step that is driven faster at higher temperature, which reduces the anode back to its initial state by oxidizing water. This enables overall water splitting at average cell voltages of 1.44–1.60 V with nominal current densities of 10–200 mA cm−2in a membrane-free, two-electrode cell. This allows us to produce hydrogen at low voltages in a simple, cyclic process with high efficiency, robustness, safety and scale-up potential.​

It looks like H2Pro is raising money to move this forward. At a guess I'd say it's 5-10 years away.

 

[cpa]

Looking at the nifty pamphlet and the chemical reactions--and it has been scores since I had any chemistry:

Please enhance or correct:

This will be in a closed, looping system whereby the water is changed into H2 and O2 via reduction. Over on the other side, the H2 is used for a fuel cell, while the hydroxyl ions form nickel hydroxide on the anode.

Then, this process is oxidized with O2 released into the atmosphere, and water is reformed to repeat the process.

Anyway, I assume that this process will require refueling with water periodically, right?

Did this paper analyze the effects of increased O2 in the atmosphere, or is my assumption wrong?

Where I get lost in the weeds is the total economic and atmospheric effects of this process. How much water per year will be necessary to accomplish this? What will be the ultimate end results of this process--and how will these results affect the planet? Are these addressed in the literature?

Ya gotta know that in California at least, water is our most precious natural resource. If we add yet another competing interest for water, and the pricing is such that agriculture is left out, this valley could dry up, as it were. In wet winters, water costs farmers anywhere between $1,500-$2,500/ ac-ft. Dry winters prices can exceed $4,000. (This is for non-project allocations.) There are roughly 326,000 gallons in an ac-ft. Retail prices of water can increase tenfold and still be a cheap source of "fuel" for this new process. It is unclear just how agriculture could compete if water demand goes way up.

With subsidence increasing too groundwater is not part of the equation.

Maybe desalinization is the answer. Maybe increased water usage is immaterial. I don't know. But I speculate that these researchers do not know either.

 

[acoste]

Looking at the nifty pamphlet and the chemical reactions--and it has been scores since I had any chemistry:

Please enhance or correct:

This will be in a closed, looping system whereby the water is changed into H2 and O2 via reduction. Over on the other side, the H2 is used for a fuel cell, while the hydroxyl ions form nickel hydroxide on the anode.

Then, this process is oxidized with O2 released into the atmosphere, and water is reformed to repeat the process.

Anyway, I assume that this process will require refueling with water periodically, right?

Did this paper analyze the effects of increased O2 in the atmosphere, or is my assumption wrong?

Where I get lost in the weeds is the total economic and atmospheric effects of this process. How much water per year will be necessary to accomplish this? What will be the ultimate end results of this process--and how will these results affect the planet? Are these addressed in the literature?

Ya gotta know that in California at least, water is our most precious natural resource. If we add yet another competing interest for water, and the pricing is such that agriculture is left out, this valley could dry up, as it were. In wet winters, water costs farmers anywhere between $1,500-$2,500/ ac-ft. Dry winters prices can exceed $4,000. (This is for non-project allocations.) There are roughly 326,000 gallons in an ac-ft. Retail prices of water can increase tenfold and still be a cheap source of "fuel" for this new process. It is unclear just how agriculture could compete if water demand goes way up.

With subsidence increasing too groundwater is not part of the equation.

Maybe desalinization is the answer. Maybe increased water usage is immaterial. I don't know. But I speculate that these researchers do not know either.

Fuel cell cars store around 5-6 kg Hydrogen. EPA range >300 miles
11.12% of water is Hydrogen by weight.

5kg H2 comes out of 45kg water assuming 100% efficiency.
45kg water is about 45.1liter ~= 12 gallon of water.


Average urban water usage per capita use per day in California in 2016 = 85 gallon.

Assuming one fills up the car once a week, that adds 1.7 gallon per day.

 

[SageBrush]

Did this paper analyze the effects of increased O2 in the atmosphere, or is my assumption wrong?

Water is electrolyzed into O2 and H2 from H20 ... and then the H20 is reconstituted when the H2 is either combusted or oxidized in a fuel cell. It is a closed loop.

As for the intermediate step of stored H2 before use, think moles:
one mole of H20 -> one mole of H2 and half a mole of O2
Molecular weight of H is one and O is 16
So 2 grams of H2 produces 16 grams of O2

---
A question for you: do you lose sleep over the LOSS of atmospheric oxygen as fossils are combusted ?

 

[nwdiver]

Did this paper analyze the effects of increased O2 in the atmosphere, or is my assumption wrong?

There are a lot of things that bother me about using Hydrogen for fuel.... that's not one of them.

When we burn hydro-carbon fuels to make CO2... where do you think the O2 comes from? We would probably have to store a years worth of energy as H2 before the change in O2 levels would even be measurable. >10 years worth before atmospheric O2 levels are as high as they were 10 years ago

Water 'usage' is also a rounding error. Roughly speaking the energy stored from splitting a gallon of water is more than the energy content of a gallon of gasoline.

And as @SageBrush pointed out... it's a closed loop. 2H2O => 2H2 + O2 => 2H2O