New Catalyst for solar power

[The Man]

Take a look.


http://www.physlink.com/News/080801CobaltOxygenHydrogen.cfm

Inspired by the photosynthesis performed by plants, Nocera and Matthew Kanan, a postdoctoral fellow in Nocera's lab, have developed an unprecedented process that will allow the sun's energy to be used to split water into hydrogen and oxygen gases. Later, the oxygen and hydrogen may be recombined inside a fuel cell, creating carbon-free electricity to power your house or your electric car, day or night.

A more efficient method of storing solar energy?

Let me know what you think.

 

[Spud1k]

A more efficient method of storing solar energy?

Let me know what you think.

Last I checked, fuel cells are only about 50% efficient, so efficiency-wise, the benefits of this over an old fashioned lead-acid battery aren't immediately apparent to me. I suppose storage-wise, it'd be more convenient to store a large amount of energy in the form of a big bag of hydrogen rather than a godawful huge and heavy battery, so maybe that might be a selling point.

 

[RecoveringYuppy]

Anybody see where that article says what the benefit of this new catalyst actually is?

 

[Spud1k]

Anybody see where that article says what the benefit of this new catalyst actually is?

I don't think it did - the author seems to have a very tenuous grasp on the topic (the paragraph under 'Just the beginning' made me snigger). I did a bit of Googling and found something with a little more substance; apparently, the new catalyst is cheaper, easier and with fewer nasty chemicals than existing ones.

 

[Pantaz]

I keep waiting for all the HHO/water4gas proponents to jump on this research as "the solution".

 

[The Man]

The implied benefit wasn’t apparent to me either, if I am remembering correctly current photovoltaics are under 25% efficient (if that) but I may have missed some new developments. It seems that would be where the new developments are needed.

The author also often refers to photosynthesis in the article (which if I remember correctly is something like 99% efficient) and infers a comparison but never directly compares them.

Certainly less toxic storage is good, but I don't find myself getting the enthusiasm over this discovery that the author clearly intended, but then I am a skeptic.

 

[The Man]

I don't think it did - the author seems to have a very tenuous grasp on the topic (the paragraph under 'Just the beginning' made me snigger). I did a bit of Googling and found something with a little more substance; apparently, the new catalyst is cheaper, easier and with fewer nasty chemicals than existing ones.

Thanks for the link, Spud1k, it certainly gives more information.

"The hard part of getting water to split is not the hydrogen -- platinum as a catalyst works fine for the hydrogen. But platinum works very poorly for oxygen, making you use much more energy," said MIT chemistry professor Daniel Nocera. "What we have done is made a catalyst work for the oxygen part without any extra energy. In fact, with our catalyst almost 100 percent of the current used for electrolysis goes into making oxygen and hydrogen."

Well, it still does not give an efficiency comparison to other forms electrolysis. Combined with the 50% efficiency of fuel cells, I really don’t see any significant benefit over batteries (other then reduced toxicity). Also I doubt (but I am not sure) that the short term storage efficiency of modern batteries is anywhere near as bad as 50%.

 

[RecoveringYuppy]

The author also often refers to photosynthesis in the article (which if I remember correctly is something like 99% efficient) and infers a comparison but never directly compares them.

Uhh, no. The 99% efficiency of photosynthesis is a creationist canard. It's typically down in the single digit percentages.

 

[Horatius]

Thanks for the link, Spud1k, it certainly gives more information.

We briefly mentioned this fellow in another thread. Here's some more info on what looks to be his patent:

This looks like his patent.

Embodiments for the invention include a process for the production of hydrogen comprising a protic solution, a photocatalyst capable of a two-electron reduction of hydrogen ions; and a coproduct trap. The embodiment includes exposing the reaction medium to radiation capable of photoexciting the photocatalyst to produce hydrogen. The protic solution may comprise at least one of hydrohalic acid, a silane, and water, and the hydrohalic acid may be hydrochloric acid, hydrogen bromide, hydrogen fluoride or hydrogen iodide. The present application also describes novel transition metal compounds. Embodiments of the compounds include a compound comprising two transition metal atoms, wherein the transition metal atoms are in a two-electron mixed valence state and at least one transition metal is not rhodium; and at least one ligand capable of stabilizing the transition metal atom in a two-electron mixed valence state.

Patent number: 6863781

 

[shadron]

I keep waiting for all the HHO/water4gas proponents to jump on this research as "the solution".

I haven' seen that yet, but when I went to the page two of the three Google ads were about HHO schemes. Yay, Google.

 

[neutrino_cannon]

Last I checked, fuel cells are only about 50% efficient, so efficiency-wise, the benefits of this over an old fashioned lead-acid battery aren't immediately apparent to me.

Energy density. Energy density. Energy density.

The gravimetric energy density of hydrogen, even after accounting for the inefficiency of fuel cells, is about five hundred times better than for lead acid batteries.

 

[neutrino_cannon]

Well, it still does not give an efficiency comparison to other forms electrolysis. Combined with the 50% efficiency of fuel cells, I really don’t see any significant benefit over batteries (other then reduced toxicity). Also I doubt (but I am not sure) that the short term storage efficiency of modern batteries is anywhere near as bad as 50%.

Current electrolysis of water is on the order of 50%-70% as per wikipedia. When you start factoring in the efficiency of making the electricity it gets downright ugly.

 

[soylent]

Energy density. Energy density. Energy density.

The gravimetric energy density of hydrogen, even after accounting for the inefficiency of fuel cells, is about five hundred times better than for lead acid batteries.

The steel required to store compressed hydrogen at acceptable volumetric energy density is so godawful heavy that this is reduced to about 40 times as good as a lead acid battery, not counting the energy lost as heat when compressing hydrogen to several hundred atmospheres.

 

[davefoc]

This is a link to a story about a cal-tech scientist that has developed a process for photo electrolysis using chemistry inspired by photosynthesis.

http://sciencedude.freedomblogging....ist-shines-new-light-on-alternative-energies/

The article doesn't provide much information, but it might be more likely that something like this is viable than using inefficient photovoltaic cells to power an electrolysis to generate hydrogen.

Either process might not be worth the effort. Neither article seems to have enough information to make reasoned guesses about the viability of the respective technologies.

The article linked to in the OP IMO makes wildly exaggerated claims as to the importance of the discovery in the overall scheme of energy relate developments.

 

[Spud1k]

This is a link to a story about a cal-tech scientist that has developed a process for photo electrolysis using chemistry inspired by photosynthesis.

http://sciencedude.freedomblogging....ist-shines-new-light-on-alternative-energies/

The article doesn't provide much information, but it might be more likely that something like this is viable than using inefficient photovoltaic cells to power an electrolysis to generate hydrogen.

Either process might not be worth the effort. Neither article seems to have enough information to make reasoned guesses about the viability of the respective technologies.

The direct splitting of water has been a minor holy grail of solar power for a long time. While I'm sure this advance is probably important, it sounds like they're still a long way off producing something workable and like you say, the viability remains to be seen.

The article linked to in the OP IMO makes wildly exaggerated claims as to the importance of the discovery in the overall scheme of energy relate developments.

No kidding. It seems if anyone can put a 'renewable energy' or an 'inspired by nature' tag on something it makes it nothing short of revolutionary amongst certain science writers. As far as I can tell, all they did was invent an electrolysis system that is cheap, efficient and suitable for domestic use. While it may have its applications, I don't think the world's energy problems are solved just yet.

 

[neutrino_cannon]

The steel required to store compressed hydrogen at acceptable volumetric energy density is so godawful heavy that this is reduced to about 40 times as good as a lead acid battery,

good point; and I put it to you that gravimetric energy densities are largely unimportant in certain applications.

Makes dandy rocket fuel though.

not counting the energy lost as heat when compressing hydrogen to several hundred atmospheres.

Do you suppose it's more efficient to compress it or chill it?

 

[Cuddles]

It's hardly new or unprecedented. OK, so they've got a new method of electrolysis that seems to be easier and use less toxic materials than most current methods. Great. Why can't Physlink just make do with announcing that, instead of implying that electrolysis and hydrogen as energy storage have never been thought of before?

Current electrolysis of water is on the order of 50%-70% as per wikipedia. When you start factoring in the efficiency of making the electricity it gets downright ugly.

I know, we can make the electricity using the hydrogen produced from the electrolysis! It's foolproof!

 

[robinson]

It's hardly new or unprecedented. OK, so they've got a new method of electrolysis that seems to be easier and use less toxic materials than most current methods. Great. Why can't Physlink just make do with announcing that, instead of implying that electrolysis and hydrogen as energy storage have never been thought of before

I thought the same thing when I first read it. It is some sort of Global stupidity or something. Or maybe to pump an article. I have no idea, but it irks me to see something that dumb.

 

[neutrino_cannon]

I know, we can make the electricity using the hydrogen produced from the electrolysis! It's foolproof!

If we market it as "green," yeah, it may have a shot.

 

[The Man]

It's hardly new or unprecedented. OK, so they've got a new method of electrolysis that seems to be easier and use less toxic materials than most current methods. Great. Why can't Physlink just make do with announcing that, instead of implying that electrolysis and hydrogen as energy storage have never been thought of before?



I know, we can make the electricity using the hydrogen produced from the electrolysis! It's foolproof!

I thought the same thing when I first read it. It is some sort of Global stupidity or something. Or maybe to pump an article. I have no idea, but it irks me to see something that dumb.

Precisely my take on the article, Cuddles and robinson, given the current interest in alternative fuel sources and peoples general lack of understanding of the current limits and efficiencies of alternative fuel sources, the most effective alternative power right now is hype. Physlink is one of the regular news sources I check for new developments in physics and technology but it seems they are falling into the same alternative power hype as the rest of the media.


I would just like to thank everyone for their constructive and/or humorous (or constructively humorous) posts on this article.