[stephengillie]

It would free up more O2 and increase the amount of oxygen in the atmosphere. Eventually.

What would that do to greenhouse gases and global warming?If we converted (for example) 1% of the ocean to hydrogen, oxygen, salts, etc. Would air pressure increase? Or would the atmosphere simply expand?

Edit: Since everyone's confused about how I'd power it, I'd use solar power. Solar panels can easily output 1.5v today.

[JshWright]

This process still requires electricity to pass between the anode and cathode. It doesn't just magically split water.

To address your hypothetical though... Both would happen. Air pressure is just the weight of the atmosphere above you. If you add more gas to the atmosphere, it would indeed get 'bigger', and would therefore weigh more, resulting in higher air pressure.

[stephengillie]

Yes, this process requires so little electricity that it can be powered by scrap solar panels. I've got 2 at home that provide 1.5v each. TFA hasn't provided other details, such as required amperage.

[ars]

> Yes, this process requires so little electricity that it can be powered by scrap solar panels.

What?? The amount of hydrogen released is equal to 82% of the electricity input. Why are you saying "so little electricity"? If you have "so little electricity" you also have "so little hydrogen".

[stephengillie]

The process, as described, used 1.5v. That can be produced by a common solar panel. Thus we can scale it. And spread it across a small amount of time.

Did you and everyone think I was proposing to use gigawatts and electrolyse 1% of ocean water in a few seconds? O_o

[ars]

You can produce 100,000v by a common solar panel as well if you want. Voltage is completely irrelevant, what counts is energy.

> Thus we can scale it.

I don't follow. What does voltage have to do with anything?

> Did you and everyone think I was proposing to use gigawatts and electrolyse 1% of ocean water in a few seconds? O_o

Um, yes. Do you have the slightest idea how much energy it would take to electrolyze 1% of the ocean? I did some math for you: you need 1.752×10^26 joules. If you had a gigawatt available to you it would take 5,552,000,000 years.

[stephengillie]

I thought voltage, at a certain amperage, was a way of describing energy. Sorry for my confusion.

[ars]

???

It's powered by electricity. Where are you getting that electricity from?

[stephengillie]

The sun.

[ars]

Is this just a thought experiment? If not, why not use that sun-electricity for more useful things?

[stephengillie]

. . .

Yes, this is a thought experiment.

Were you seriously concerned that I had a solution for rising ocean levels?

[ars]

OK, in that case 1% of the ocean weighs 1.33×10^19 kilograms, the atmosphere weighs 5.1441×10^18 kilograms.

If you actually did this you would increase the atmosphere to 10 times it's current size - and most of that would be oxygen, unlike the current mostly nitrogen. Most of which would probably escape to space.

You'd have to find something to do with the hydrogen though, if you released it it would just recombine with the oxygen and make water again.

[Sapient]

Storing excess power generated during the day at night?

[ars]

I covered that in a different post, but hydrogen makes a very poor storage medium. The multiple conversions are also very inefficient.

[Semiapies]

Only if you had current hooked up to it.