Questions about a Hydrogen Economy; Scientific American

[Seafang]

From the Energy Research Center of The Netherlands
http://www.waterstof.org/20030725EHECO3-132.pdf

An interesting paper; which however dodges the question of where you get hydrogen from.

So long as we have natural gas (fossil fuel) we have no need for the hydrogen; the NG is a perfectly good fuel by itself, providing the energy of combustion of the hydrogen as well as the carbon, and whatever chemical binding energy might be available.
Extracting the hydrogen from the NG has to be an energy losing proposition, so why do it; and you either end up with the same CO2 as before or else a pile of soot to be dealt with. It is still a Ponzi scheme. The problem remains what soures of energy we will have after the fossil fuels age.

As to your citations of cliches by Michio Kaku and other eminents; I don't get the point.

 

[Ivan Seeking]

An interesting paper; which however dodges the question of where you get hydrogen from.

So long as we have natural gas (fossil fuel) we have no need for the hydrogen; the NG is a perfectly good fuel by itself, providing the energy of combustion of the hydrogen as well as the carbon, and whatever chemical binding energy might be available.
Extracting the hydrogen from the NG has to be an energy losing proposition, so why do it; and you either end up with the same CO2 as before or else a pile of soot to be dealt with. It is still a Ponzi scheme. The problem remains what soures of energy we will have after the fossil fuels age.

If you look at the original article that motivates this thread, you will see that after converting NG to H2, the well to wheels efficiency of H2 fuel cells, for example, is better than NG powered fuel cells. This includes producing the Hydrogen from NG. The "soot" to be disposed of is valuable, high grade carbon that can be sold, which adds even more economic efficiency to the process. As for sources, this question is the primary point of this thread. You might also review the promise of ocean hydrates. https://www.physicsforums.com/showthread.php?t=58374

As to your citations of cliches by Michio Kaku and other eminents; I don't get the point.

I think you do, which is why you chose to comment.

 

[shrumeo]

From the document


So even if anthropogenic sources are small compared to natural sources (and absorbtion), these sources may well account for all of the increase in the atmosphere of carbon dioxide.

I tend to agree.

If we think of the Earth as mostly a closed system (except for the stray meteorite) then you have to fix carbon as fast as you oxidize it if you want to keep the atmosphere with the same amount of CO2 (does it matter?)

Unless photosynthesis can catch up with the rate that we dig carbon out of the ground and put it into the atmosphere, then there will always be a net increase in CO2.

QUESTION: As far as water vapor polution, couldn't this be reduced a huge amount simply by running the exhaust pipe through some kind of heat disapater, thus turning it into liquid water? Then the water mostly would just off the road into dirt where it would be absorbed... or occasionally on hot days re-vaporize into regular precipiation anyway!

Yeah, you'd be adding to the local humidity. Maybe if we all start driving in the desert it won't be so arid anymore.
I don't know if this is even something to worry about.

Evident is a company btw..

http://www.evidenttech.com/applications/quantum-dot-solar-cells.php
really interresting stuff..
http://www.google.com/search?hl=en&lr=&q=quantum+dots+Infrared+solar+cells

Don't get any CdSe on you or in you!

That would be the main complaint with this technology.
You'd be painting you sweater with quite toxic stuff.

Also, I can't see these cells in anything but niche markets, mainly because of the way the quantum dots are produced and their toxicity.

I think though that the use of the HIGHLY toxic dimethyl cadmium as a precusor has been replaced by the use of cadmium oxide for large scale preps.

But, think of the stink over lead in paint and then realize you'd be painting everything with cadmium (which isn't quite as toxic as mercury).

There are ways around this, by coating the particles with something moire inert, but eventually and inevitably, the Cd and Se will both leach out to wreak their havoc.

Anyway, people won't stand for it (even if it won't hurt them).

 

[Ivan Seeking]

Oregon may lead future of wave energy

CORVALLIS, Ore. – Significant advances in university research and other studies in the past two years are pointing toward Oregon as the possible epicenter of wave energy development in the United States.
This may lead to a major initiative to expand a technology that is now in its engineering infancy, and tap the constant heave of the oceans for a new era of clean, affordable and renewable electrical power.

Electrical engineers at Oregon State University have pioneered the development of technologies to take advantage of wave power in ways that are reliable, maintainable and able to survive a hostile ocean environment. The OSU College of Engineering also has a host of other facilities that would make it an ideal site for more advanced research.

Last fall, the Electric Power Research Institute finished a study which concluded that a site off Reedsport, Ore., would be the optimal location in the entire nation to develop a wave energy test and demonstration facility. [continued]

http://www.eurekalert.org/pub_releases/2005-02/osu-oml020105.php

 

[ohwilleke]

Keep in mind that lots of industrial processes already generate water vapor, probably in greater volumes than cars operating on hydrogen would. For example, coal burned in power plants has a significant water contents that is converted to steam.

It is hard to see hydrogen fuel emmission being significant compared, for example to vaporization of water from the surfaces of oceans that make up 70% of the planet. Moreover, if water is the source of the water vapor, you could end up having a source and sink that balance out. There is no obvious reason that increased water emissions increase atmopheric carrying capacity for water vapor significantly.

 

[Seafang]

If you look at the original article that motivates this thread, you will see that after converting NG to H2, the well to wheels efficiency of H2 fuel cells, for example, is better than NG powered fuel cells. This includes producing the Hydrogen from NG. The "soot" to be disposed of is valuable, high grade carbon that can be sold, which adds even more economic efficiency to the process. As for sources, this question is the primary point of this thread. You might also review the promise of ocean hydrates. https://www.physicsforums.com/showthread.php?t=58374



I think you do, which is why you chose to comment.

Well Ivan, I am quite used to presenting my thoughts and beliefs in words, either spoken or written; so I would caution against INFERRING anything from anything I say or write. If I wanted to IMPLY anything, I would state it specifically; so when I said "I don't get the point", I MEAN EXACTLY THAT. (fancy that the caps lock came on by itself, and I didn't mean to shout).

Each of the persons you cited is eminent in his field as a scientist or engineer. None of them is eminent in the field of philosphy.

 

[Chronos]

Well Ivan, I am quite used to presenting my thoughts and beliefs in words, either spoken or written; so I would caution against INFERRING anything from anything I say or write. If I wanted to IMPLY anything, I would state it specifically; so when I said "I don't get the point", I MEAN EXACTLY THAT. (fancy that the caps lock came on by itself, and I didn't mean to shout).

Each of the persons you cited is eminent in his field as a scientist or engineer. None of them is eminent in the field of philosphy.

And you make arguments that make no sense. I agree with Ivan. By the way, what in the world does philosophy have to do with this discussion? I thought we were talking about science. I don't get your point either, assuming you even have one.

 

[Ivan Seeking]

"Ethanol has the potential to be an integral part of the emerging hydrogen economy. Its properties make it an excellent liquid fuel for the extraction of hydrogen."
October 29, 2004
Des Plaines, Illinois [RenewableEnergyAccess.com]

Ethanol is commonly touted as an alternative fuel suitable for any vehicle. Researchers from the Gas Technology Institute (GTI) have produced hydrogen from the corn-based product, however, and that could shift ethanol into a whole new fuel market.

For the past six months GTI engineers have done research to demonstrate the potential of its fuel processor technology that is used to generate hydrogen from a variety of renewable fuels. A steam powered two-step, reforming-shift fuel processor is used for the conversion.

"We believe GTI is now strongly positioned to develop and deploy both stationary and transportation energy systems utilizing ethanol to hydrogen reformation," said Gerry Runte, who is the executive director of GTI's Hydrogen Systems Center. "We were able to produce a high-quality hydrogen gas from ethanol, similar to results using natural gas, and demonstrated our process to representatives of the Renewable Fuels Association (RFA)."

GTI is also developing a fueling station platform for a natural gas to hydrogen fueling station, and the institute would like to create an ethanol to hydrogen station based off of the same plans. Researchers are also pursuing the use of ethanol for stationary fuel cell demonstrations.

"Ethanol has the potential to be an integral part of the emerging hydrogen economy. Its properties make it an excellent liquid fuel for the extraction of hydrogen," said Runte.

The institute has over three decades of experience in converting a variety of fuels into hydrogen, according to the company press release. They use an optional passive carbon monoxide (CO) control system that consistently produces less than 4 ppm CO without requiring complicated control systems. The unit is adaptable to use either fuel cell anode recycle gas or pressure swing adsorption off-gas recovery for efficient supplemental heat generation.

http://www.maui-tomorrow.org/issuespages/energy/ethanol_hydrogen.html

 

[ohwilleke]

Ethanol is probably more practical in the short to medium term as a liquid fuel replacement than as a hydrogen replacement. The biggest problem with ethanol is that even using a large portion of the entire agricultural output of the United States you are making only a modest dent in U.S. oil consumption.

Ethanol may ultimate be the primary liquid hydrocarbon fuel when oil supplies grow very expense to tap. But, it is not a good total solution.

 

[Ivan Seeking]

I think a key concept in all of this is diversification. The beauty of using H2 as the base energy carrier is that it allows for a standardized fuel that has many, many sources. I would expect that any number of competitive methods for H2 production will emerge. Some will be based on existing hydrocarbons sources such as ocean hydrates and natural gas, coal, ethanol and the like, and others will come from biomass consumption and other bacterial processes. I suspect that wind to H2 through water will prove viable in wind friendly areas, solar to H2 will be used in solar friendly areas. Even nuclear energy may be used to make the stuff. Also, as the economic benefits of a hydrogen economy become clear, industry will find many ways to produce H2 for resale as as byproduct of existing processes.

If one reviews the first page of this thread and the many links throughout, one will see that dozens of promising methods are explored for H2 production.

 

[Seafang]

A review of the links given in the Hydrogen thread addresses the many methods explored for producing H2.

Russ, I think your concerns are completely valid. You and I have already hashed this out pretty well in the thread linked and I realize that we disagree on questions of production. I will only say that this is a core issue being addressed on many fronts, and that many scientists feel that this is not a show stopper; but that much work is still needed.

By no means is this a done deal. To "Go Hydrogen" could still mean many different things depending on how the technologies pan out.

Finally, I make no bones about my motives here. I think we need many brains filled with thoughts of Hydrogen. Politically, economically, scientifically, and environmentally, H2 strikes me as our best hope to finally end our addiction to oil. The political motivation is now more obvious than ever. Bye bye OPEC!

Well so we get off our addiction to oil, and we make hydrogen; well the natural critters make it for us out of sunlight. So what Hydorgen ore do you suggest they use.

Is it Water? Tell us how many hydrogen production technologies (of the natural non man made kind) start of with water as the hydrogen ore. Is it a number greater than zero. I'll bet that most if not all don't start with water; they start with some sort of hydrocarbon, and we immediately remove coal oil and natural gas from the list no fossil fuels allowed remember. that leaves probably some plant materials; bu they are still hydrocarbons; ethanol is a hydrocarbon.

SO WHA T DO WE DO WITH ALL THE SOOT.

 

[Ivan Seeking]

Those are not only silly questions, they are also already answered in the many links provided. Read and learn.

 

[Ivan Seeking]

SO WHA T DO WE DO WITH ALL THE SOOT.

And I already answered this.

The "soot" to be disposed of is valuable high grade carbon that can be sold

Right now much of it goes into the air as carbon monoxide and dioxide. Much better.

 

[Chronos]

Perhaps a cowpie economy is worth exploring. Judging by this thread, it appears to be a renewable energy source.

 

[Ivan Seeking]

Could you elaborate a bit?

 

[Ivan Seeking]

Hydrogen-powered bike is too quiet

It can reach 50mph in 12 seconds, produces no emissions and is as quiet as a laptop computer - but that could be a problem.

...But engineers are considering adding an artificial "vroom" as they were worried its silence might be dangerous. [cpntinued]

http://www.ananova.com/news/story/sm_1321345.html?menu=

Some engineers were talking about this issue of sound on the recent SA Frontiers special about Hydrogen. One person mentioned that electric cars will be very boring as race cars. It is hard to imagine a field of nearly silent Grand Prix cars gearing down for the hairpin turn.

 

[hitssquad]

One person mentioned that electric cars will be very boring as race cars.

Why might race cars run on electricity instead of gasoline?

 

[Ivan Seeking]

Have you seen the T-Zero? http://www.acpropulsion.com/tzero_pages/tzero_home.htm

Already we have an electric car that outperforms most high performance autos. Also, IIRC, the advanced concepts engineers at GM were interviewed and I am citing their expectations.

I am pretty sure that the show can be watched online...in fact there should be a link in this thread. edit: Also, I am pretty sure that the prototype could do 0-60 in 3.0 seconds. The production car is claiming 4.1 seconds.

 

[Ivan Seeking]

This is it.
http://www.pbs.org/saf/1403/

 

[Chronos]

I agree with Ivan. Viable alternatives to hydrocarbon energy sources are well inside the radar screen. Already the nuclear option has become politically viable. I predict at least 50% of new energy production in the US will be fission based by the end of this century - nuclear power will come back with a vengeance. The advantages, particularly given technological advances, are too attractive to ignore any longer. Engineers will once again save the day! If it's any reassurance, the fate of humanity lies in people like me... plays spooky music

 

[Ivan Seeking]

Hah! A nuclear fan.
What convinces you that we can operate nuclear plants safely. That is to say, what new nuclear energy technologies make this a viable approach?

 

[hitssquad]

Viable alternatives to hydrocarbon energy sources are well inside the radar screen.

Features vs. benefits. What was questioned was not the existence of alternatives to hydrocarbons. What was questioned was the benefit of switching.

 

[hitssquad]

Have you seen the T-Zero?

The T-Zero runs on chemical energy cell batteries, not on fuel cells. Are you talking about race cars running on batteries or fuel cells? Do you know what specific energy and specific power are? Do you know how much energy is in a typical gallon of gasoline? Do you know what the efficiency of conversion of fuel cells currently is and what it is expected to eventually be?

 

[Ivan Seeking]

I repeated the quote about electric cars. I never said anything about fuel cells.

Edit: oh yes, yes, yes, and yes. Get a grip.

 

[hitssquad]

The motorcycle you linked to runs on a fuel cell. Do you think on-road electric vehicles might run better on batteries, fuel cells or something else? What might electric race cars run better on?

 

[Chronos]

Hah! A nuclear fan.
What convinces you that we can operate nuclear plants safely. That is to say, what new nuclear energy technologies make this a viable approach?

Elementary, my dear Ivan. I've been instrumental in building 3 of them. They have all been operational for at least 20 years and not a single one has suffered a melt down - and I've also been nominated for village idiot for the 5th straight year. It's not a large village, but a village nonetheless.

Check out these designs. They are pretty impressive:

https://www.pbmr.com/
http://gt-mhr.ga.com/

 

[Ivan Seeking]

Do these use ceramic coated Pu pellets?

Enlighten us about melt-down proof technologies. A friend of mine was working on this but he is now retired, leaving me out of the loop. Also, can you tell us anything about fast-flux reactor technologies?

 

[hitssquad]

Do these use ceramic coated Pu pellets?

They use graphite pellets, each containing a tiny flake of uranium. PBMRs are illegal to implement in the United States because they are so dangerous (the graphite can burn and the reactor is intended to be built without a containment, meaning that each of the thousands of mass-produced pellets needs to have its integrity assured to the same degree that single containments need to have their integrity assured today). Other countries are interested in them though.

 

[Ivan Seeking]

The ceramic approach seemed promising. In principle the separation between the Pu beads [pellet cores] assures that a meltdown is impossible. The ceramics can withstand any temperature that might be reached in the event of a catastrophic cooling failure.

 

[Chronos]

The PBMR design uses a silicon carbide coating on the fuel elements, not graphite [where did that come from?]. Reading the links is recommended. There is no meltdown risk. The status of design reviews in the US can be found here:
http://www.eia.doe.gov/cneaf/nuclear/page/analysis/nucenviss2.html

 

[hitssquad]

Yes, we have no plutonium in our fuel pebbles today

The ceramic approach seemed promising.

As far as I know, there is no such thing as a ceramic approach as regards PBMR fuel pebbles. The PBMR is a slow-neutron reactor. Slow-neutron reactors need neutron moderators. The PBMR uses graphite in its fuel pebbles to slow (moderate) the neutrons.

In principle the separation between the Pu beads [pellet cores]

https://www.pbmr.com/3_pbmr_technical_info/pbmr_technical_contents.htm#PBMRFuel

--
The fuel particles (kernels) consist of uranium dioxide.
--

The ceramics can withstand any temperature that might be reached in the event of a catastrophic cooling failure.

PBMRs, with their graphite fuel pebbles, can also withstand any temperature reached during a loss-of-coolant accident — provided there are no complicating circumstances. If burning jet fuel is dumped on the pebbles (which can easily happen since there is no containment shell for the reactor), they might burn and atmospherically-release tons of aerosolized high-level radioactive waste.

 

[hitssquad]

The tons of flammable graphite used in PBMRs

The PBMR design uses a silicon carbide coating on the fuel elements, not graphite

https://www.pbmr.com/3_pbmr_technical_info/pbmr_technical_contents.htm#PBMRFuel

--
The coated particles are embedded in a graphite matrix as a 50 mm sphere, called the fuel zone.

Adding a 5 mm thick fuel-free graphite zone makes up the fuel sphere with an outer diameter of 60 mm.
--

There is no meltdown risk.

If the graphite burns partly away, the fission fuel might become close enough together for a runaway reaction and subsequent meltdown to occur. Even of there isn't a meltdown, atmospheric fission-product release is possible if the graphite burns.

 

[Ivan Seeking]

As far as I know, there is no such thing as a ceramic approach as regards PBMR fuel pebbles.

There was. Perhaps things didn't work out.

 

[Ivan Seeking]

If gasoline reaches $4.00 a gallon as hinted at by the Bush administration today... Even at $3.00 a gallon we are quicky approaching the point where alternative technologies can compete.

 

[Seafang]

Those are not only silly questions, they are also already answered in the many links provided. Read and learn.

I don't think they are silly questions at all. all of those things you point to are supposedly sources of energy. Good; that's what we need is energy; so why go through the useless step of making hydrogen which we don't need; we need energy.

No amount of prestidigitation is going to evade the problem that we will have to use existing or new sources of energy to make hydrogen to do the same things we could do with that very energy withoput making hydrogen.

I believe it was Franz Kafka, who told a story about a region with a river running through it, and a town on each side of the river, both of them highly prosperous.

Everybody in the town on the west side of the river worked all day at the one factory in town, making marbles out of clay. They imported the finest finely ground clay materials and using the finest molding machinery that swiss engineering could devise, they cleverly molded that clay into perfectly spherical round marbles which the town exported to support all the population.

On the east side of the river, the second prosperous town also had but one factory where everybody worked. The factory had the finest German crushing machinerey that the human mind could conceive, and they all used those machines to produce the most beautiful finely powdered clay material from round marbles of the stuff that they imported in large sacks.

Everybody was kept happy, making hydrogen and then burning it.

 

[Ivan Seeking]

I don't think they are silly questions at all. all of those things you point to are supposedly sources of energy. Good; that's what we need is energy; so why go through the useless step of making hydrogen which we don't need; we need energy.

The point that you seem to keep missing is that there are about a hundred links in this thread and linked threads that answer your questions. Many renewable energy sources are promising, or even succeeding in some markets. I'm not about to list them all again. If you read, you will see that they are already discussed in this thread, and the original archived thread, linked on page one. The real point here is to track the progress of various approaches and to see which are most practical. Also, as suggested by Chronos, even nuclear power may be a part of the solution.

 

[Ivan Seeking]

The Hydrogen Economy: Physics Today

Note: I think part but not all of this was previously posted and available online. Either way, in case you missed it...

If the fuel cell is to become the modern steam engine, basic research must provide breakthroughs in understanding, materials, and design to make a hydrogen−based energy system a vibrant and competitive force.

George W. Crabtree, Mildred S. Dresselhaus, and Michelle V. Buchanan
Since the industrial revolution began in the 18th century, fossil fuels in the form of coal, oil, and natural gas have powered the technology and transportation networks that drive society. But continuing to power the world from fossil fuels threatens our energy supply and puts enormous strains on the environment. The world's demand for energy is projected to double by 2050 in response to population growth and the industrialization of developing countries.1 The supply of fossil fuels is limited, with restrictive shortages of oil and gas projected to occur within our lifetimes (see the article by Paul Weisz in Physics Today, July 2004, page 47). Global oil and gas reserves are concentrated in a few regions of the world, while demand is growing everywhere; as a result, a secure supply is increasingly difficult to assure. Moreover, the use of fossil fuels puts our own health at risk through the chemical and particulate pollution it creates. Carbon dioxide and other greenhouse gas emissions that are associated with global warming threaten the stability of Earth's climate.

A replacement for fossil fuels will not appear overnight. Extensive R&D is required before alternative sources can supply energy in quantities and at costs competitive with fossil fuels, and making those alternative sources available commercially will itself require developing the proper economic infrastructure. Each of those steps takes time, but greater global investment in R&D will most likely hasten the pace of economic change. Although it is impossible to predict when the fossil fuel supply will fall short of demand or when global warming will become acute, the present trend of yearly increases in fossil fuel use shortens our window of opportunity for a managed transition to alternative energy sources.

Hydrogen as energy carrier [continued]

http://www.physicstoday.org/vol-57/iss-12/p39.html

For the pdf: http://www.physicstoday.org/vol-57/iss-12/PDF/vol57no12p39-45.pdf

 

[hitssquad]

Do you think fuel cells are ever going to compete against gasoline, Ivan?

 

[Ivan Seeking]

Do you think fuel cells are ever going to compete against gasoline, Ivan?

I would think so. The automotive designers are already heavily invested in fuel cell technologies, and with gasoline expected to reach as much as $4.00 a gallon soon... When we think about these things, we tend to think in terms of today's prices. Wait until gas here is $6.00 like in other countries. Also, as I have argued all along, if we include the real costs of oil, which includes war and many of the world's ills, fuel cells and alternative fuels are already cheap.

Of course [insert several explitives here] Bush favors making fuel cells that run on gasoline.

 

[hitssquad]

Gasoline externalities and consumer preference

if we include the real costs of oil

It is one thing to cite externalities, and another to imply that people consider externalities when making purchasing decisions. We are talking about whether fuel cells will ever compete against gasoline. Indicative of the lack of consumer motive for seeking alternative fuel technologies might be the facts that fuel-economical vehicles are persistently unpopular and that yearly vehicle miles traveled continually rises.

 

[Ivan Seeking]

First, as indicated, fuel cells and gasoline are not mutually exclusive. Next, orders for Hybrid vehicles are off the charts, in some case at least. As for your assertion that fuel economical vehicles are continually unpopular, I assume that you drive a Buick? It seems that you forget what we used to drive.

Also, test electric vehicles distributed by GM - the EV1 - were tremendously popular among those who were lucky enough [by their accounts] to get one. So I don't really see the basis for your arguments. Needless to say that this all neglects the coming reality of $4, and eventually $6 per gallon, and more. Finally, the ever increasing taxes on fuel are no accident, and externalities justify even more tax; much, much more.

The costs to all of us in money, environmental damage, health related issues and costs, which are huge btw, political agendas, military expenditures, etc, etc, and ultimately the cost in lives associated with the petro-economy are all very real. The benefits of an H2 economy - which appears to include H2 powered fuel cells - in all respects are equally real. So it not only makes sense on a personal/financial level, it makes sense from macro-economic and political perspectives as well; at the right time.

If you feel that alternative fuels are practical, but not fuel cells, I can only defer to the automotive engineers and designers who should know. They seem to feel that these will emerge as a practical technology. I think it will take time, and transitional technologies may be more practical; perhaps even H2 combustion engines, as some companies are working on this. I also liked your hydrogen pellets linked some pages ago. Those seem promising [edit] but I was concerned about the efficiency of the entire process. Of course, you bypass all sorts of problems by having a solid to transport and store, rather than a high pressure gas. So it seems to me that any additional energy costs in the production of these pellets might be recaptured in the distribution system.

 

[hitssquad]

I also liked your hydrogen pellets linked some pages ago.

Boron?
http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.html

 

[Ivan Seeking]

Boron?
http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.html

Hmmm, I may be mixing up your post with the pellets discussed in the Nova special. I thought that you had posted something very similar, but not Boron.


An intersting story today:

Windmills in the Sky
Australian engineer Bryan Roberts wants to build a power station in the sky -- a cluster of flying windmills soaring 15,000 feet in the air -- but is having trouble raising enough money to get the project off the ground.

After 25 years of research, Roberts has designed a helicopter-like rotorcraft to hoist a wind turbine high into the air, where winds are persistent and strong. The craft, which is powered by its own electricity and can stay aloft for months, feeds electricity to the ground through a cable.

Roberts, a professor of engineering at the University of Technology, Sydney, believes there is enough energy in high-altitude winds to satisfy the world's demands. Wind-tunnel data suggests a cluster of 600 flying electric generators, or FEGs, could produce three times as much energy as the United States' most productive nuclear power plant. [continued]

http://www.wired.com/news/planet/0,2782,67121,00.html?tw=wn_tophead_2

 

[Ivan Seeking]

Solar Tower of Power Finds Home

The quest for a new form of green energy has taken a significant step with the purchase of a 25,000-acre sheep farm in the Australian outback. The huge alternative energy project isn't driven by manure, but by a 1-kilometer-high thermal power station called the Solar Tower.

Announced several years ago, the 3,280-foot Solar Tower is one of the most ambitious alternative energy projects on the planet: a renewable energy plant that pumps out the same power as a small reactor but is totally safe. If built, it will be nearly double the height of the world's tallest structure, the CN Tower in Canada.

..."Solar chimneys (towers) have become a hot area of research recently," said S.A. Sherif, a professor of mechanical and aerospace engineering at the University of Florida, who wrote several papers on the technology in the early 1990s and is the technical editor of the http://www.ises.org/ises.nsf/0/8eb9a73ea902c053c12568be004fa01a?OpenDocument . Although expensive to build, solar towers "essentially produce energy for free," said Sherif. In addition, the technology has been proven to work: A 650-foot solar tower was built in Manzanares, Spain, in 1981 by German structural engineers Schlaich Bergermann and Partner. Producing 50 kilowatts, it operated for seven years. But with oil prices at $15 a barrel in the mid-1980s, there was little interest in building a larger one, Sherif said. [continued]

http://www.wired.com/news/technology/0,1282,66694,00.html

 

[Ivan Seeking]

Please see also the new posts above:

About H2 ICE: Internal Combustion Engines. They're here...
https://www.physicsforums.com/showthread.php?t=70653

Also, this seems to be a very cool site and one that I have never seen:
H2 CARSBIZ
http://www.h2cars.biz/artman/publish/index.shtml

 

[Cliff_J]

I thought the general consensus a while back was the solar tower is bogus and a borderline urban myth. That basically its extremely tough to pump water to the levels described and the structure would be incredibly expensive to build along with other issues that would need to be carefully managed. Managed so well that most figures (as I recall) showed a negative energy output.

 

[Ivan Seeking]

I thought the general consensus a while back was the solar tower is bogus and a borderline urban myth. That basically its extremely tough to pump water to the levels described and the structure would be incredibly expensive to build along with other issues that would need to be carefully managed. Managed so well that most figures (as I recall) showed a negative energy output.

I hadn't heard of this effort or what you describe. Could that have been something else? I didn't see that this would require pumping water.

It seems that Wired does push the edge a bit, but the claims of earlier efforts are quite specific.

 

[hitssquad]

I thought the general consensus a while back was the solar tower is bogus and a borderline urban myth. That basically its extremely tough to pump water to the levels described

It channels rising hot air which drives turbines. It doesn't use water:
http://www.wired.com/news/technology/0,1282,66694,00.html

--
The Solar Tower is hollow in the middle like a chimney. At its base is a solar collector -- a 25,000-acre, transparent circular skirt. The air under the collector is heated by the sun and funneled up the chimney by convection -- hot air rises. As it rises, the air accelerates to 35 mph, driving 32 wind turbines inside the tower, which generate electricity much like conventional wind farms.
--

 

[Billy T]

I only read last page and first two of this long thread, so hope i am not repeating. Most energy is in some form "solar energy" (coal old version, fission even older and not from our sun but earlier star) Only exception is tidal power. As many have pointed out, hydrogen is not an energy source. Most would prefer to live off the current solar input, stop burning fossil fuels, avoid nuclear, etc. The hydrogen economy could do so, but it will still take a lot of area as sunlight is not very concentrated. Few realize that solar cell generated electricity can not compete with the current sources even if the solar cells had zero cost the so called "BOS cost" (Balance of System) for land, structures, periodic repair,cleaning, conversion to AC from the DC generated, lots of interconnect wires, and a few other items are too expensive.

So what can one do? Use a natural solar energy collection system (sugar cane). It has about the same or slightly better efficiency than common economical solar cells (and the theoretical limit is 21% for any based on silicon, which is nearly ideal for the solar spectrum)

Production of a liquid fuel (alcohol) from sugar cane is easy and relatively cheap. The residue is good for feed to cattle, enrich the soil, and sequester carbon - I.e. removes CO2 from the air economically as only vegetation (green algie is "vegetation") can. Brazil were I live has been running cars on alcohol in large numbers for a couple of decades. Currently alcohol cost about R$1.20 /liter and gasoline about R$2.20 i.e. alcohol is much less costly and there is no funny economics in this. I don't have the current sales data but bet 9 out of 10 new cars sold in Brazil will run on alcohol.

Brazil would love to sell it to US and their well developed alcohol/ gas in any ratio motors. It is so cheap here because land and labor are cheap, the growing season is 12 months each year. Obviously the corn growing farmers of Iowa and their market for octane enhancement etc. "gasohol" would suffer if Brazil were allowed to export to US. Also important is fact that no Brazilian votes were available or of interested to a US government dominated by former oil company owners and related industry CEOs.

Never mind new hydrogen economy - get some real economy now with 20 year old Brazilian technology. Remove US import barriers.

 

[russ_watters]

I thought the general consensus a while back was the solar tower is bogus and a borderline urban myth. That basically its extremely tough to pump water to the levels described and the structure would be incredibly expensive to build along with other issues that would need to be carefully managed. Managed so well that most figures (as I recall) showed a negative energy output.

Are you thinking of the guy who wanted to pump fuel into space on a carbon nanotube tether/pipe?

No, as others have said, the solar tower idea just uses solare heating of the desert and would work - in theory. But that "in theory" part is a real kicker: The worlds tallest freestanding structure is about 500m high. They want to build a 1000m tower. Doesn't seem too realistic to me from an engineering standpoint.

Oh, and the other problem is that the company that's proposing it is a scam.

edit: I'm not a big fan of Wired - they publish a lot of crap, but this is a little rediculous:

But the purchase of the farm, which cost $1 million, near Mildura, Victoria, is a "very big step" in getting the project built, Davey said.

So far, the main impediment to building the tower has been the cost, with estimates ranging from $500 million to $750 million.

Hmm... obtaining 1/750th of the needed funding (guestimated) is "a very big step"?

And this land - at $185 an acre? I'm guessing its in the middle of nowhere.