Questions about a Hydrogen Economy; Scientific American

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The discussion centers on the concept of a "hydrogen economy," highlighting the misconception that hydrogen serves as a direct energy source like fossil fuels. Participants emphasize that hydrogen production requires more energy than it yields, often relying on fossil fuels or coal, which raises environmental concerns. The potential for nuclear energy to contribute to cleaner hydrogen production is noted as a preferable alternative. There is a consensus that while hydrogen can be an energy carrier, significant advancements in production technology and infrastructure are necessary for it to be a viable solution. Overall, the dialogue reflects skepticism about the feasibility of transitioning to a hydrogen economy without addressing underlying energy production challenges.
  • #331
There are many reasons to remove carbon from the fuel chain. Yes, pollution is one reason, but greenhouse gas emissions are the primary concern.

If scientists magically declared an end to our global warming concerns, I would jump off of the hydrogen-only bandwagon in about five seconds.
 
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  • #332
Various definition of pollution

Ivan Seeking said:
pollution is one reason, but greenhouse gas emissions are the primary concern.
Sometimes greenhouse gas emissions are referred to as "pollution."
http://www.google.com/search?q=greenhouse+gas+pollution

Do you know what equivocation is?



If scientists magically declared an end to our global warming concerns, I would jump off of the hydrogen-only bandwagon in about five seconds.
Perhaps global warming and its causes and social impacts should be addressed in another thread in another section of Physics Forums such as Earth and/or Social Sciences.
 
  • #333
hitssquad said:
Sometimes greenhouse gas emissions are referred to as "pollution."
http://www.google.com/search?q=greenhouse+gas+pollution

Do you know what equivocation is?

What is your point? You used the words noxious and smog-forming pollution, neither of which apply to CO2 within the context of global warming.


Perhaps global warming and its causes and social impacts should be addressed in another thread in another section of Physics Forums such as Earth and/or Social Sciences.

The source article for this thread discusses greenhouse gases in fair detail. So it is completely on topic as far as technology options and motivations are concerned.
 
  • #334
Ivan Seeking said:
What is your point?
Pollution can mean -- and often is used to mean -- various different things. When a speaker specifies what he is referring to by his use of an equivocal term such as pollution, there is less confusion. Use of equivocal terms without differentiation is equivocation and is confusing. Lack of confusion is important for scientific communication. Arthur Jensen reports that elite scientists tend to be earnest about minimizing confusion in communication.



You used the words noxious and smog-forming pollution
That differentiates quite well from other forms of pollution, yes?.



neither of which apply to CO2 within the context of global warming.
Yes. That is very clear, isn't it?
 
  • #335
I made my meaning clear when I said greenhouse gases and CO2. If you have a point please make it.
 
  • #336
H2R Liquid Hydrogen powered BMW: Top Speed over 300 km/h

BMW Writes Automobile History and underlines Technological Leadership.

Hydrogen means top performance not only in rockets traveling to outer space:

...Indeed, the specifications of the H2R Record Car clearly confirm this superiority, the six-litre 12 cylinder power unit developing an output of more than 210 kW or 285 bhp. This accelerates the BMW prototype to 100 km/h in approximately 6 seconds and gives it a top speed of 302,4 km/h (185,52 mph). Based on the gasoline power unit featured in the BMW 760i, BMW's hydrogen combustion engine boasts the most advanced technologies such as BMW's fully variable VALVETRONIC valve drive. [continued]
http://www.germancarfans.com/news.cfm/NewsID/2040920.001/bmw/1.html

Edit: Note that this car can run on gasoline or liquid hydrogen with the flick of a switch. Also, according to one interview on Discoveries This Week, over the next few years, BMW expects there to be enough H2 fueling stations built in Germany to justify production of H2 powered cars. I don't know who's buying the hydrgoen now or what motivate the installation of these stations, but it sounds like Germany is hot on H2.
 
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  • #337
The most significant differences in terms of the engine's structural components are the hydrogen injection valve and the choice of materials for the combustion chambers: Contrary to the production engine with fuel injected directly into the combustion chambers themselves, the injection valves in the hydrogen engine are integrated in the intake manifolds. And for the specific speed record requirements to be fulfilled in this case, the hydrogen combustion engine was designed and built for single-mode operation running exclusively on hydrogen.
the test car can not switch between gasoline & hydrogen :bugeye:
 
  • #338
Sierra Nevada Brews Up Environmentally Friendly Fuel Cell

...Designed to create energy without combustion, the 1 MW power plant consists of four 250-kilowatt Direct FuelCell(R) (DFC(R)) power plants from FuelCell Energy, Inc. (NasdaqNM:FCEL). Its waste heat will be harvested in the form of steam and used for the brewing process as well as other heating needs. One MW of electricity (equivalent to the power needed to support approximately 500-1000 homes for a year) will supply essentially 100 percent of the brewery's base load power requirements. With this power plant, Sierra Nevada not only lowers its overall energy costs but also eliminates air pollutant emissions equivalent to removing 500 gasoline-powered cars from the road every year. When the fuel cells generate more power than the brewery requires, Sierra Nevada sends excess electricity back to the grid system and receives credit for a portion of its generation costs. [continued]
http://www.rednova.com/news/science/190024/sierra_nevada_brews_up_environmentally_friendly_fuel_cell_electricity_gov/
and
http://www.alliancepower.com/sierra.html
 
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  • #339
Promising?

This looks like a promising approach to hydrogen delivery. It still has development issues but they look solvable. What do you think?

KM
 
  • #340
SPECIAL REPORT: Thinking Beyond Oil

AS THE PRICE OF A BARREL OF OIL continues to surge and oil traders eye possible disruptions in production from hurricane Katrina, scientists are turning to the ocean as a possible source of alternative energy.

Many forms of renewable energy have been contemplated, and of course solar and wind power plants are already in use. But so far, only a small fraction of the world's energy production comes from renewable resources.

President George W. Bush has talked of a hydrogen economy, in which abundant energy would be extracted from water and the tailpipes of cars would be clean. But extracting hydrogen from water requires energy -- fossil fuels or nuclear power, for example. Many scientists say technology will never allow the extraction of a enough hydrogen to make up for the energy needed to do the extracting. ]continued]
http://www.livescience.com/technology/ap_050826_wave_energy.html
 
  • #341
Ivan Seeking said:
http://www.livescience.com/technology/ap_050826_wave_energy.html
"There's a real good chance that Oregon could turn into kind of the focal point in the United States for wave energy development and I think that would be a boon to the economy,'' said Gary Cockrum, spokesman for the Central Lincoln People's Utility District."

Everyone wants a research grant, Ivan.
 
  • #342
Thanks for the great insight. :rolleyes:
 
  • #343
"Plug in your laptop to a cool hydrogen power source"

If you can't bear to be away from your laptop during that camping trip to deepest Borneo, help may soon be at hand. Lightweight generators powered by methanol are now on the market... for the rich, at least.

The device, designed to specifications for the US Army by the California company UltraCell, weighs just 1.3 kilograms when fuelled up and is the size of a novel. With a supply of 500 millilitres of methanol, the cell can chuck out 45 watts for a day, which is enough to power a laptop.

The cell and fuel together are half the weight of the lithium batteries needed to provide the same power.

Unlike traditional generators, fuel cells are totally quiet. And unlike batteries, they can be 'recharged' without being plugged into the wall. [continued]
http://www.nature.com/news/2005/050822/full/050822-8.html
 
  • #344
Ivan Seeking said:
http://www.livescience.com/technology/ap_050826_wave_energy.html
No offense Ivan, but when I see statements like these:
...in which abundant energy would be extracted from water... [uh, energy is not extracted from water]
and
Many scientists say technology will never allow the extraction of a enough hydrogen to make up for the energy needed to do the extracting. [but only those who understand the first law of thermodynamics :rolleyes: ]
...I cringe. Its articles like that, where the writer misunderstands the 1st law of thermodynamics (and pretty much everything else about the subject she's writing about), that make people have unrealistic expectations of what hydrogen can do. Much of the rest of the article is a bunch of second-hand soundbytes of similar uselessness. Ie:
"I read something involved with this that said if 0.2 percent of the ocean's energy were harnessed, it could produce enough energy to power the entire world,'' added Cockrum, the utility district spokesman. [emphasis added]
"I read something..."? A reporter actually put that quote into an article? Jeez, did she take journalism 101? Terrible, terrible article.

The biggest difficulty facing us in the so-called energy crisis is bad information coming from government and the media, making people think wrong things about our energy situation. Ie, the nuclear power decline caused by misinformation following TMI.
 
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  • #345
russ_watters said:
...where the writer misunderstands the 1st law of thermodynamics (and pretty much everything else about the subject she's writing about)...
Holy crap, the writer is an electrical engineer?? What the...?
 
  • #346
russ_watters said:
No offense Ivan, but when I see statements like these: and ...I cringe.

What exactly is your objection? If the energy is not in the water ala wave energy then where is it? And you seem to be objecting to the notion that we need need energy to "extract" hydrogen. I mean, I don't have any vested interest in livescience, but the meaning seemed pretty clear to me. Maybe you misunderstood.
 
  • #347
Okay, I think you are reading this wrong. You were thinking the article is about extracting H2 from water for energy?
 
  • #348
Actually, I think he's reading it right, if he's talking about this segment:

President George W. Bush has talked of a hydrogen economy, in which abundant energy would be extracted from water and the tailpipes of cars would be clean. But extracting hydrogen from water requires energy -- fossil fuels or nuclear power, for example.

which is definitely talking about extracting hydrogen from water. And the other statement,

Many scientists say technology will never allow the extraction of a enough hydrogen to make up for the energy needed to do the extracting.

seems a bit silly to me,as well. "Many scientists say"? No, the law of entropy, arguably the most verified and inescapable truth of the physical universe, says. This isn't a question of "...technology will never allow...", but the physical laws of reality will never allow.

I am somewhat hopefull that the new breakthrough in carbon nanotubes will at least partially solve some of the most outsanding storage problems.
 
  • #349
Well, according to the article in the OP, it's not so clear cut since the complete well-to-wheels efficiency of the system has to be considered. For example, it is more efficient to crack the hydrogen in methane and run that H2 in a Hydrogen fuel cell, than it is to run methane directly in methane fuel cells.

In either case, this article is about using ocean wave energy and the continued talk of the Oregon coast being a great focal point for this effort. The logical connection to H2 is that wave motion energy probably lends itself well to producing [cracking] H2. If I were an engineer wanting to work in this industry, I would sure want to know about the work in Oregon.

Not to mention that I am, I do, I'm here, so I hope to. :biggrin:
 
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  • #350
btw, I have worked with Prof von Jouanne, and not only is she is a class act [having helped me to get my business going in the very early days], she is also very, very smart. She did a lot of work that help to solve the problem with VFD induced motor failures, and she allowed me to use some of her work [equations] to solve some problems that I had with a related technology. But in any event, I would chalk up any misstatements to LiveScience; or perhaps nerves.
 
  • #351
President George W. Bush has talked of a hydrogen economy, in which abundant energy would be extracted from water and the tailpipes of cars would be clean. But extracting hydrogen from water requires energy -- fossil fuels or nuclear power, for example.
How much hydrogen could be produced by a Large (1MW) wind turbine in a year??
 
  • #352
One can find some information here.

Hydrogen Fuel Cells and Infrastructure Technology.
http://www.eere.energy.gov/hydrogenandfuelcells/analysis/cost.html

Technological Feasibility and Cost Analysis
http://www.nrel.gov/docs/fy04osti/36734.pdf

Based on 3.1557 E7 sec/yr and 1 E6 J/s = 3.1557 E13 J/yr (for 1 MW windmill),

and simply using heat of formation of water - 285.83 kJ/mol,

then one obtains about 1.1E8 gmoles of H2 or 2.2 E8 g/H2 per year, but that assumes 100% efficiency.

For some bascis on electrolysis and fuel cells, see - http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/electrol.html#c1

The numbers from DOE's Energy Efficiency and Renewable Energy (EERE) are more realistic.
 
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  • #353
220,000 kg of hydrogen from one wind turbine , thanks.. :smile:
 
  • #354
willib said:
220,000 kg of hydrogen from one wind turbine , thanks.. :smile:
It will most likely be less than that depending on the efficiency of the electrolytic cell. I assumed ideal conditions, not accounting for recombination and other effects.

The EERE reports should give better information.
 
  • #355
Astronuc said:
It will most likely be less than that depending on the efficiency of the electrolytic cell. I assumed ideal conditions, not accounting for recombination and other effects.

The EERE reports should give better information.
i understand , i was looking for a ballpark figure.. :smile:
Thats a lot of Hydrogen , no ?
 
  • #356
The chicken and egg problem

Note that there may be partial solutions to two key challenges to a hydrogen economy.

First of all, biofuels from algae appears to offer an efficient and practical solution to solar energy conversion. In effect, by farming algae for the production of biofuels, one grows the solar collector. Test crops have produced the fuel equivalent of about 925KW-Hrs per acre-day. Also, whereas alternate sources of biodiesel feedstock typically result in a return on invested energy of a little more than 300%, algae developers are claiming returns of up to 1000%.

Next, it occurs to me that the use of algae for biofuels - in particular, for biodiesel - offers a partial solution to what is known as the "chicken and egg problem" of a hydrogen economy. Since algae can be farmed for the production of biodiesel, an immediate economic justification and motive to farm algae exists. This is presently an infant industry. The biodiesel industry itself is growing quickly with many sources of feedstock including used cooking oil, and raw canola, soybean, palm, and rapeseed oil, to name a few.

As demand for hydrogen comes into play, since algae can be used to produce biodiesel, ethanol, or hydrogen, algae farms geered towards biodiesel production could likely convert to an algae that is well suited for hydrogen production. Much of the farming and processing requirements remain a constant.

In effect, we may have our source of hydrogen as well as a transition technology.
 
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  • #357
You read my mind, Ivan. That is exactly the series of events I'm hoping to see happen. (I'm currently attending college with an eye towards working in the "alternative fools" industry.)
 
  • #358
Cool! :approve:

I hope to be knee deep in pond scum in a couple of years.

The yeild per acre per day for farmed algae is mind boggling. Even with a three-acre test plot, I should expect a little less than a ton of dry algae per day. [eh, more like 1300 Lbs]. This then should yield no less than 40% as much oil.
 
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  • #359
Just caught this in the news.

BMW is the only major carmaker to bring a car with a hydrogen-combustion engine beyond the prototype stage.

The automaker's approach is markedly different than the more familiar concept of hydrogen-powered fuel cells, where energy is stored before it is converted into electricity. By contrast, BMW's Hydrogen 7 is powered by pumping hydrogen into a combustion engine and igniting it. The engine can burn both hydrogen and gasoline, and switches between the two at the flick of a switch.

Burning hydrogen is more efficient than converting it into electricity, making it the more practical choice for hydrogen-fueled cars now, according to BMW.[continued]
http://www.wired.com/news/technology/autotech/0,72100-0.html?tw=wn_index_1
 
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  • #360
Burning hydrogen is more efficient than converting it into electricity, making it the more practical choice for hydrogen-fueled cars now, according to BMW

I'm prety sure they're just flat-out wrong about that one. Fuel cells are much more efficient than internal combustion.
 

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