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Thread: Hydrogen - The ultimate in portable solar energy via electrolysis of water. But Is it viable?

  1. #1 Hydrogen - The ultimate in portable solar energy via electrolysis of water. But Is it viable? 
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    Water can be split into molecular hydrogen and oxygen by electrolysis from photovoltaics. If the hydrogen is trapped and liquefied, it can be transported all over the world.

    Hydrogen has many advantages for powering things, especially by fuel cells. Its primary pollutant is water, something we can all live with. Most importantly, it works even when the sun isn't shining!

    It would take enormous solar farms in deserts of the world (with abundant water of course), and all the infrastructure required to produce, liquefy and transport the hydrogen.

    Many tend to note its flammability, and of course the Hindenburg disaster. But as a portable energy source, it is actually much safer than petrol, which falls to the ground and burns itself out around you. Hydrogen rises rapidly, quickly carrying any flaming plumes away from a "spill".

    But is it feasible to produce, store and transport hydrogen as a fuel?

    Or will some other technology (e.g. advanced, light-weight batteries) be the better course?


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    I don't expect Hydrogen will become a major transport fuel any time soon - too much associated infrastructure would be needed. Besides overall much better energy efficiencies, battery EV's can make use of existing electricity distribution systems in ways that H2 cannot. Maybe H2 - eventually - for shipping? Batteries are getting cheaper and better - close to 90% price drop for large scale Li-Ion over the last decade, promising developments that reduce costs and extend battery life; 3 million km/2 million mile being close to commercially viable. Durability will be profoundly important, especially to household and grid storage uses; long working life greatly reduces overall costs.

    Hydrogen produced for industrial /energy storage uses on site, fed power from solar and wind (through those same electricity electricity grids) makes more sense to me. A lot of modern gas fired power plants can cope with high levels of H2 in the fuel mix, some up to and above 90%; having on-site H2 production, where storage does not have to be at the extreme pressures transport fuel and transport of that fuel requires (ie less onerous engineering requirements) seems like a good interim step to make better use of existing plants as backup to renewables whilst still reducing emissions. Ultimately they probably won't compete against fuel cells in place of H2 burning but in the meantime it may extend the life of existing gas plants.

    Hydrogen for steel production and for fertiliser manufacture has great promise - is our best pathway to zero emissions for these and should be given priority.


    Last edited by Ken Fabos; January 21st, 2021 at 05:47 PM.
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    Charging all those batteries on the existing electricity distribution systems is going to produce a lot of greenhouse gases, unless they are powered by photovoltaics, wind or massive battery arrays charged by same. And what is the environmental cost of making and disposing of all these batteries?

    One can appreciate the value of batteries for personal uses up to cars, but H2 to power and heat/cool habitats, and supply industries as you noted, especially seems ideal in developing countries which have little infrastructure for anything other than oil for transportation, and coal for electricity. Maybe they can lead the way on H2. They should have an incentive to use H2. Their population density will require it or batteries at some point. But photovoltaics should still rule, even with batteries.

    Fuel cells for homes, and H2's industrial apps seems like a combination scheme, with batteries as a bridge to more H2 uses sounds likely. Time will tell.

    Thanks for the fine overview on batteries, etc., Ken.
    Last edited by Double Helix; January 21st, 2021 at 11:09 PM.
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    Quote Originally Posted by Double Helix View Post
    Water can be split into molecular hydrogen and oxygen by electrolysis from photovoltaics. If the hydrogen is trapped and liquefied, it can be transported all over the world.

    Hydrogen has many advantages for powering things, especially by fuel cells. Its primary pollutant is water, something we can all live with. Most importantly, it works even when the sun isn't shining!

    It would take enormous solar farms in deserts of the world (with abundant water of course), and all the infrastructure required to produce, liquefy and transport the hydrogen.

    Many tend to note its flammability, and of course the Hindenburg disaster. But as a portable energy source, it is actually much safer than petrol, which falls to the ground and burns itself out around you. Hydrogen rises rapidly, quickly carrying any flaming plumes away from a "spill".

    But is it feasible to produce, store and transport hydrogen as a fuel?

    Or will some other technology (e.g. advanced, light-weight batteries) be the better course?
    Are you sure about this? The critical point for H2 is 33K. And to get liquid H2 at atmospheric pressure you have to cool it to 20K. Are there really proposals to transport hydrogen at such lowtemperatures? I thought hydrogen was stored and transported as a pressurised gas.
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    Quote Originally Posted by exchemist View Post
    Are you sure about this? The critical point for H2 is 33K. And to get liquid H2 at atmospheric pressure you have to cool it to 20K. Are there really proposals to transport hydrogen at such lowtemperatures? I thought hydrogen was stored and transported as a pressurised gas.
    No, I am not sure about it all. which is why I posted the thread, and get informed responses like yours and Ken's.

    The concept was stitched together from various notions I have read about liquid fuels. LNG is a cryogenic liquid that is transported all over the world in large tankers. It seemed likely H2 could be transported like this, but did not know the details. Fueling the space shuttle tanks with H2 and O2 suggested liquid hydrogen for many applications.

    Looking into it more, it is largely transported as a high pressure gas. So it does appear that transport as a liquid won't work (without some marvelous invention!) since maintaining the low temperatures is a problem. Liquid hydrogen as a fuel appears only practical for storage near the point of manufacture.

    Still, I read about cars being run on H2-powered fuel cells, and wondered about how they are fueled, and the distribution network it would require (apparently from large pressurized trucks?). Apparently metal hydrides are involved. But they may not be practical for bulk transport.

    Perhaps you could give me a brief on this.
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    Quote Originally Posted by Double Helix View Post
    Quote Originally Posted by exchemist View Post
    Are you sure about this? The critical point for H2 is 33K. And to get liquid H2 at atmospheric pressure you have to cool it to 20K. Are there really proposals to transport hydrogen at such lowtemperatures? I thought hydrogen was stored and transported as a pressurised gas.
    No, I am not sure about it all. which is why I posted the thread, and get informed responses like yours and Ken's.

    The concept was stitched together from various notions I have read about liquid fuels. LNG is a cryogenic liquid that is transported all over the world in large tankers. It seemed likely H2 could be transported like this, but did not know the details. Fueling the space shuttle tanks with H2 and O2 suggested liquid hydrogen for many applications.

    Looking into it more, it is largely transported as a high pressure gas. So it does appear that transport as a liquid won't work (without some marvelous invention!) since maintaining the low temperatures is a problem. Liquid hydrogen as a fuel appears only practical for storage near the point of manufacture.

    Still, I read about cars being run on H2-powered fuel cells, and wondered about how they are fueled, and the distribution network it would require (apparently from large pressurized trucks?). Apparently metal hydrides are involved. But they may not be practical for bulk transport.

    Perhaps you could give me a brief on this.
    I don't know much about this, though I did read some years ago that metal hydrides were being investigated. I don't know where that has got to. My understanding is that most transport fuel application use high pressures gas cylinders.

    The problem with both high pressure gas and, even more, liquified hydrogen is the large energy cost in compressing or liquefying it, compared to its relatively modest calorific value per unit volume as fuel. In addition, with liquefied hydrogen you have the issue of boil-off gas. You can't just park your car in the garage for 3 days, because hydrogen will be boiling off all the time, as heat leaks through the tank insulation. Shell, who I used to work for, has some pilot hydrogen filling stations, but these are based on recharging high pressure gas cylinders: https://www.shell.co.uk/a-cleaner-en.../hydrogen.html
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    There clearly appears to be a problem in storage and transport. After a search, wiki has some good ideas about all this, and the best solution right now are the hydrides, and then I read this : "the persistent problems are the % weight of H2 that they carry and the reversibility of the storage process." (1)

    Of course that makes sense. If one can get enough H2 back from the hydride, then you can make this work if the amount of hydrogen recovered is sufficient.

    1. https://en.wikipedia.org/wiki/Hydrogen_storage

    The article does mention liquid H2 cars in Japan. So running a search on that reveals that Kawasaki Heavy Industries has developed a liquid hydrogen tanker for supplying liquid H2 to many fueling stations around Japan, much to my surprise (2).

    (2). https://www.popularmechanics.com/sci...hydrogen-ship/

    Apparently my prospects for global distribution of liquid hydrogen from solar farms is not so far-fetched after all. The Japanese are very clever people!

    And then I found this from industryweek.com (3) :

    "There are currently 2,200 fuel-cell cars in Japan with 91 hydrogen stations, according to the industry ministry, but a lack of stations has been a major hurdle for carmakers as they seek to boost production."

    It appears they are running with liquid hydrogen as they mention the boil off problem. Again, my dream may yet be realized. Again, the ultimate in portable solar energy may be liquid hydrogen. It all depends on efficiency vs. that from batteries, as Ken mentioned.

    (3) https://www.industryweek.com/technol...rogen-stations
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    unless they are powered by photovoltaics, wind or massive battery arrays charged by same. And what is the environmental cost of making and disposing of all these batteries?
    Like Hydrogen production, the whole idea is to use clean energy to make and charge batteries - large batteries are appearing as integrated elements in many new solar and wind projects in Australia. Without the growth of wind and solar they wouldn't be being built. Yes, there are environmental problems but there is also awareness of them - and efforts to develop effective recycling as well as R&D into other battery chemistries, including ones that are low in toxicity. As the proportion of clean energy in electricity supplies grow the embedded emissions in manufacturing goes down.

    My understanding is coal ash is the second most abundant waste product in the world after CO2 - CO2 exceeds all other waste combined, by a huge margin but it ought not be a surprise that there's a lot of coal ash from making that CO2 as well. It has high levels of toxic heavy metals and presents a major environmental problem right now.
    Last edited by Ken Fabos; January 22nd, 2021 at 07:45 PM. Reason: clarity
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    What do you think about using hydrogen as a motor fuel? I don't understand the very sense of it. If it is all about zero emissions at the global level, then electricity and/or biofuels satisfy to the same criteria. And they are cheaper and more convenient than hydrogen.
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    Quote Originally Posted by Stanley514 View Post
    What do you think about using hydrogen as a motor fuel? I don't understand the very sense of it. If it is all about zero emissions at the global level, then electricity and/or biofuels satisfy to the same criteria. And they are cheaper and more convenient than hydrogen.
    As you know, photovoltaics (PVs) convert water directly into H2 and O2. Using this hydrogen in a car circumvents all the electrical transmissions to distant charging stations, and the inherent loss of efficiency in that regard. Losses in making and transporting hydrogen do not result in increases in CO2 since those processes would also be driven by H2 produced from PVs, or directly from the PVs.

    Moreover, most of the electricity to charge EVs still comes from some form of fossil fuels. About 60% of electricity is presently generated by fossil fuels. So with conversion to renewables without massive CO2 discharges, the EVs are getting us closer to net neutral, but that goal seems rather distant, if at all attainable.

    It would seem hydrogen should have some place in transport, heating, lighting, etc., using localized, individual fuel cells. No enormous and devastating electrical grid failures which can occur for various reasons. And no losses in transmission. And these fuel cells put out continuous power, 24/7, rain. shine or night time!

    The bottom line is H2 from PVs do not produce CO2, only water. You get back what you put in. There may be negatives on some side of this, but the greatest decreases in CO2 releases is rather attractive to some.

    What do you think? There are always more to these technologies than such simplifications, which is why I started the thread.
    Last edited by Double Helix; June 10th, 2021 at 10:10 PM.
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    As you know, photovoltaics (PVs) convert water directly into H2 and O2.
    Is it more efficient than produce electricity locally with help of PV on the roofs of charging stations or building's roofs? Or even grow algae and produce biodiesel or ethanol in the same manner?
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    Quote Originally Posted by Stanley514 View Post
    As you know, photovoltaics (PVs) convert water directly into H2 and O2.
    Is it more efficient than produce electricity locally with help of PV on the roofs of charging stations or building roofs? Or even grow algae and produce biodiesel or ethanol in the same manner?
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    All good questions.

    The bottom line will be how it all works out in real time. Batteries are the key to EVs and other numerous E-applications.

    But total local reliance on PVs for electrical supplies would require massive battery banks to get you through the dark, or use some other form of generation when the PVs are down.

    Major advances in batteries could blow everything else out of the water, as long as they are not a problem with cost/disposal/recycling.

    Both approaches (PVs and H2) sound like great ideas, but the devil is always in the details. And there is no crystal ball to tell us what is going to work out long haul on a large scale.

    Doubtless time will tell.
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    Quote Originally Posted by Double Helix View Post
    But total local reliance on PVs for electrical supplies would require massive battery banks to get you through the dark, or use some other form of generation when the PVs are down.
    Superflywheels could store energy at night?
    Although the exact value of energy density of a superflywheel would depend on the material used, it could theoretically be as high as 1200 Wh (4.4 MJ) per kg of mass for graphene superflywheels.
    Flywheel - Wikipedia

    Thermal energy storage? Could be converted to electricity with help of 35% efficient Stirling engines.
    Thermal energy storage - Wikipedia

    Plug-in hybrids could run on biofuel at night.

    Solid state Lithium-Sulfur and Zinc-air batteries could eventually become perhaps almost as energy dense as liquid Hydrogen (per volume). The problem is to make them cheap enough and well rechargeable.
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    Quote Originally Posted by Stanley514 View Post
    Quote Originally Posted by Double Helix View Post
    But total local reliance on PVs for electrical supplies would require massive battery banks to get you through the dark, or use some other form of generation when the PVs are down.
    Superflywheels could store energy at night?
    Although the exact value of energy density of a superflywheel would depend on the material used, it could theoretically be as high as 1200 Wh (4.4 MJ) per kg of mass for graphene superflywheels.
    Flywheel - Wikipedia

    Thermal energy storage? Could be converted to electricity with help of 35% efficient Stirling engines.
    Thermal energy storage - Wikipedia

    Plug-in hybrids could run on biofuel at night.

    Solid state Lithium-Sulfur and Zinc-air batteries could eventually become perhaps almost as energy dense as liquid Hydrogen. The problem is to make them cheap enough and well rechargeable.

    You have presented an interesting variety of approaches for powering systems when the PVs are not on-line. Some could certainly work out. Batteries seem to remain the biggest advantage, and could be used to power many applications. The biggest problems are the recharge times, cost and longevity. As noted earlier, battery technology could certainly rule in the end purely due to simplicity.

    But there is still interest in hydrogen as a source of fuel. Its primary advantages are a simple, "one type" fits all applications, and no need for charging down times. Both are major advantages, and when generated from PVs there is no issue about CO2 balance.

    However, the EVs are currently ruling sales, and may stall the development of hydrogen from PVs for a future where no carbon is involved at all. As noted before, it seems likely that the two, batteries and hydrogen, will be major players in the future for various applications. Given enough time and investment, it seems like one or the other will dominate in the future, which could still be decades off. Tech developments will likely determine this.

    While economics should be determinative, there are some powerful players in this who could upend any fair race for the ultimate in eco-friendly energy technology.
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    Quote Originally Posted by Double Helix View Post

    1) But there is still interest in hydrogen as a source of fuel. Its primary advantages are a simple, "one type" fits all applications, and no need for charging down times.

    2) As noted before, it seems likely that the two, batteries and hydrogen, will be major players in the future for various applications.
    1) I don't understand why the issue with charging times is so critical. In my opinion the best solution in the near future would be a plug-in hybrid with 100-130 miles electric range which runs 95% of time on electricity and 5% on biofuel annually. Perhaps in the nearest 50 years it will be cheaper and more convenient option than all-electric or all-hydrogen ones. You may charge it leisurely at night near your dwelling, when electricity is cheaper and run on biofuel only in the case of emergency or a long distance travel. I think it is realistic to equip even all the apartment houses with a charging points. Each point for a one driver. If you want to rely on centralized charging points only, for some strange reason, then perhaps supercapacitors and flywheels could reduce charging times in the more distant future?
    2) Could you provide some principal argument in support of electricity + hydrogen combo vs. electricity + biofuel? I afraid that hydrogen can never beat biofuels in energy density and neither in price in the nearest 50 years. Probably some extremely cheap energy source similar to a tabletop cold fusion has to be discovered first to cancel any worries about hydrogen price completely.
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    Quote Originally Posted by Stanley514 View Post
    Could you provide some principal argument in support of electricity + hydrogen combo vs. electricity + biofuel?
    Not at this time. Too much development going on. Which is why I posted this thread and asked the question about hydrogen:

    "But Is it viable?"

    People like you give me much to think about. I read about the concept of H2 from PVs years ago, and it seems so optimal for reducing CO2. Still, there is much tech to try and find out what is the best approach.

    Of course the recharge time of batteries is an issue with many. Nobody wants to wait to refuel.

    Looked up solid state batteries* that you brought up and they sure sound great, though lots of tech problems. But the concept seems ideal.

    * https://en.wikipedia.org/wiki/Solid-state_battery

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    Quote Originally Posted by Double Helix View Post
    Of course the recharge time of batteries is an issue with many. Nobody wants to wait to refuel.
    Not so much for plug-in hybrids, I think. If you got an emergency and can't wait, you just run on biofuel whenever you want. And they are likely going to be cheaper than long-range all-electric for a several more decades, at least. I think modern infrastructure is poorly suitable both for all-electric or PV-to-hydrogen options. If there is a major accident on a power plant then all the transport in entire region will stall and disaster will follow up. PV's are too dependent on weather conditions. First, a huge amount of back-up power plants or power banks have to be built. But still hybrids which run on two different types of energy are more reliable. Especially in the case of wars or some major disasters.
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    Quote Originally Posted by Stanley514 View Post
    I think modern infrastructure is poorly suitable both for all-electric or PV-to-hydrogen options.
    There is no doubt since infrastructure makes or breaks any alternate approach to hydrocarbons, which of course are everywhere. Right now, infrastructure going forward for all-electric has a big leg up on H2.


    Quote Originally Posted by Stanley514 View Post
    But still hybrids which run on two different types of energy are more reliable. Especially in the case of wars or some major disasters.
    Good point. And it should be remembered that many internal combustion engines, of which there are a great many, useful for decades to come, can be converted to burn H2.

    This could salvage a role for H2 where electric cannot compete, and provide a launching pad to compete later with the electrics. Probably depends a lot on battery advances, and PV-to-hydrogen infrastructure, which currently is very limited anyway. Europe is moving with wind powered H2 production, and Japan is going with the PV route, or so it looks like from this article:

    "Japan and EU race to develop 'green hydrogen'"

    https://asia.nikkei.com/Spotlight/En...reen-hydrogen2
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    Quote Originally Posted by Double Helix View Post
    Europe is moving with wind powered H2 production, and Japan is going with the PV route, or so it looks like from this article:

    "Japan and EU race to develop 'green hydrogen'"

    https://asia.nikkei.com/Spotlight/En...reen-hydrogen2
    Sadly, everything associated with hydrogen requires huge govt. subsidies and rises a question on why does it jeopardize cheaper green technologies. For example, one of the strangest things I've heard about are hydrogen powered trains. What are the problems with railroads electrification?
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    Quote Originally Posted by Stanley514 View Post
    Sadly, everything associated with hydrogen requires huge govt. subsidies......
    Many very successful technologies required these subsidies because the private sector does not want to risk their dough on major gambles. The future of energy in this case. But many pharmaceuticals, and other projects involving risky prospects for success are going to get major subsidies if the payoff is big enough. I believe some of these vaccines were developed by such means. And of course the moon missions started a wave in micro-electronics.

    Sometimes the "powers that be" have to force the issue by greasing the wheels of major projects to yield high end results. I am all for it if that is the only way it can be reasonably tested. The payback on something like this is too hard to resist.
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    Quote Originally Posted by Double Helix View Post
    Many very successful technologies required these subsidies
    But you always need to take the competing technologies into account. And compare the projected results.
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    Quote Originally Posted by Stanley514 View Post
    Quote Originally Posted by Double Helix View Post
    Europe is moving with wind powered H2 production, and Japan is going with the PV route, or so it looks like from this article:

    "Japan and EU race to develop 'green hydrogen'"

    https://asia.nikkei.com/Spotlight/En...reen-hydrogen2
    Sadly, everything associated with hydrogen requires huge govt. subsidies and rises a question on why does it jeopardize cheaper green technologies. For example, one of the strangest things I've heard about are hydrogen powered trains. What are the problems with railroads electrification?
    Cost, for lines that are not heavily used. Electrification requires a lot of infrastructure. If there is a role for hydrogen it will be for diesel powered lines that are uneconomic to electrify.
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    [QUOTE=exchemist;632593]
    Quote Originally Posted by Stanley514 View Post
    Electrification requires a lot of infrastructure.
    Even more than hydrogen? Hard to believe. Also, there are such alternatives as biofuel and aluminum-air fuel cells. The later could be especially attractive for aircrafts as they are much more energy dense than hydrogen (per volume) and completely non-flammable/non-explosive in the case of accidents. An accident which involves a large hydrogen plane could turn to a lager disaster than "September 11".
    Negative? How a Navy veteran refused to accept a ‘no’ to his battery invention | TechCrunch
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    Quote Originally Posted by Stanley514 View Post
    For example, one of the strangest things I've heard about are hydrogen powered trains. What are the problems with railroads electrification?
    The best approach for trains may be on-board hydrogen as fuel. And they already have them*.

    Quoting from the article emphasizes the need for government support for a push-start:

    "The technology faces the classic chicken-and-egg conundrum: Suppliers hesitate to build the big clean-production facilities needed to bring down costs until demand is more certain, while most customers are waiting for lower prices before switching fuels. Trains can help unblock the market because they offer an unusually predictable, long-term source of demand. Government incentives will also accelerate development."

    end quote

    Hydrogen clearly has some major support going for it.


    "Hydrogen-Powered Trains Have Arrived "

    * https://www.wsj.com/articles/hydroge...ed-11622025494


    see also:

    https://en.wikipedia.org/wiki/Hydrail
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    Quote Originally Posted by Double Helix View Post
    "The technology faces the classic chicken-and-egg conundrum: Suppliers hesitate to build the big clean-production facilities needed to bring down costs until demand is more certain, while most customers are waiting for lower prices before switching fuels. Trains can help unblock the market because they offer an unusually predictable, long-term source of demand. Government incentives will also accelerate development."
    Could you provide any researches which show that hydrogen as a motor fuel going to be cheaper than electricity or biofuel when hydrogen infrastructure will be fully developed and hydrogen mass produced? And take in account the projected price of biofuel from algae and bio-waste when it will be mass produced as well? For now some researches show rather opposite. That hydrogen cars/infrastructure are in principle less efficient and more expensive than electric or hybrid cars.
    Battery-powered models have an overall efficiency of 70-90 percent, while fuel cells vehicles are limited to 25-35 percent, according to Volkswagen.

    Mercedes-Benz gives up on fuel cell cars – report | Clean Energy Wire

    I suggest that both numbers are big exaggeration if we talk about power plant or roof PV's to wheels efficiency. But still hydrogen evidently looses.
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    Quote Originally Posted by Stanley514 View Post
    Could you provide any researches which show that hydrogen as a motor fuel going to be cheaper than electricity or biofuel when hydrogen infrastructure will be fully developed and hydrogen mass produced?
    Nothing more to offer than those articles which indicate some big players are moving forward with hydrogen. There is a lot of money being spent on it, so there must be something there. The cost for H2 is higher, and the success will depend on getting that down. But economy of scale is the biggest aspect. They need something like H2 powered trains to provide a market and then expand into other areas.

    As far as efficiency goes, not sure but recall numbers more like 60% for H2 fuel cells. VWs data may be obsolete. But efficiency at the power end is not the whole story. The driving force behind the move to H2 is zero carbon, which is not in the equation with H2. If the efficiency is good enough and it is cost effective, people will adopt it. Some clearly believe it is the ultimate approach to eliminating most aspects of mass carbon dumping into the atmosphere, and zero questions about how to control it. H2 has a lot going for it. We will have to wait and see what happens.
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    Quote Originally Posted by Double Helix View Post
    As far as efficiency goes, not sure but recall numbers more like 60% for H2 fuel cells.
    Typical PEM fuel cells are no more than 45-50% efficient in real conditions.
    Proton-exchange membrane fuel cell - Wikipedia
    Don't forget looses on electrolysis, hydrogen compression to 700 bars, evaporation, infrastructure maintenance, the price of fuel cells, etc. You cannot refuel it near your home or regular parking lot (in difference from an electric one). You cannot recuperate braking without a battery.
    Usually a fuel cell car consumes 2.4 times more energy than a battery electric car, because electrolysis and storage of hydrogen is much less efficient than using electricity to directly load a battery.

    Fuel cell vehicle - Wikipedia
    Last edited by Stanley514; June 13th, 2021 at 05:52 AM.
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    Hydrogen as a primary fuel source is still alive, and growing (1).

    Quoting from (1):

    "Manufacturers of large trucks and commercial vehicles are beginning to embrace hydrogen fuel cell technologies as a way forward. So are makers of planes, trains and passenger vehicles. Transportation is the single biggest U.S. contributor to climate change, which is why hydrogen power, in the long run, is seen as a potentially important way to help reduce carbon emissions."

    end quote

    Elon Musk has referred to fuel cells as "fool cells".

    But are we really going to power buses, trains, planes and large ships with batteries? Not likely. But hydrogen offers this very possibility - with zero carbon and zero battery issues (2).

    Quoting from (2):

    "Governments and leaders around the world are rallying behind hydrogen as a key component to their plans for addressing climate change, not just in the transportation sector but across their entire energy grid. Consider that the European Commission announced its Hydrogen Strategy for a climate-neutral Europe in which it said that hydrogen is "an important part of the solution to meet the 2050 climate neutrality goal of the European Green Deal.""

    and another quote from (2):

    "Meanwhile, at Tesla's Battery Day in September, Musk acknowledged that his vision for lithium-ion batteries is more complicated than he expected, on a longer technological timetable and not scalable enough to solve the world's most pressing climate problems. Yet surprisingly, in spite of an unprecedented surge in international interest, there was no mention of the clearest solution for zero-emission energy that would meet his own climate goals: hydrogen."

    end quotes


    Time will tell about who is the fool on fuel cells.


    "Hydrogen-powered vehicles: A realistic path to clean energy?"

    1. https://abcnews.go.com/US/wireStory/hydrogen-powered-vehicles-realistic-path-clean-energy-79439859


    "It's Time For Elon Musk To Admit The Significance Of Hydrogen Fuel Cells"

    2. https://www.forbes.com/sites/forbest...en-fuel-cells/
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  30. #29  
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    Quote Originally Posted by Double Helix View Post
    Hydrogen as a primary fuel source is still alive, and growing.
    Only because of govt. subsidies, mostly.
    Quote Originally Posted by Double Helix View Post
    But are we really going to power buses, trains, planes and large ships with batteries?
    Isn't biofuel more convenient than hydrogen?
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    Quote Originally Posted by Stanley514 View Post
    Only because of govt. subsidies, mostly.
    Those subsidies have given us lots of tech that were later commercialized. Medical advances are often heavily subsidized. Sometimes it's the only way for some techs to develop.

    Quote Originally Posted by Stanley514 View Post
    Isn't biofuel more convenient than hydrogen?
    Right now perhaps, but hydrogen is the ultimate green, along with solar. The solar panels were developed by subsidies too, and space exploration.
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    Quote Originally Posted by Double Helix View Post
    Right now perhaps, but hydrogen is the ultimate green, along with solar. The solar panels were developed by subsidies too, and space exploration.
    Why biofuel is less green than hydrogen? For now there is no even theoretical way to pack hydrogen as dense as biodiesel or ethanol. And it makes senseless the very undertaking with hydrogen.
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    [QUOTE=Stanley514;633104]
    Quote Originally Posted by Double Helix View Post
    Why biofuel is less green than hydrogen? For now there is no even theoretical way to pack hydrogen as dense as biodiesel or ethanol. And it makes senseless the very undertaking with hydrogen.
    When produced by windmills or photovoltaics, "green" hydrogen is the ultimate in portable fuel. Nothing from it but energy and water. Why do you think they are spending so much on it?! They are not idiots, or "senseless".

    If there is no "theoretical way" to pack hydrogen to sufficient operational density, how can they be running forklifts, cars, and large buses on it? This is known as empirical evidence to support the concept. It is not the least bit theoretical - it is reality. (Some theories have a way of turning out to be wrong.)

    Are you even bothering to read the attached articles? It would not appear to be the case. You seem be locked into some kind of anti-hydrogen campaign when there is a lot of money getting into hydrogen. Something tells me these people have a better idea about it than we do or they would not be spending the time and money.

    Future research holds the key. Again, and for the last time, all these countries, the U.S., Japan, all those in the E.U., etc. would not be spending billions on it if there was no way for it to work.

    They are doing this because hydrogen is already working.
    Last edited by Double Helix; August 17th, 2021 at 04:01 PM.
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    [QUOTE=Double Helix;633108]
    Quote Originally Posted by Stanley514 View Post
    If there is no "theoretical way" to pack hydrogen to sufficient operational density
    Energy density (MJ/L):
    Biodiesel - 33-35
    Ethanol - 18-21
    Hydrogen (liquid, -250 C) - 8
    Hydrogen (compressed, 700 bars) - 5.6
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    [QUOTE=Stanley514;633122]
    Quote Originally Posted by Double Helix View Post
    Quote Originally Posted by Stanley514 View Post
    If there is no "theoretical way" to pack hydrogen to sufficient operational density
    Energy density (MJ/L):
    Biodiesel - 33-35
    Ethanol - 18-21
    Hydrogen (liquid, -250 C) - 8
    Hydrogen (compressed, 700 bars) - 5.6

    It is clearly obvious that density aspects are not an issue because of billion$ being spent on hydrogen research, and on functional transportation of nearly any kind you can think of.

    All theories aside, quoting from Forbes below:

    "Hydrogen technologies are not yet widely used, but some countries are investing heavily in their future. Japan, which sees hydrogen as a way to reduce costly energy imports, hopes to have 800,000 hydrogen-powered vehicles by 2030 and to reduce the cost of hydrogen production by 90% by 2050 making it cheaper than natural gas."

    end quote

    So the defining issue here is not density, but the large amounts of money spent on hydrogen R & D, and current real applications. That is definitive, regardless of energy density's theoretical aspects.

    You can post about energy densities until the cows come home. The real world is telling us a much different story.


    "Hydrogen Could Become A $130 Billion U.S. Industry By 2050. Could It Also Cut Emissions?"

    https://www.forbes.com/sites/energyinnovation/2019/10/07/how-hydrogen-could-become-a-130-billion-us-industry-and-cut-emissions-by-2050/


    And let's not forget more applications from the world of reality (as opposed to theory).

    Energy density takes a back seat in trains of the future (and present):

    "German Coradia iLint hydrogen train project wins European Railway Award"

    https://www.railtech.com/rolling-sto...railway-award/


    We also should not forget that hydrogen powered aircraft have already taken to the skies:

    "British Airways Teams Up With Hydrogen Flight Startup ZeroAvia"

    https://www.bloomberg.com/news/artic...artup-zeroavia

    Energy density issues simply don't fly in the face of real products.


    And then are are ships:

    "First wave of ships explore green hydrogen as route to net zero"

    https://www.reuters.com/article/shipping-energy-hydrogen-focus-int/first-wave-of-ships-explore-green-hydrogen-as-route-to-net-zero-idUSKBN27F18U


    So here is what we have in terms of real uses for hydrogen in transport:

    Forklifts
    Cars
    Buses
    Trains
    Planes
    Ships


    It would appear that the issue of energy density is not a consideration for the demise of hydrogen in transportation. Once again, the real world tells the story.


    Last edited by Double Helix; August 18th, 2021 at 12:12 PM.
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    Quote Originally Posted by Double Helix View Post
    It is clearly obvious that density aspects are not an issue
    Not an issue for whom? For an average consumers this is definitely an issue. Biodiesel has 6.2 times energy density that of 700 bar hydrogen. It makes difference for a car owner whether to go at the gas station once a week or almost every day. And this not even talking about the costs and safety issues. The cost of implementing and maintaining infrastructure, for example.
    Last edited by Stanley514; August 19th, 2021 at 06:45 PM.
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    Quote Originally Posted by Stanley514 View Post
    Not an issue for whom? .

    It is clearly not an issue for all the engineers designing all these hydrogen vehicles, planes and ships. There is no other reason why it is being pursued by so many people in so many countries. Energy density is simply not an issue or they would be doing something else.

    I don't even think you are reading any of these links. Your rapid response from my last post is proof enough. All you have in mind is energy density. It appears to be the all and everything for you.

    For those designing hydrogen powered transportation, they don't care because hydrogen is working. Neither do all the people operating them, and building up the infrastructure for it.

    Reality rules.
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  38. #37  
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    [QUOTE=Stanley514;633122]
    Quote Originally Posted by Double Helix View Post
    Quote Originally Posted by Stanley514 View Post
    If there is no "theoretical way" to pack hydrogen to sufficient operational density
    Energy density (MJ/L):
    Biodiesel - 33-35
    Ethanol - 18-21
    Hydrogen (liquid, -250 C) - 8
    Hydrogen (compressed, 700 bars) - 5.6
    How does the energy density look in MJ/kg?
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    [QUOTE=exchemist;633126]
    Quote Originally Posted by Stanley514 View Post
    Quote Originally Posted by Double Helix View Post
    Quote Originally Posted by Stanley514 View Post
    If there is no "theoretical way" to pack hydrogen to sufficient operational density
    Energy density (MJ/L):
    Biodiesel - 33-35
    Ethanol - 18-21
    Hydrogen (liquid, -250 C) - 8
    Hydrogen (compressed, 700 bars) - 5.6
    How does the energy density look in MJ/kg?
    Is it really important for majority of applications? Hydrogen is light but does it make it convenient to use?
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    Quote Originally Posted by Stanley514 View Post
    Is it really important for majority of applications? Hydrogen is light but does it make it convenient to use?
    Hydrogen's demonstrated "proof of concept" renders fuel volume/density issues academic.

    Acceptance of any of these approaches will depend largely on the extent of R & D, effectiveness and ease of use.

    Only time will tell which is the most viable. It seems more than likely that various fuels, batteries and photovoltaics will have significant applications.

    One is compelled to wonder if all of the wildfires burning natural fuels will ultimately render all of these issues academic.
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    Quote Originally Posted by Double Helix View Post
    Hydrogen's demonstrated "proof of concept"
    Biofuel even more so. One more energy carrier which could rival hydrogen is Aluminum. For example Aluminum powder. If I no make mistake, metal-air fuel cells could have efficiency around 80%. Metal–air electrochemical cell - Wikipedia
    But for now Aluminum production technology is an ecological challenge.
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    Two articles from Forbes (1,2) reveal an expanding production and utilization of "green" hydrogen for various applications which are occurring today, and the plans to vastly expand it in the future.

    Quoting from (1) :

    "By 2030 Spain aims to online 4 gigawatts (GW) of hydrogen electrolyzers – devices used to split water (H2O) into hydrogen (H2) and oxygen (O2). If this water electrolysis process is powered by renewable energy sources, the resulting hydrogen is virtually emission-less and therefor ‘green’. However, most hydrogen today is produced from fossil fuels (‘gray hydrogen’) – the most common technique being steam methane reforming (SMR) – which is carbon and methane intensive. So-called ‘blue hydrogen’ is produced solely from natural gas and with associated carbon capture, making it a cleaner alternative to conventional methods."

    "Spain’s ample sunshine and rolling hillsides makes it an ideal candidate for green hydrogen production powered by solar and wind – boasting some 62 GW of estimated renewable energy capacity. Their economy currently consumes 500,000 tons of fossil-fuel derived hydrogen annually in traditional industries including concrete mixing, petroleum refining, and fertilizer production, meaning that green hydrogen production could have an immediate impact on emissions even without transportation applications."

    end quote

    In addition to Spain and many other countries, the biggest hydrogen initiative is in Australia. Quoting again from (1) :

    "Perhaps the most ambitious project so far is the Asian Renewable Energy Hub based in Pilbara, Western Australia. The 6,500 square kilometer wind and solar farm will produce over 50TWh of clean electricity, a large portion of which will power on-site hydrogen and ammonia production for delivery to local and export markets. The $16 billion initiative could see green hydrogen shipments as early as 2027.

    The market for hydrogen mobility is expected to significantly grow over the coming decade, with some estimates as high as a $70 billion by 2030."

    end quote

    There is clearly a major move towards global production of green hydrogen for many applications, in many countries, in order to eliminate nearly all aspects of carbon in energy. A reasonable goal to say the least.

    Quoting from (2):

    "Green hydrogen could supply up to 25% of the world’s energy needs by 2050 and become a US$10 trillion addressable market by 2050, according to Goldman Sachs. A number of countries have recently published national hydrogen strategies, including Australia, Chile, Germany, the EU, Japan, New Zealand, Portugal, Spain and South Korea."

    "Investment in green hydrogen production is set to exceed $1billion a year by 2023 as the costs of both renewable power and electrolyser technology fall and governments introduce supportive policies, according to IHS Markit, which said before the announcement of the Green Hydrogen Catapult that there was already a pipeline of 23GW of electrolysis projects, up from current capacity of just 82MW."

    end quote

    Obviously there are a lot of countries, spending billions of dollars, bringing green hydrogen into the mainstream of energy sources. Perhaps the naysayers need to spend some time reading about these activities. It appears to be the best means of reducing reliance on carbon for nearly all applications where it is currently employed. Hydrogen can be a source of clean power whenever, wherever, and for whatever it is required.


    The Green Hydrogen Revolution Is Now Underway"

    1. https://www.forbes.com/sites/arielco...h=ced387a232c6

    "Green Hydrogen, The Fuel Of The Future, Set For 50-Fold Expansion"

    2. https://www.forbes.com/sites/arielco...h=ced387a232c6
    Last edited by Double Helix; October 1st, 2021 at 06:34 PM.
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    One is compelled to wonder if all of the wildfires burning natural fuels will ultimately render all of these issues academic.
    I don't see the connection. Wildfires add CO2 but plant growth after wildfires takes up CO2. Is there evidence or expectation of an enduring imbalance?

    Obviously there are a lot of countries, spending billions of dollars, bringing green hydrogen into the mainstream of energy sources. Perhaps the naysayers need to spend some time reading about these activities. It appears to be the best means of reducing reliance on carbon for nearly all applications where it is currently employed. Hydrogen can be a source of clean power whenever, wherever, and for whatever it is required.
    I have followed progress on Hydrogen and in my view it still lags the hype by a long way. I haven't come to a naysayer position - if that is what it is - lightly. It doesn't mean I want to obstruct R&D or optimistic investors but outside those critical uses like fertiliser and iron smelting I think it will struggle to thrive. Whilst there are some big long term investments in developing Hydrogen there are much larger and much nearer term investments in the technologies that Hydrogen will have to compete against. Battery electric vehicle production is gathering pace amongst the world's biggest auto manufacturers. Nothing hypothetical about their clear choice to gear up for EV's whilst leaving Hydrogen vehicles on the back burner.
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    Quote Originally Posted by Ken Fabos View Post
    One is compelled to wonder if all of the wildfires burning natural fuels will ultimately render all of these issues academic.
    I don't see the connection. Wildfires add CO2 but plant growth after wildfires takes up CO2. Is there evidence or expectation of an enduring imbalance?

    Obviously there are a lot of countries, spending billions of dollars, bringing green hydrogen into the mainstream of energy sources. Perhaps the naysayers need to spend some time reading about these activities. It appears to be the best means of reducing reliance on carbon for nearly all applications where it is currently employed. Hydrogen can be a source of clean power whenever, wherever, and for whatever it is required.
    I have followed progress on Hydrogen and in my view it still lags the hype by a long way. I haven't come to a naysayer position - if that is what it is - lightly. It doesn't mean I want to obstruct R&D or optimistic investors but outside those critical uses like fertiliser and iron smelting I think it will struggle to thrive. Whilst there are some big long term investments in developing Hydrogen there are much larger and much nearer term investments in the technologies that Hydrogen will have to compete against. Battery electric vehicle production is gathering pace amongst the world's biggest auto manufacturers. Nothing hypothetical about their clear choice to gear up for EV's whilst leaving Hydrogen vehicles on the back burner.

    Areas of burning vegetation are burning mostly due to drought, or global warming in the arctic. It seems unlikely that such areas are going to regrow anytime soon, which could represent an increasing desertification for the planet, further driving up CO2 levels as the bio-sink from plants continues to decline.*

    The ease and use of hydrogen is likely to make it the primary source for energy in nearly all applications. Existing engines, with future designs, and fuel cell/electric motors/grids, all run on hydrogen, can produce nearly all the transport and electrification required for the entire world, in addition to solar and wind farms.

    The future of batteries in all this remains to be seen, as does hydrogen, and the planet itself.


    "Anthropogenic climate change has driven over 5 million km2 of drylands towards desertification"

    * https://www.nature.com/articles/s41467-020-17710-7
    Last edited by Double Helix; October 4th, 2021 at 12:25 PM.
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