Hydrogen Economy?

[Sunking]

There is a lot of talk and hype about a Hydrogen Economy with all the concern and politics of global warming. At best it is wishful thinking, at worse deceptive and dishonest..

There are many problems with hydrogen fuel cells, most of which are engineering problems that can probable be solved if time and money are of no importance. But there is one problem that can never be solved, and that is free hydrogen is not a source of energy, it is a carrier of energy.

Free hydrogen does not exist on this planet. It is all bonded to other molecule like oxygen to make water or in hydrocarbons like natural gas and petroleum. Basic physical laws tell us it takes more energy to break these molecular bonds, than to form a bond. It is the Second Law of Thermodynamics, and there is no way around it. Scientist have been working for decades trying to find a catalyst to lower the energy requirement to make hydrogen, but it will never be unity. Best hope is well to wheel efficiency is 50%..

All free hydrogen today used for any commercial or industrial use is all made from Natural Gas. So right from the start you are still dependent on fossil fuel to make it. To make hydrogen from NG you burn NG to make steam from water then the steam is used to strip the hydrogen from the methane bond. So what you do is input 10 units of energy from NG to get 4 units out, or 40% efficiency. So you can clearly see the problem there. You are better off just using the natural gas and burning in an engine or a boiler. But here is the real killer. Hydrogen made from NG will always be a multiple of the NG, and have to compete with the very fuel it is made from. So much for NG.

Ah, but I know what you are thinking, hydrogen can be made from water with the electrolysis process using solar and wind power. Well that is the wishful thinking part and what politicians would like you to believe as they poor billions of your dollars into a bottomless pit.

Here is the first problem; electrolysis is less efficient than steam fracturing with NG, around 25% efficient from air to wheel. Even with the advances in PV technology today would take enormous amounts of land covering the Midwest plains, so much for agriculture and food. OK you can cover the whole desert southwest, no one will miss that right? Well how do you plan to get the water there? At current fuel demands you are talking about routing 10% of the Mississippi river flow to processing plants. No problem. Now for the big problem. Like NG the demand for the electric power will have to compete with hydrogen production, and always be a multiple. So much for RE sources.

The only way to realistically and economically method to produce hydrogen is with nuclear energy by using the excess heat and generation capacity. In the USA it would take an additional 900 nuclear reactors to meet current transportation needs. Even though it is the most economical method to produce hydrogen, at current technology and prices to make an equivalent amount of hydrogen to equal 15 gallons of gasoline is $400. How does that sound?

Well enough of the production problems, that is the easy and inexpensive part. Now let

[russ]

Hi Sunking, A good and informative post about hydrogen.

A couple of additions I would like to make (this was the stuff I worked with for many years).

1) Hydrogen embrittlement - Generally a problem at high temperatures and high pressures - that is the reason behind developing an engine for it. At low temperatures it is not really a problem.

2) H2, being lighter than air, rises upon release. If it has a free path then it is up and gone but an unventilated space such as in the top of a garage it could collect. If the garage was vented at the highest point then no problem. Any spark and static electricity is perfectly adequate can ignite it. This should always be a consideration when locating batteries.

3) I would consider a hydrogen storage vessel as safer than any car's gas tank - gasoline is dangerous! For any fuel (or energy carrier) to burn or explode it requires air. When the concentration of fuel & air reach a certain point the mix is flammable and in higher concentrations are explosive - flammable comes first. The cylinders for burning torches in many home shops are more dangerous.

4) As you pointed out - there is no manner available today to generate H2 economically so the whole thing is a moot point I suppose. You pointed out the difficulties in doing so quite nicely. Reforming natural gas or other hydrocarbons is dirty environmentally as well.

5) People that want to 'crack' CO2 for use as C + O have the same energy problem - sure it can be done and how to do it is well known. However, it is horribly energy negative and consequently a dumb idea. Universities are working on many things but they are all 20 years and more away.

[Sunking]

Hey Russ thanks. I am no metallurgist or Mechanical Engineer by any means but everything I have read upon Hydrogen Embrittlement indicates the reaction happens at all temps. I do read it is accelerated by elevated temps, but occurs at even room temp.. One such source with a quick search reads like this:

The mechanism starts with lone hydrogen atoms diffusing through the metal. At high temperatures, the elevated solubility of hydrogen allows hydrogen to diffuse into the metal (or the hydrogen can diffuse in at a low temperature, assisted by a concentration gradient). When these hydrogen atoms re-combine in minuscule voids of the metal matrix to form hydrogen molecules, they create pressure from inside the cavity they are in. This pressure can increase to levels where the metal has reduced ductility and tensile strength up to the point where it cracks open (hydrogen induced cracking, or HIC). High-strength and low-alloy steels, nickel and titanium alloys are most susceptible. Austempered iron is also susceptible

What I am picking up on is the concentration gradient of a containment vessel like a high tensile strength steel cylinder that is required to be used to handle the extreme high pressures of 10,000 PSI. Other than liquid form I am not sure how much higher concentration one can get. I was certainly not making it up as about every scientific paper written on the Hydrogen Economy brings this up as a major obstacles, and the research being done to find an alloy to overcome the problem.

But as you said it is a moot point because no matter what, the bottom line is hydrogen gas will always by a multiple in price and in competition with its fuel source to produce it. That is a point advocates never want to discuss or bring up.

[russ]

Hi Sunking, The hydrogen embrittlement topic is much talked about by people a lot smarter than I. My experience is at relatively low pressures of between 2 and 40 barg and temperatures of up to 1250 deg C. The gas was typically 55% H2. We would be recirculating about 250,000 NCMH in one of the new plants - we would consume around 75,000 SMCH of natural gas per hour in the same plant - enough for heating a good sized city on a cold day.

H2 embrittlement was never a source of problems in the plants under those conditions. We never replaced one kg of steel duct, furnace plate or even reformer tube due to that problem.

With chemical processes a smart process engineer will quickly admit they have a reasonable idea of what is happening and with things like reforming of CH4 maybe even 50% of what happens. The balance just happens. There are so many considerations of pressure and temperature plus constantly changing pressures and temperatures that you don't really know what is happening on a molecular basis.

The not so smart types will claim they understand it all but like I said, the really good engineers understand and admit they are making a SWAG in many cases.

Trying to store any gas is not cheap and H2 is worst case ++. LNG (5 years back) was maybe 25 US cents per SMC at the well head and 3.50 USD delivered. The big cost was making it cold and liquid plus the special ships to transport it.

It would be wonderful to have hydrogen available - burns clean, non toxic etc but maybe some day - certainly not now regardless of what many green sites chatter about. There are many breakthroughs needed to make a H2 economy real!

[Sunking]

It would be wonderful to have hydrogen available - burns clean, non toxic etc but maybe some day - certainly not now regardless of what many green sites chatter about. There are many breakthroughs needed to make a H2 economy real!

Russ I am no authority on Hydrogen Embrittlement. I do know Ford and Chrysler both worked on hydrogen internal combustion engines in the 80's and gave up because they could not find an allow for the blocks and heads that did not crack in a few short thousand mile test.

But like I said, it is a moot point, a hydrogen economy cannot work. It is pretty simple when you think about it and answer a few simple questions like.

I can buy a Kwh of electricity from my wind or solar farm for say 20-cents, or I can buy it for $4 in hydrogen made from the electricity generated at the same solar or PV farm. Which one will I buy? Which business stays in business? The electric company or the hydrogen company? It is really that simple. With a maximum 5% plant to wheel efficiency hydrogen cannot compete with the source fuel or energy used to make it.

Before someone says well the idea is to store it for later use, think again please. Current battery technology is 90% (lithium) efficient at 1/10 the equipment cost. who in their right mind is going to pay 100 times more? Oops I am sorry, the government wants you to do that, my bad.

[russ]

For the motors it is both high temperature and high pressure at the moment of ignition.

The government and all departments are being silly as they try to support Obama's statement about using RE. He has no idea what he is talking about and it seems all below him just wag their head (tail) and say, 'of course sir'! The cabinet secretaries are kissing backside as well as everyone below them - generals and admirals included.

I was reading Green Tech Media a couple of days back where Michael Kannelos was pointing out that bio refineries can be modular and therefore movable for the military. I asked, 'What about the feed stock?'. To date all bio refineries are both uneconomical and highly feed stock specific.

Year back at a plant I worked at we had access to natural gas that was being flared at certain hours due to lack of demand. We did a study as to the practicality of capturing that gas for our later use - the answer was zero practicality. For the volumes we would need to do in order to be practical gaseous storage was out and making LNG out of it was totally impractical due to capital cost - not to mention operating cost.

[wjgrisham]

[QUOTE=Sunking;12902]There is a lot of talk and hype about a Hydrogen Economy with all the concern and politics of global warming. At best it is wishful thinking, at worse deceptive and dishonest..

There are many problems with hydrogen fuel cells, most of which are engineering problems that can probable be solved if time and money are of no importance. But there is one problem that can never be solved, and that is free hydrogen is not a source of energy, it is a carrier of energy.

Free hydrogen does not exist on this planet. It is all bonded to other molecule like oxygen to make water or in hydrocarbons like natural gas and petroleum. Basic physical laws tell us it takes more energy to break these molecular bonds, than to form a bond. It is the Second Law of Thermodynamics, and there is no way around it. Scientist have been working for decades trying to find a catalyst to lower the energy requirement to make hydrogen, but it will never be unity. Best hope is well to wheel efficiency is 50%..

All free hydrogen today used for any commercial or industrial use is all made from Natural Gas. So right from the start you are still dependent on fossil fuel to make it. To make hydrogen from NG you burn NG to make steam from water then the steam is used to strip the hydrogen from the methane bond. So what you do is input 10 units of energy from NG to get 4 units out, or 40% efficiency. So you can clearly see the problem there. You are better off just using the natural gas and burning in an engine or a boiler. But here is the real killer. Hydrogen made from NG will always be a multiple of the NG, and have to compete with the very fuel it is made from. So much for NG.

Ah, but I know what you are thinking, hydrogen can be made from water with the electrolysis process using solar and wind power. Well that is the wishful thinking part and what politicians would like you to believe as they poor billions of your dollars into a bottomless pit.

Here is the first problem; electrolysis is less efficient than steam fracturing with NG, around 25% efficient from air to wheel. Even with the advances in PV technology today would take enormous amounts of land covering the Midwest plains, so much for agriculture and food. OK you can cover the whole desert southwest, no one will miss that right? Well how do you plan to get the water there? At current fuel demands you are talking about routing 10% of the Mississippi river flow to processing plants. No problem. Now for the big problem. Like NG the demand for the electric power will have to compete with hydrogen production, and always be a multiple. So much for RE sources.

The only way to realistically and economically method to produce hydrogen is with nuclear energy by using the excess heat and generation capacity. In the USA it would take an additional 900 nuclear reactors to meet current transportation needs. Even though it is the most economical method to produce hydrogen, at current technology and prices to make an equivalent amount of hydrogen to equal 15 gallons of gasoline is $400. How does that sound?

Well enough of the production problems, that is the easy and inexpensive part. Now let

[thegreenman]

We certainly need some way to store solar energy and I think hydrogen although wit hit's problems is the only cost effective and practical solution long term.

I did read somewhere about using solar to compress air then using the air at night to generate electricity.

I really can't see the current (no pun intended) battery technology being a practical large scale solution.

[russ]

Hi Greenman - You may have read about hydrogen but please keep reading. You will find any potential methods to generate it are still in the university labs - if they even work - and would be 10 to 20 years away from being commercial.
Electrolysis is a very energy intensive act - you would end up building 2 or 3 times as much solar to do so. Storage of H2 is also tricky.

There is talk of compressed air storage and it is even being tried at present but the usefulness is limited - if it functions as advertised.

[thegreenman]

Ironically nature already does a great job of turning sunlight into stored energy with photosynthesis.

As for hydrogen although it is currently an energy intensive process the way I see it is that any unused solar energy is better stored then not used assuming the power is not fed back to the grid.

[russ]

You drive up the cost of the solar installation by 2 to 3 times - I don't know the exact figure offhand. That is to overcome the losses of electrolysis, compression, storage and delivery.

You can see in Sunkings post the part about 21 tankers of H2 being required to deliver the equivalent of 1 gasoline tanker.

[Sunking]

Ironically nature already does a great job of turning sunlight into stored energy with photosynthesis.

Well photosynthesis stlll falls way way to short in terms of energy density by volumetric measures and is the reason why ethanol or other bio fuel not work as transportation fuel. If we converted all arable land for biofuels would only meet 25 to 30% of out fuel needs and leave us nothing to eat. The most dense form of sunlight energy is fossil fuels.

As for hydrogen although it is currently an energy intensive process the way I see it is that any unused solar energy is better stored then not used assuming the power is not fed back to the grid.

Well as I said in the beginning a Hydrogen economy at best is either wishful thinking, or dishonest and misleading. I think you are in the Wishful Thinking camp. But think about a few things.

Volumetric Density

Hydrogen energy volume at 150 Bars (gas compressed to 10,000 PSI) is 405 wh/liter. Compare that to today's LiFePO4 battery at 1100 wh/liter. I assume you know what that really means? It would take about 3 times the volume of hydrogen to equal that of a battery for a given amount of energy.

Efficiency
Right now with today's technology a LiFePO4 battery efficiency is above 90% with less than 1% self discharge in a month. Today making hydrogen with electricity and water plant to wheel is less than 5% coupled with 1.7% loss per day. That is the final nail in the coffin.

You have to keep in mind hydrogen will always be in competition with its source fuel. I do not care what that source is. So if your source fuel is solar, and let's say the kwh production cost is 20 cents/kwh, to convert it to hydrogen, a Kwh of hydrogen production cost with 5% efficiency is $4.00/Kwh and retail for about $5.00 Kwh. Using Lithium batteries at 90% efficiency would cost $0.23/kwh to produce and retail around $0.30/Kwh. Now tell me as John Doe consumer which product are you going to buy? Will you pay $0.30/Kwh or $5.00/Kwh? Who remains in business and who goes out of business?

Today we have all the technology we need for complete domestic production of all energy right here in the USA. It is clean and we have over 1 million years of fuel that will generate high paying jobs and make us very competitive in a global market. The answer is nuclear power plant and Electric Vehicle light transportation fleet. Medium and heavy transportation will always require a fuel as dense as diesel, there is no way around that fact.

[thegreenman]

I must admit I am in the dark about Lithium Iron Phosphate batteries but was comparing to the standard lead acid batteries many enthusiast diy solar kits use.

Yes, I guess I am in the wishful thinking camp and realise nuclear will play a major part in our power generation with both fusion and fission.

To clear up the point about photosynthesis I was just comparing natures ability to store energy. Oil is after all the suns energy compressed.

I do think the idea of biofuel as laughable and think we are wasting our money on methodologies that can never succeed.

Sunking you do seem to be very knowledgeable are you by any chance a scientist working on developing power sources?

[russ]

Sunking a scientist? Don't think so - just an experienced and well educated engineer.

We all appreciate the experience of both Sunking and Mike!

[Sunking]

I must admit I am in the dark about Lithium Iron Phosphate batteries but was comparing to the standard lead acid batteries many enthusiast diy solar kits use.

That is understandable as most of the public is unaware of battery technology advancement. Under the pretense of lead acid technology, hydrogen economy would be feasible as lead acid batteries have very low energy densities on the order of 50 wh/kg and a life span of 2 to 7 years.

However LFP has made revolutionary advances in the last 10 years. A123 Systems already has a commercial product out for the EV industry with a density of 240 wh/kg, 10,000 cycle life to 80% capacity, and 5C charge and discharge rates. Now that may not mean a lot to you and others but what it means is you can have a mid sized electric car with all the Bells and Whistles we are accustomed to, 300 mile range. can be fast charged in 15 to 20 minutes. last 30 years, and at today's electric prices with 200 wh/mile efficiency a 3 cents per mile fuel cost. It is here today and you can buy it right now.

Yes, I guess I am in the wishful thinking camp and realise nuclear will play a major part in our power generation with both fusion and fission.

Well I am confident we will have fusion reactors before we have a working Hydrogen Economy model. For now we have fission, and today's Pebble Breather Reactors are passively fail safe and not the WWII technology the fear mongers use to scare people with. Spent fuel rod storage is a man-made political problem that can be solved with a stroke of a pen by Presidential Executive order that made it in the first place by POTUS Gerald Ford. There is no reason to store spent rods, they are like aluminum cans you recycle them and reuse the fuel. I guess it never occurs to the American public why such small countries like France, Sweden, and Japan have no problem with spent fuel rods.

Once we have fusion reactors the game is up, all energy problems are solved until man is extinct. We will have an over abundance of dirt cheap clean energy that is inexhaustible. The best educated guess is 10 to 15 years for a working prototype, then another 20 to 30 years from that point to deployment. This is where our tax dollars should be going instead of wasting it chasing fruitless adventures.

Sunking you do seem to be very knowledgeable are you by any chance a scientist working on developing power sources?

No, no, no. It would require a couple more years of school and a pay-cut to earn a Phd I have a Master of Science in Electrical Engineering and Professional Engineering Licensure in TX, OK, NM, and AZ. I spent my first 10 years working for a electric utility in TX & OK, then another 10 years in the Telecom sector as a Power Protection Engineer until the bust in 2001, now I own and operate my own Design-Build firm doing what I did for the utilities and telephone companies 20 years ago for a lot more money on my terms. Never had any desire to be a scientist as they do not get paid very much and have to rely too much on Government grants for work. To make the big bucks as a scientist requires you work for some private company like Gruman or Lockhead which is still tied the Uncle Sam.