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New efficient way to split h2O to create Hydrogen!

Australian scientists have successfully performed a new super efficient sea water splitting technique to create hydrogen.

http://media.uow.edu.au/news/UOW150897.html

http://sciencealert.com.au/news/20131206-24477.html

Damn I was hoping that the overall energy needed to greate Hydrogen went down. But this is good news too. At least nobody will sell water to a company to let people die on thirst.

@ ChristianG

How about this for energy efficiency to free Hydrogen molecules? Just needs light.

"We've developed a method by which molecular hydrogen-producing catalysts can be interfaced with a semiconductor that absorbs visible light"

http://www.labmanager.com/?articles.view/articleNo/37314/title/Hydrogen-...

Maybe not there yet, but looks promising... :)

haha 3 months later.

and the flying cars will be here by the 1960's

Milestones are easy.
Complete technology ready for consumers, not so easy.

(except for the Tesla!)

Flying cars are here: they are called helicopters.

Problems with this kind of techs are infrastructures and price. Hydrogen will never break through because it is not needed. In order to break through it would need to be considerably better than alternatives and it would require infrastructure.

@ChristianG - Why were you hoping it went down? :S

Timo, your assumption of the need for infrastructure for a H based economy comes from where? Once separating hydrogen becomes efficient enough anyone can have their own hydrogen production facility at their home or office. Even today, with really low efficiency numbers, there are many people who are already 100% power independent and off grid thanks to hydrogen.(http://www.hydrogenhouseproject.org)

What kind of infrastructure are you refering to? You only need solar panels and water...

In other news:

Solar Hydrogen Production Efficiency World Record Broken at a whoping 5.3%, getting closer to the 10% mark!

Read more at http://cleantechnica.com/2013/09/27/solar-hydrogen-production-efficiency...

asumption for*

In your dreams.

Using electricity to produce hydrogen is waste of energy even if you can do it at home. Why not use electricity directly? Get an UPS for power outages (IE: bad weather).

With infrastructure I was referring HFC cars. You need filling stations just like gas stations. No one has hydrogen in their garages, everybody has electricity.

That infrastructure will never born. It's just obsolete already.

Timo;
+1

I'm not saying that Hydrogen is ready for primetime, not by a long shot. But I do see hydrogen as a possible solution to the world's energy woes in the future (a couple of decades). I think once the milestone of producing Hydrogen with less electricity than the energy density of the resulting Hydrogen is achieved, we will be there. It’s not so farfetched, a lot of progress has been made in the last few years.

Timo, I think I have to disagree with your notion that HFC cars need the equivalent of gas stations to be filled up. Just look at the link that I posted; the owner of the house has his own hydrogen "filling station", this is because he is producing the hydrogen himself, from sun light! Maybe not very efficiently but remember Hydrogen is a much better medium for storage than any battery available right now, energy density per volume is a lot higher and there is no loss of energy through time or because environmental factors. Check this blog from Tesla Motors Club where Hydrogen is used by a Model S owner primarily as an energy storage medium.

http://www.teslamotorsclub.com/entry.php/123-Going-Off-Grid-Powering-hou...

On my part I do hope we get there, a hydrogen based energy economy would mean the end of so many problems caused by today's energy production and distribution model; no more pollution, no more infrastructure barriers, etc. Like I said it might seem far fetched, but hey, if you had told me just three years ago that today there would be an electric car as practical for everyday use and roadrips and with the range, performance and technology as the Model S I would have been very skeptical...

I agree that hydrogen for energy has no appeal except for military applications and off-griders, perhaps. I'm no expert, but I would assume that any technique to make hydrogen out of abundant sea water, and conveniently, could be great news for the material industry and as a lifting gas. Ever notice how everyone thinks of helium for a lifting gas, which is unsustainable because it escapes even the atmosphere, but forgets about hydrogen? I know, hydrogen can pop, but does it really matter if a birthday balloon were to explode? In a blimp, there must be ways to plan for in case the hydrogen pops, or to not use flammable or static-prone material to cover the blimp in the first place. Oh, well, helium must still be cheap so long as oil and gas is cheap and the industry needs to get rid of that by-product. One day, people will need hydrogen and technology that helps us get it will become more important.

frmercado "[...] producing Hydrogen with less electricity than the energy density of the resulting Hydrogen [...]"
Hold on there, what are you suggesting? Not trying to open another perpetual motion machine argument, here, I hope. You will always end up with hydrogen worth less energy than the energy it took to split it from water, always... unless fusion power is what you have in mind.


I think once the milestone of producing Hydrogen with less electricity than the energy density of the resulting Hydrogen is achieved, we will be there.

In other words, you want to repeal the second law of thermodynamics.

Good luck with that.

In other news, I weep for the state of scientific literacy in this country.

Dramsey: exactly, which could explain why climate change deniers, creationists, and other propagandists haven't been stoned out of town, yet.

DRamsey;
+1

TR;
Even with fusion. The energy from the fusion plant used will always exceed the energy stored.

@frmercado;

Hydrogen is a much better medium for storage than any battery available right now, energy density per volume is a lot higher and there is no loss of energy through time

Both claims are plain wrong. Hydrogen beats batteries in weight, but lose at the volume, especially once you add the volume of the actual hydrogen fuel cell in the equation. Even weight is questionable when added that FC. Other thing is that hydrogen seeps thru pretty much any material, so you do lose it over time. Not quite as fast as batteries lose energy but it does happen.

@Everybody else; frmercado said "less electricity", not less energy. By microbes or something else.

@Dramsey and Brian.

What does thermodynamic equilibrium has to do with anything?

Hydrogen separation its a chemical process and it's not subject to the 2nd law of thermodynamics. You are NOT producing or generating energy, you are just separating a molecule from other molecules. The only thing is that this molecule (H) by itstelf (when it is not attached to other moleculues like oxigen to form a third molecule like water)has one the highest energy density values per mass. Its energy density is between 120 and 142 MJ/kg. This means that for every 1 kg of mass of hydrogen, it has an energy value of 120-142 MJ. There is a differnce between a physical process and a chemical process.

Its like saying that refining oil could never be achieved because it would violate the 2nd law of thermodynamics! Yeez, someone missed their chemistry 101 during highschool and probably their physics 101 too. :)

Indeed I weep for the state of scientific literacy in this country, when people cannot differenciate between a chemical process and a physical one...

Here is a link to a website with a rundown of what the 2nd law of thermodynics involves, beware it involves a thing called mathematics, and if you didn't go through your basic physics and chemystry you probably wont be able to understand this and the diference between separating a Hydrogen molecule from water to then use that molecule as an energy source versus attaching a fan to a moving object to "produce" energy from that object to keep it moving.

http://2ndlaw.oxy.edu/entropy.html

Furthermore, if you don not understand what perpetual motion really is do not use it as an example when you don't know if its being used or not...

@ Timo

Hydrogen weights more than a battery? Really?

Helium is composed of 2 Protons, 2 Electrons and 2 Neutrons.

Hydrogen in it's most stable form is a molecule H2 which is composed of 2 Protons and 2 Electrons.

Protons and Neutrons has similar weight and we disregard electrons as their mass is not significant. So He has 4 and H2 has 2, which makes Helium twice as heavy as H2.

A tank FILLED with hydrogen is actually LIGHTER than when it empty...

Protons and Neutrons have* similar

"Hydrogen separation its a chemical process and it's not subject to the 2nd law of thermodynamics. "

LOL!

So many errors, so little time ...

@frmercado, you need to read my post again. I said that volume of the hydrogen is bigger. Also when you add fuel cell to that equation then weight is also questionable (in cars). It is inefficient and expensive.

What does helium do in all this?

Everything is subject to laws of thermodynamics.

When we first learned about entropy in Chemistry class, the teacher explained that entropy is like having a glass of water and dropping a sugar cube into it so that the sugar dissolves: you cannot reverse that process.

Then a student put his hand in the air and said that yes, of course you can reverse it. You evaporate the water and then condense it in a different container, then you take the sugar that is left behind and do whatever it is that you do to sugar to make it into a cube. You pour the condensed water back into the original glass, and now you've reversed the process.

The teacher was unable to counter this and just moved on after flustering a bit.

What he should have said is that the whole process of "reversing" the sugar dissolution which was described by the student requires tremendous energy input and that what he really should have said in the first place is that entropy is like dissolving the sugar and that you cannot reverse that process except by expending further energy to do so. (Which in the case of entropy just creates even more entropy, or in the sugar analogy which breaks down at this point you would need to dissolve 10 more sugar cubes elsewhere in order to un-dissolve the first one.)

Entropy is a tricky subject and trying to explain it to someone who has never heard of it is generally futile (except if they're actively trying to learn). A lay person can mix two reactive chemicals together, observe there is heat production without any other inputs, and conclude that entropy is bull because he just created energy (understanding that the chemicals also lost that energy is often one step too far). Or he can point out that photosynthesis produces energy-rich materials in defiance of entropy, completely overlooking the fact that his closed system will need to include the sun when doing that entropy analysis.

A statement such as "I think once the milestone of producing Hydrogen with less electricity than the energy density of the resulting Hydrogen is achieved, we will be there" can certainly be correct, but then only if you're also expending something other than electricity to create the hydrogen. What is this other energy source? (Ignoring the terminology clash here – it's not clear how you can directly compare "electricity" with "energy density of … hydrogen". What are your units for those? I am sure it is possible to define the terms such that the statement becomes universally correct, but I suspect it would also become trivially useless at the same time.)

Maybe energy density of the resulting Hydrogen fuel cell system is achieved...?

Hydrogen alone is pretty much like gasoline alone: gas theoretical energy density is enormous, but if you count all the parts needed to actually get that energy out (using ICE) it's no longer very high.

...that doesn't make sense either. Need to replace that "density" from there: energy output of the resulting Hydrogen fuel cell system is achieved...

My thinking was that the statement actually intended was something along the lines of "once you can recover more useful (possibly electric?) energy from the hydrogen than the electric energy that you needed to expend to manufacture that hydrogen then …"

Which is only possible if you have some additional energy input other than electricity. One plausible way of doing it may be to generate hydrogen from petroleum or natural gas both of which come with substantial useful energy already stored in their molecular structures.

Huh-oh... geek argument. Just what I was hoping to avoid.

frmercado: A tank FILLED with hydrogen is actually LIGHTER than when it empty...

Adding material to a container will always increase the total mass, obviously, and this matters in a vehicle. I think what you meant to say is that replacing a volume of air with a volume of hydrogen will reduce the weight of that object, which is irrelevant in the case of fool cells since the hydrogen, you would except, is compressed significantly more than the atmospheric pressure since the energy density per volume would otherwise be too low.

I like batteries because in theory they don't lead to this kind of pointless argument.

@bent, thank you for explaining entropy to everyone here, you certainly have made it clearer than I could ever have hoped for.

@ TeslaRocks

I most concede that my posts have been vague, but I don't have time to go over every single detail and prove it with math every single time I post something here, I do have a job. Still, I have posted several links with the math proving my assertions, and although electricity is used in electrolysis, the laws of thermodynamics only apply to that single process, but you cannot talk about a perpetual motion machine because there is no energy released or produced from that process, just a by product, Hydrogen, which is the fuel itself. You could make an analogy to mining; how much energy does it take to mine a certain raw material and how much energy does that raw material has the potential to generate? If you spent as much energy to mine it as the resulting energy that the material will produce it obviously doesn't make any sense. In this case the hydrogen separation method is the "mining" there are several ways to do this; electrolysis is the oldest and simplest, but also the most energy intensive, there are other ways to separate Hydrogen not only from water but from all sorts of molecules to which it is attached, remember that H is the most abundant element in the Universe, its caveat is that its always comes attached to another molecule, otherwise it would just fly into space. there is a lot R&D involved in making this process better and more efficient; just like in solar energy where the Holy Grail is a 50%percent efficiency from photovoltaic cells, the threshold whereas a Hydrogen economy would become viable is 10%, right now we are 5.3. Like I said right from the beginning there is still a long way to go but a H economy is certainly viable, otherwise companies like Toyota wouldn’t be betting on it, I’m sure they’ve done their research. I do think though that EV’s are the way to go right now, but who knows in 20 years?

@ Timo
Yeah, if you fill a tank with non compressed hydrogen (gas) it will be lighter, just as if you feel a balloon or a zeppelin, which would all gain mass but still weight less than the surrounding air; it will obviously WEIGHT MORE if the hydrogen is COMPRESSED. My bad, for the misrepresentation, I was just trying to make a point on how light it is in terms of weight/energy compared to anything else out there. But this takes me to following point, the energy density of hydrogen is so high that a few kilograms of compressed hydrogen would equal the more than half a ton of battery needed to store the same amount of energy. Also, I don’t think any modern tank would let escape any hydrogen throughout any period of time.

@frmercado, it's not the hydrogen weight or its theoretical energy density that is questionable here, it is the whole system. You need those tanks which are not weightless and HFC to make anything out of it. Tanks are quite large and total size of the HFC is not small either. It is same with gasoline, its theoretical energy density is also a lot higher than batteries, but it doesn't really win by much (if at all) when you count total weight and size of the entire system compared to output energy and power.

Hydrogen works better for houses than cars because volume doesn't matter that much and FC can also be a lot smaller (very few houses use over hundred kW at any given moment).

Hydrogen goes right thru pretty much any material. It does that quite slowly, but it does that. As you pointed out single hydrogen atom consist of one proton and one electron. That atom size is so small that it goes thru gaps of other material molecules. If the hydrogen atom loses its electron result is single proton. For that any material is basically just empty space.


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