Hydrogen as energy carrier

[skravlinge]

As you do not find hydrogen which is in free gas anywhere, to a large amount, it has to be produced, using energy. So hydrogen is mainly a storing medium for energy. If the hydrogen should be used in a "green" way, it can not just be extracted from petrol or natural gas(even if they try to hide the CO2 in the ground, there are limit of the  resource). On Iceland there they have energy from the underground, hydrogen can be produced to a amount to make the hole country running on hydrogen. They are about 300000 people, and short transport so how are the billions other doing?  Solar can be used for hydrogen production, but it needs a complete new infrastructure, and I think its easier and cheaper to produce heat and electric power instead, such plants can be small or big and give better return. To extract hydrogen from corps, will be possible and "green", but will it pay? Is it not more easy to use  a simular infrastructure we have today, and basic the same  engines and run them on alcohol or biodiesel? It is a risk that a hydrogen society will looks at the fossil society today, with the power of the power belonging to a small number of big companies.

That one who grows a energy corp, will benefit more producing in small scale for own and local use, than sell all to the big company. Making ethanol or biodiesel is suitable for a number of smaller  business. There might be bigger plants, maybe offshore, using waves, wind, solar or temperature difference in the oceans, there hydrogen can be the best, but then we are talking of operations of the big.

Transport of hydrogen to a plant consuming a lot, is not a big problem, but build a infrastructure to make it for almost every energy need, I think will be more complicated than other options. With windpower its possible to make hydrogen in smaller scale, but I doubt it will be common, and often then for the producers own use. In discussions of hydrogen, I have seen so many times the fact that hydrogen is not a resource like oil or wood, it has to be produced are complete  left aside.

[stop4stuff]

The following figures aren't 100% accurate... near enough tho (iirc)... someone correct the math if needs be.

Say solar energy = 1kw per sq. meter.

A solar panel around 10-15% efficient at converting the sunlight to electricity.

Using the generous end of conversion (15%) 1kw now becomes 150w.

Say, an electrolyser can be made to be 70% efficient at producing hydrogen (+oxygen)... 70% x 2/3 = 46.6% (2/3 because you only want to collect the H from H2O)

Now 150w becomes 69.9w... 69.9/1000 x 100/1 = 6.99% efficiency.

So using sunlight and solar panels, around 93% of the sun's energy is wasted in producing hydrogen. Just about all of the wasted energy is lost as heat.

And that is before you even take into consideration the energy cost in producing storage facilities or safety aspects.

What happens to the hydrogen once you have made it?

ICE = 30 - 40% efficiency...

That 1kw now becomes the eqivalent of 27.96w (about 1/27 hp) of useable mechanical force from 1 sq m of sunlight.

Or 1kw of stored electricity becomes the equivalent of ~186w (around 1/4 hp) of useable mechanical force (add in you own efficiencies for creating the electricity and storage medium)

Fuel cell... ? efficiency and ? cost (? cost of waste product processing!)

Consider a heat difference engine (does Iceland have alot of underground thermal sources?)...

around 25% efficient... equivalent of ~250w (~1/3hp) of useable mechanical force from a 1kw heat source (sunlight, waste heat...etc) and no direct waste products!

Consider bio-fuels.... 11,000 sq miles of land could produce enough bio-fuels for the whole of America's transportaion needs.

Search this site and the web...

Production, energy density and storage of a fuel are the big issues, hydrogen doesn't come anywhere near safer liquid bio-fuels... (or methane, coal/wood gas, etc...)

Hydrogen = hype!

(although hydrogen can be used to enhance the efficiency of an ICE running on other hydro-carbon based fuels whilst creating  hydrogen + oxygen at the same time)

Perhaps hydrogen hybrids may work?

[skravlinge]

Iceland is an exception, they can  and produce most of its energy from underground heat (hundreds of centigrades), It is  vulcanic islands just on top of the midatlantic, half  of Iceland move in direction of America and the other half in direction of Europe, by a few centimeters a year. Its has very vulcanic ground.

All heating of houses in the capital where near about all lives comes from underground sources. It is planned to locate alminuim plant there (its as today cheaper to transport the bauxit  than transport energy for it). They plan to invest much in hydrogen, mainly for industries with high demands of energy, as they can do it very cheap.

[TomW]

Hydrogen is mostly hype because any real use of it will involve OIL. Just tactics to keep the cash coming in.

And, as paul noted, the efficiency of hydrolyzing water is sad.

T

[stop4stuff]

If there is an abundancy of natural thermal energy... why waste it on inefficient hydrogen???

Haven't we learned about wasting natural resources with oil???

If Iceland becomes a huge heat difference engine, what will happen to the earth's core...

And what will happen to the polar ice  caps (and global sea levels) as that heat is released???

Or will that be the worry of future generations???

[skravlinge]

If no greenhouse gases are released, the excess heat from all energy use will go to space, as most of the solar heat do. They can never take out so much what the ground cools, even if it should make the life a bit safer, the ground is living.

[stop4stuff]

Solar thermal energy comes in during daylight hours and is released at night.

Underground thermal energy would be released 24/7 and never put back...

So why waste it in producing inefficient hydrogen???

[stop4stuff]

nuff sed (=enough said

[jimjjnn]

Well put TOM. Keep that bull around for the ou people too

[TomW]

Hey, if you like that you will love this:

[ghurd]

I have a fish tank doo-hicky that splits water into H and O2.  I think.  Thats what they claim.  It uses about 90ma at 12v (2 in series production version). Totally silent, no moving parts, looks like a little speaker.

It is an "Oxygenator".  It is made for fish, but finish reading if you want it for fish!

The H comes up in larger bubbles that pop at the surface.

The O2 is in tiny bubbles that can't break the surface tension, so they stay in the water until they are disolved. You can see them though, it looks almost like smoke in the water.

The idea is that H leaves, and O2 stays for the fish.

The bubbles at the surface do burn!  So I think it works for the water spliting.

This could, maybe, be a setup for experimenters to get some H. I think it could just be collected with a submerged funnel.

Makes a bleach smell.  Anyone know why?

DISCLAIMER

DO NOT  use it for fish!!!

No matter how good it sounds!

I used it for 10 hours over night.  There was a huge smell of Clorox or bleach, and I mean more than like an open gallon of bleach. Disconnected it right then. 40% of the fish were dead, and continued to die slowly for another 2 days. About half survived. I figured this one was bad, and tried another one, but without the fish. Same strong bleach smell.

People on the web love these things for bait minnows for days on end.  Could I have gotten 2 bad ones?  I don't know, but at $100 EACH, I'm not going for a third try!

I let the water sit for 4 weeks before starting the second try.

I let the unit sit for 2 months before starting (just in case it was un cured potting compound or something), then washed it 2 times a day for maybe a week.

The company is always going to call me back soon, when the right guy is 'in'. He has been 'out' for over a year now.

I'm not using these, so if someone wants to kill some fish, I'll let them go for half price!  The 2 'speaker', 12v type.

Can someone explain the bleach smell?

G-

[RP]

Ghurd,

By any chance are these SALT water fish?  If so, the device may have been breaking down the salt in the water to form sodium  and chlorine.  The sodium would've combined with the water to form sodium hydroxide (nasty for fish but good for cleaning drains) and chlorine gas which would dissolve in the water and give a strong smell of bleach or pool water (also not good for fish).

rp

[ghurd]

Not salt water.

Actually, 3 tests with 'aged' city water from my house (standing open for a couple days) supplied by a lake and 2 with well water from wells about 3 miles appart, 40 miles from my supply lake.

To my knowledge, none of which has a high concentration of salts.

But yes.  The whole house smelled like the YMCA!  The indoor city swimming pool for those not familiar with the YMCA.

I wonder what the saline content has to be to get that?  Maybe there is enough in the water I used.  But I think the company web site said it works for both, and they use it for their salt water fish tanks (when I called about it) in the offices.

Been thinking about it for a year.

Thanks

G-

[tecker]

  That cow's gonna miss and then somebody is gona have to get the pooper scooper anyhow.by the time they get thier tail up it's commin out .

[jimjjnn]

Tom W, You better not leave this board ever.

Have to have humor as well as other good stuff. Keep up the good work and keeping us all sane

[JW]

Actually PopSci (magazine) Has an artical on the proposed Hydrogen Economy This Month. I read the artical today pg 64 or something like that. I thought it was a pretty decent write-up on fuelcells and such. The one thing that stuck with me the most, is that, to power a fleet of fuelcell powered vehicals, and replace what we currently use with fossel fuels, someone refered to in the write-up, would consume 3months worth of the water flowing over Niagra Falls for enough H2 production to supply a hydrogen fuelcell fleet of cars for one year. They also point out, that most likely H2 energy storage, will only be practical for windfarms that produce over a megawatt, most likely the vast sparse spread of home brewed wind turbine systems will use batterys as a means on energy storage.

JW

[DrHayt]

I am looking to be educated:

Lets ignore the initial source of the energy, its storage, and any

dangers for just a moment.

I am led to believe that PEM electrolyzers with palladium scrubbers

routinely achieve efficiencies greater than 85%.

Lets make the calculations simple:

1000w in equals 850w out.

Then you throw in a 2/3 (2 parts hydrogen, 1 part oxygen I assume, wondering

if this is actually how it works, isnt the hydrogen the storage medium and we

just sort of ignore the oxygen?)

so now 850w in equals 565w out (rounded handily down)

So now for every 1000watts I throw in, I have in hydrogen form about 500watts.

But then I have to turn that back into electrical power, so I use a fuel cell

to do that.

Suppose that the efficiency of the small scale PEM fuel cell I have is

50. %.  Doesnt this mean that:
    
500. watts in equals 250watts out?
     
     

So that means that the overall efficiency of the whole loop is

25%.

What am I missing?

Thanks!

DrHayt

[p0lizei]

City water is chlorinated, so you're still giving off chlorine gas.  I'll have days where I draw a bath or fill the sink with water and it smells like a pool.  And they expect me to drink that crap?

[kurt]

cool pics tom

 check out my latest acquisition

[stop4stuff]

If you're using electricity for electrolysis, where does the electricity come from?

And why not use a >90% efficiency electric motor for whatever puprpose the hydrogen would be put to?

[skravlinge]

The thermal energy will go to space soon or later, if not  24/7.  Geyiser as you find in Yellowstone for example is an Icelandic world and they have a lot.The underground heat  has a temperature which can run a steamturbinne straight away. Its not possible to export the power as electricy, its has to have a carrier.

The only option seems to be hydrogen. You can calculate a loss with figures up to 60%. But is the cost of a KW is  1.5 cents and hydrogen is the tightest and lightest energy carrier, it can in this case  be the only sensibele way to do it.

Using hydrogen from other sources than thermal energy may be wast. If you can use the electric power on the place or the grid connected to it. I think the market for thermal processed hydrogen will be to large industries using a lot of energy, like metal processing. An ordinary alminium plant use power as a big city, and theire options are hydrogen, waterpower, nuke or fossils. The domnestic use of thermal energy  on Iceland is to straight use the hot water for heating and electric power. Other sources like biomass, wich is cheap to produce on latitudes below 57 N can be better used as biodiesel, ethanol than convert to hydrogen. It you got electric power, its better to use it as electric power than run through hydrogen. Its special case on Iceland.

[skravlinge]

I do not think the whole carf leet will ever use hydrogen, and if I am wrong the water will not be taken so it close  the Nigaria fall. The fuel for most of the cars will  have a bio origin in the future.  The prime source for the  hydrogen production, in America what would it be? Oil? not for cars, it can be used as it is. Waterpower? Its not so much on hand and build more will wast the land.

Biolmass? could be cheaper converted to fuel.  Nuke? produce danger and dangeros wast. Solar? maybe, but better to use  that part of production for electrc power. I can not see a prime energy for hydrogen on a mass production. The hydrogen will maybe come made of natural gas, there they try to fool they can hide the CO2 underground, but it will in this case not be for very long time, as the demand of energy goes up in the world, the price of gas will follow. I think it is a national security problem, not secure energy with starting farming biocorps to feed the carfleet, its probably cheaper than they think. You may not have to spend so much on the military then.

[skravlinge]

Thats right, but still its a matter of the prime energy, elctric power is a "carrier" like hydrogen, you do not find it, you need someway to produce it. So its a question how you get the prime source, their cost, if it is on hand, if it  creates danger.  The overall cost involved in energy, including handle, transport, and even politics, has to be counted. If all this  are taken in account, local production of  energy from sun, wind, corps or whatever RE  is on hand, is  cheaper than it looks.  It is not only the energy efficiency of the system which count, it is the economical , and security  problem as well.

[finnsawyer]

I think your 2/3 may be in error.  When the hydrogen burns all that has to be overcome energy wise is the bond energy in the H2 and O2, which is probably not much.  So you probably get back nearly all the energy that went into the H2.  I guess someone must have those figures.

[finnsawyer]

When they come up with a plant that doesn't need fertilizer or cultivation and that grows like crazy then I'll buy into the idea of producing fuels from crops.  Well wood's close, but too slow growing.

Some years ago I heard about a proposal to dam the mouth of Hudson Bay to produce electricity.  While this would have a possibly detrimental effect on marine and wild life as the bay changed to fresh water, it is technically feasible as the mouth of the bay is relatively shallow.  There are numerous rivers dumping into Hudson Bay, among them the Red River of North Dakota and the Water Hen of Manitoba.  Believe me a lot of water is flowing north to that bay.  I've seem both rivers.  So there are still available massive potential hydroelectric projects if we're willing to pay the environmental costs.

Basically, I'm still skeptical about the feasibility of fuel cells for everyday transportation.  Will they work at 20 bellow zero and how do you get fast start up, for instance?  What about life span?  Will the Partanen aluminum battery prove successful first.  

"Question everything!"

[finnsawyer]

Question:  If Iceland has been spreading out for millions of years, sitting as it does on the mid-Atlantic ridge, why is it still an island, rather than two islands separated by hundreds of miles?

"Question everything"

[skravlinge]

The fertilizer for energy corps can come back and circulate. You produce the gas or liquid fuel from carbonhydrogen stuff built by sunshine, the minerals can go back and be recycled.