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There has been much discussion about using hydrogen as fuel for vehicles. Albeit, I don't know much about that type of system other than it's a clean source.

Does anyone have a link or a reliable source that could provide fuel economy numbers for a hydrogen powered vehicle? I'd like to know what the difference would be in terms of fuel economy for an average family sedan running on hydrogen versus gasoline and what sorts of performance differences one might expect.

Thanks folks.
 

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If you do a search for "hydrogen" in the search section you can get quite a information regarding hydrogen. You will find projections about fuel milage and range. Here are a few thoughts I posted about hydrogen in response to GM suggesting to China to start building out a hydrogen infrastructure:

I think it’s a bad idea to pitch hydrogen to China. Firstly, if you tell them hydrogen is the way to go then why should they bother with plug-in hybrid technology? They should just do what they’re doing now and wait for 10 years for the hydrogen technology to become affordable. Secondly, I feel the best path for them is to use a PHEV running a diesel engine. This way they can easily convert to biodiesel and slowly get rid of the diesel and eventually move to pure EV when the battery technology catch up. Does anyone really think hydrogen technology will advance faster than battery technology?

We should do the same here is the US only have flexibility on the range extender. Hummm, that is what we ARE doing. Why, because it makes sense to do so. Are we out building hydrogen infrastructure? No. Sure they have no infrastructure in some areas but can they really afford to move to hydrogen now? No. If the area was making money they would already have gas stations. Right? Hydrogen technology commands the highest prices when compared to other alternative technologies.

If they are going to build out infrastructure it should be in smart-charging ports at parking lots. Hydrogen will probably never make it for personal transportation due to the wasted steps and efficiency losses when compared to advanced batteries. However, even if hydrogen is used for some applications the charging ports will never be wasted. We can assume that the hydrogen cars will have some plug-in capability because grid electricity will always (ALWAYS) be cheaper than hydrogen.

If they do decide to build out hydrogen stations they should do it on the highways only. Hydrogen may turn out to be a good idea for heavy transport trucks because although it takes up 4 times the volume of diesel, hydrogen has 3 times the energy content by weight. Weight is one of the most important factors for cargo transportation.

I think companies should stop pushing hydrogen until there is at least one practical car built. The new Honda is beautiful but I would like to know how it performs in all conditions, how much it costs to operate (cost of hydrogen compared to just electricity), and a good estimate for the cost of the hydrogen systems (assuming they are mass produced). I feel when that is done the pure EV (with quick charge battery technology) will seem light years ahead.

People are concerned about the procedure to rapidly charge EVs. The answer is very simple. You have quick-charge stations with advanced batteries. The batteries are charged up all day and night (so no huge substation needs to be built). When a car comes to be charged direct battery-to-battery inductive charging is utilized. It will be quick, safe, extremely efficient. The whole system has almost no moving parts at all. Project Better Place proposes the swap-out station. This will also work well and those stations can eventually be converted to quick-charge stations. They will already have the underground storage for the batteries so modification should be fairly simple. If the swap-out station was designed from the start for that eventual conversion then even better.

If they set their minds to building hydrogen stations they should not spend too much effort in the supply infrastructure. Use natural gas CH4 for now and then move to advanced hydrolizers, should the new technology make it out of the lab. Building out huge hydrogen factories and the massive amount of liquid hydrogen transport trucks would be extremely costly and I believe ultimately wasteful.
After 5 years a much better analysis can be made regarding the full scale build out of hydrogen infrastructure. It’s my believe that 5 years from now battery technology will look many times better than fuel cell technology. Let’s face the facts. Hydrogen production is inefficient, very difficult to store and requires vastly different and expensive infrastructure. It also ties people to another liquid fuel. Home charging will be more difficult compared to home charging an EV. With an EV you connect the grid or solar panels to the batteries through a simple charger. No moving parts. No water supply, filters to mess with, complex technology to break down that requires a visit from a specialist. Perhaps it’s just too simple for some interested parties.

Thus, don’t tell the Chinese to go “all out” on hydrogen. Tell them to research it heavily and proceed with caution. Smart charging stations located at every parking spot will always be welcome and will fulfill the private transportation needs of most individuals. A carefully selected range extender (if needed) will fulfill the long travel gaps. Public transportation or long-range vehicle rental would probably be better option there.

Oh, and suggest they make their cars light and small. Get that culture ingrained as soon as possible! Look how hard we have it here in the US putting tiny Smart cars on the roads with Hummers. It’s probably going to take us 20 years to get those beasts off the roads. If ever! There seems to be trend to just make very large AND green vehicles. When you calculate the amount of energy that actually moves the person it’s quite embarrassing. However, as long as it’s sustainable and we remain competitive in the global marketplace then maybe we can afford that luxury, along with our McHouses.
 

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why hydrogen will not be the fuel of the future

I know a lot of people a lot smarter than me are convinced it will be the fuel of the future, but every time I look at the numbers, it just doesn't add up.

From what I've seen, there are two viable ways to get hydrogen now. Convert natural gas or use electrolysis.

Here's what my calcs tell me about the viability of converting natural gas:
ASSUMPTIONS
· Hydrogen in the near-term future will be produced by re-forming natural gas (CH4) into H2.
· The conversion process is 80% efficient.
· 1 kg natural gas creates 0.25 kg H2
· Current US gasoline consumption = 8,700,000 barrels/day (per EIA data)
· Through improved vehicle efficiencies and less driving, gas consumption can be cut in half.
· Fuel cell vehicle net efficiency to shaft = 60%. (optimistic!)
· ICE net efficiency = 25%.
· Gasoline heating value = 5,460,000 BTU/barrel
· Natural gas heating value = 1052 BTU/ cubic foot = 54 MJ/kg
· H2 heating value = 143 MJ/kg
· Current US natural consumption = 66 billion cubic feet/day


CALCULATIONS – (convert everything into gasoline bpd equivalent)
· Current net required shaft energy @ 25% ICE efficiency = 8,700,00 bpd * 0.25 = 2,175,000 bpd equivalent
· Post efficiency improvement shaft energy = Current/2 = 1,087,500 bpd equivalent
· Required H2 energy at 60% fuel-cell efficiency = 1,087,500/0.6 = 1,812,500 bpd equivalent.
· To make one bpd equivalent of H2, it will take (54/143)/(0.25*0.8) = 1.89 bpd equivalent of natural gas. (H2 has a much higher energy density per kg, but It takes 4 kg NG to make 1 kg of H2. The conversion efficiency is 80%)
· Required natural gas energy to make H2 for all vehicles = 1,812,500 bpd*1.89 = 3,422,600 bpd equivalent.
· Convert barrels gasoline to cubic feet Natural gas - 1 barrel = 5,460,000/1,052 = 5,190 cubic feet.
· One billion cubic feet natural gas = 1,052 billion BTU’s
· 1,052 billion BTU/5,460,000 BTU/barrel = 192,673 barrels/billion cubic feet
· Required natural gas/day = 3,422,600 bpd/ 192,673 = 17.8 billion cubic feet/day
· % of current US consumption = = 17.8 billion/66 billion = 27%.

CONCLUSION
We would have to increase our natural gas production and consumption by 27% to switch to hydrogen IF we both double our driving efficiency and greatly improve the efficiency of the current hydrogen reforming process.

QUESTION – where will the gas come from, especially if we increase natural gas power generation so we can phase out coal to reduce greenhouse gas emissions?

Please review my numbers and post any gross errors. This is back-of-the-envelope stuff, so I might have mis-carried a decimal.

When I get time next week, I'll see if I can put together part 2 - how much electricity will it take to make H2 by electrolysis?
 

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Some optimizations possible

Although I also think that hydrogen is not a good idea, there are some optimizations possible, when you make it form electricity.

First use intermitted power. If the whole grid is renewable, than there are moments of surplus of power. Use those moments to generate hydrogen. Then you have also the hydrogen on the place where you need it, transport is avoided.

Or, use HTE (or a chemical equivalent). High Temperature Electrolysis. You can use this technology in a concentrated solar power plant, with a tower design (the temperature in other designs is too low). The thermal input from such plant is much cheaper than the electrical input. Water is heated and electrolysis on heated steam requires less electricity. An Australian company is working on this technology using thermal solar combined with CPV.

Hydrogen economy was envisioned by some people in a nuclear society. If you have nuclear plant with high temperature (current plants are low temperature), you can generate hydrogen with HTE at night on low demand. Breeder reactors would be of this high temperature type. But before these reactors will be available, solar will probably already won the race.

Currently the price of natural gas has to double (or more) before these technologies become competitive.

Lucas
 

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More problems with hydrogen...

Besides the Co2 released and the energy required to liberate hydrogen using steam reforming, there are the transportation, storage and power density issues. Take the the BMW Hydrogen 7. It has a big 6.6 liter V12 pumping out 260hp (the motor produces 360hp in the 750Li and 438hp in the 760Li on gas power density issue), and it gets a whopping 17miles per kilogram of H2. Keep mind that at 5000 psi 1 kg of H2 takes up 20 gallons of volume (greatly reducing the range of the H7). Because BMW is storing the H2 as a liquid (at -253 °Celsius), it can store car a whopping 8kg of H2, this gives the Hydrogen 7 a 120 mile range. Oh, that range is if you keep the hydrogen actively cooled (consuming energy), if not, the liquid hydrogen will evaporate at a rate of about 5% per day. Refrigerating to -253 °C and storing at that temperature is energy intensive, even more so than compressing H2 to 5 or 10 thousand PSI (and taking a range hit). People will argue that a Hydrogen fuel cell vehicle negates these issues. It will waste less of the energy stored in the hydrogen, but isn't nearly as efficient as battery to electric motor drivetrain. And you still waste the energy used to make, compress, transport, store, cool and deliver the H2.

Hydrogen sounds cool, but doesn't make any sense in a daily driver. That is unless you own a well that is producing the natural gas that hydrogen is being reformed from. Lots of money to be made getting people to switch from gas to hydrogen. Not nearly as much an upside for those same companies if EREVs or BEV's replace gas vehicles. The electricity distribution system is efficient, and already exists (unlike hydrogen refueling stations, lots of money to be made (wasted) building those too), and the EREV or BEV produces no emissions, unlike the Hydrogen 7.
 

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You are not alone hvacman. Not many people are smarter than Ulf Bossel and here's what he had to say about the hydrogen economy (see link below). It caused an uproar in the hydrogen economy circles and I don't think they ever recovered. This analysis is a must read if you have even the slightest interest in using hydrogen for transportation:

http://www.efcf.com/reports/E21.pdf

"Electricity obtained from hydrogen fuel cells appears to be four times as expensive as electricity drawn from the electrical transmission grid."

Ul f B o s s e l


That should be the first thing you think of when you are working on hydrogen projects. Also, in terms of energy content liquid hydrogen has 4 times the volume of gasoline but it weights 3 times less! This substance is incredibly light but extremely hard to hold on to. We will just have to wait and see what people come up with. It could be used for airplanes, heavy transport, shipping and possibly even personal transportation. However, I'm betting that EVs will be cheaper, safer and more reliable for the everyday Joe.
 

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well-to-wheel efficiency

Texas, thanks for digging up Ulf's article. I was digging for it when I ran my own quick numbers, but couldn't quite put my Internet fingers on it. "Well-to-wheel efficiency" (W2W) is the key phrase to describe the concepts in Ulf's article.This basically is the concept of calculating the net energy available as shaft HP at the wheel as compared to the total energy content of the original energy source (not of the storage medium). Natural-gas reforming to make hydrogen is a disasterous concept for a lot of reasons, but electrolysis makes even less sense.

For our transporation energy future, we have several often-conflicting criteria to consider for our energy storage systems. including several energy density issues:

energy density per $
energy density per kg
energy density per liter

Hydrogen, when viewed through these energy-density-based rose-colored-glasses, can be made to look pretty darn attractive compared to electro-chemical energy storage. Hydrogen advocacy and official government policy is largely based on this filtered vision. Just read any promo for H2 and you'll see it.

But if we ultimately will be relying on renewable sources like PV and wind, which have high per-kW and huge per-kWh capital costs, W2W efficiency will trump energy density as the prime factor. As Ulf and others have shown, electrolytically-produced H2 will have a W2W efficiency of about 20% net, IF some breakthroughs are achieved to improve fuel-cell efficiencies. Here's a link to an opinion column I wrote last year that translated Ulf's calculations in 750 layman's words:

http://www.redding.com/news/2007/aug/26/the-hydrogen-economy-its-nothing-but-hot-air/

(OK, high temperature electrolysis (HTE) at a nuclear reactor will reduce the electrolysis energy, but all the other system losses remain, still killing the W2W efficiency. Plus, we are talking nuclear - is this a good plan?)

Current Li battery technology sees about an 80% W2W efficiency (95% charger efficiency x 90% charge efficiency x 90% discharge efficiency). Flywheel technology, at 90%, is about the only other energy storage concept that exceeds this W2W efficiency. The current vision is that flywheels are not good candidates for delivering low power outputs for hours at a time.

Despite the painfully low energy density for current-generation LI battery packs, it is by far the most energy-efficient energy storage system available now or projected to be available on the foreseeable future. It is far more likely that the battery engineers will upgrade energy densities and reduce costs faster and more simply than the hydrogen engineers can improve their W2W efficiencies. Once battery designers get a reasonably-priced and sized battery that can carry a well-engineered 4-5 passenger car 300-400 miles, the energy storage debate will be over. Batteries will have proven to be "good-enough".

My prediction - the energy density battle will demonstrate once again the old engineering adage that practical "good-enough" beats theoretical "optimal" every time.
 

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I thought about this the other day. If we go with battery technology in cars today, future cars will only get cheaper, lighter, blah blah blah. The following thought really struck me... Unlike the current situation we are in where the cost of gas will only go up and up as the world demands more oil but less is available due to inevitable peak oil the real cost of EVs will feel like the price of gas is going down and down as we slide along the battery technology curve.

Certainly that future reduction of risk has have some value. It's the same with solar panels. It might be a bit more expensive at first but you are guaranteed those costs for the next 25 years. Knowing the costs that far out makes it easy for financial decision making. Additionally, the replacement costs of the panels will only go down. One more time because I feel this is so important... The cost of energy for EVs will get less expensive as time goes on (solar cells directly feeding batteries). What can you say about the price of gas in 10 years? Yeah, I have no idea either. People will say that a lithium shortage will cause problems but there are so many different technologies in the works that I doubt we will be locked to one formula, like we are with gasoline.

I honestly can't be sure that buying a Tesla is not the best financial move you could ever make. If gas prices in the future not only cost $20 bucks a gallon but you can only get it after sitting in line for 10 hours that Tesla is going to look quite sweet. The Volt too! With the Volt you might not be able to go on long trips but you will be tooling around town with no problems at all, accept for dealing with people trying to steal it. ;)

With a hydrogen system however I'm not sure about future cost reductions. The fact that there are so many mechanical considerations including high pressure pumps, 10,000 psi high volume pressure vessels, chemical processes that include combining forced air and pressurized hydrogen together in a pressure resistant container (fuel cell) leads me to believe that the fuel cell system will never achieve the simplicity and cost reductions that battery technology will. However, for special applications hydrogen's many advantages like very high power to weight ratio may be useful despite the complexities in containing such a light gas or the inefficiencies of it's conversion process.
 

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I pointed out this company in another thread, but since this one is about hydrogen I'll post it here. Here are a couple of links to the companies website:

http://www.millenniumcell.com/fw/main/How_it_Works-31.html

http://www.millenniumcell.com/fw/main/Overview-27.html

They use a sodium borohydride solution to store the hydrogen. There is a solid blend that can be shipped by air. That would alleviate some of the initial infrastructure demands. Just think, you could pay for a monthly service like netflix where you pay for a certain amount of fuel in advance and it is shipped straight to your home and then you recycle the resultant Sodium metaborate.

Looks like chrysler looked at the Millennium Cell systems back in the day before the Daimler take over, but it was ended after the take over. Too bad.

http://www.allpar.com/corporate/fuel-cells.html

Ah well...
 

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I've no doubt that hydrogen will be cheap to generate and store, given the recent breakthroughs in those respective techs. Here are two companies making progress:

Quantum Tech Link

Quantum Sphere Link

Fortunately, all the effort going into EV's and hybrids just pave the way for fuel cell vehicles, as they can be grafted into either of these systems as a range extender.
 

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CONCLUSION
We would have to increase our natural gas production and consumption by 27% to switch to hydrogen IF we both double our driving efficiency and greatly improve the efficiency of the current hydrogen reforming process.

QUESTION – where will the gas come from, especially if we increase natural gas power generation so we can phase out coal to reduce greenhouse gas emissions?

Please review my numbers and post any gross errors. This is back-of-the-envelope stuff, so I might have mis-carried a decimal.

When I get time next week, I'll see if I can put together part 2 - how much electricity will it take to make H2 by electrolysis?
Ahh...HVACMAN...shack! Natural gas is the quickest/easiest way to produce hydrogen...but where are we going to get all that natural gas from? I can't help but find it ironic that in the same breath you dismiss coal. Have you ever heard of a methanogen? Funny how everyone assumes the only thing you can do with coal is combust it and contribute to global warming. Paradigms are hard to break.

Here is ONE possibility. Read the brochure and applications at the link below.

http://www.arctech.com/micgas.htm

The real potential with the above technology is in situ application. Translation – we can engineer man made natural gas fields in the 5.6trillion tons of unmineable coal in the United States alone.
 

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Nothing is simpler than Battery and Electric Motors

Anyone voicing rejoice for a Hydrogen economy for any reason must work for Big Oil or the government. I'll take my one time purchase of a bev AND RECHARGE AT HOME AND NOT RELY ON ANYONE TO SELL ME DAMN FUEL TO RUN A REAL
STUPID HYDROGEN BATTERY POWERED ELECTRIC CAR. SOME PEOPLE ON HERE SOUND LIKE YOU JUST WANT TO GIVE AWAY YOUR HARD EARNED MONEY TO SOMEONE ELSE FOR NO GOOD REASONS, GIVE IT TO ME THEN IF YOU SO EAGER.
 

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Read the information found at link above...before you summarily dismiss it. What is the harm in at least learning about the technology? It is but one possibility. Then you can at least dismiss it based on a rudimentary knowledge rather than a conspiracy theory.
 

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I want there to be a choice between electricity and hydrogen, so that no one vendor can maintain high prices. Right now, we have gasoline, diesel and ethanol, each doing its part to prevent the others from getting to high above the others.

Hydrogen can be produced, even from water, without electricity, as there are solar hydrogen generators that use sunlight directly to dissociate water molecules, so don't waste time flapping your gums over hydrogen's cost being driven by electricity.
 

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Read the information found at link above...before you summarily dismiss it. What is the harm in at least learning about the technology? It is but one possibility. Then you can at least dismiss it based on a rudimentary knowledge rather than a conspiracy theory.
Read the article. I hope the science is real and the skeletons in the process are minor. This could be huge step forward. Using the methane in a hydrogen fuel cell, however, sounds like a waste of perfectly good methane.
 

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Your Chance is here now to be Free, dont blow it!

For the first time in a hundred years we as Americans have the true blue chance of being totally independent of big oil.
You can go with a BEV which is so simple it dosen't need any discussion or you can go with the governments plan of converting something to make hydrogen to power your car at a price you will pay for every single day just like gas. Do you want to be tied to some fat cats for the next hundred years to supply your cars with fuel or just buy you some solar panels for home use to charge your car like I did. I will be independent of all future monopolies and government bs or big oil bs. Some say give hydrogen a chance, well you are really saying hey give some one else the chance to control your life and your money, like whats been going on for the last century with gas.
Tesla had the right idea in the early 1900's with his invention of AC electric current, motors and car . You can thank him for everything you have now today, he is the true father of electricity as we know it today. Everything else in our lives we have runs on electricity but our autos. Also some Hydrogen people are saying well BEV's will make the grid pollute more from coal use, well if so stop eating then and turn off your 220v ovens that cooks your chicken casseroles for 2 hours every night.
 

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jeremy,

You can generate your own hydrogen directly from the sun, no electricity needed:

Nanoptek Home

... and Quantum is developing the compression system:

Quantum / Boeing Partnership

Batteries are very expensive, but GM is already planning a fuel cell Volt for production. True, if you have $100K to burn, then buy a Tesla, sit around for 4 hours until is charges, drive 200 miles, then repeat. I would prefer a fuel cell Volt that I could refuel in 5 mins from my Quantum storage tank full of hydrogen I generated from my Nanoptek hydrogen generator.
 

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Practical Quick-charge BEVs vs. Practical Hydrogen vehicles


Who will get there first? Place your bets!
Neither, unless you count 25KWh/hr ubiquitously available charging as quick charging. Jason's Tesla owning freind will be tooling around in 400 mile $75K car by the time these developmental contracts actually develop a marketable product to find there is little market demand. Save the $, kill the pork, reduce the debt.
 
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