Hydrogen and FCEVs discussion thread

Musk's article has already been linked. I'm a fan, but that doesn't make him perfect. This, for example, appears to be quite wrong:

Musk goes on to state that even given the very best hydrogen technology, it doesn’t come close to the energy density of a modern lithium-ion battery pack like that found in the Model S.

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We had fuel cells with twice the energy density of lithium in 2005, and equipment on the bench today has about eight times the energy density.
http://news.softpedia.com/news/Fuel...nergy-Density-of-Lithium-Batteries-6787.shtml
http://www.parc.com/content/attachments/fuelcells_arpa-e_parc.pdf
Horizon Fuel Cell Aeropak - airborne fuel cells exceed 800Wh/kg
http://www.horizonfuelcell.com/#!copy-of-aerospace-solutions/ccm4



It appears that he, like many here, are looking at only the personal car slice of the picture. I'm not surprised, considering this is an EV forum and most of you are fairly well educated - by a system that's concentrated for more than 100 years on taking things apart to examine progressively smaller pieces.

In case some haven't groked fully yet, we have a serious problem on this planet and we simply don't have time for painfully slow evolutionary processes. We need people that can see things from a systems perspective - from a big picture - and that can take the required steps to help us out of the hole we're in.

Most world leaders that understand this are 'terrified' according to Rifkin, who's been advising many of them for more than 10 years and is the architect of the plan that basically kept Germany out of the worldwide recession that we're still wallowing in. Their ability to understand the reality of the situation we're in is what's motivating far-right conservatives to work with socialists.

This is the most progressive group I've yet seen. If you folks can't wrap your minds around this, I'm not sure there's hope for our country. And that terrifies me.

Musk's "energy density" reference seemed doubtful, and I wonder what he really meant by that. The chart you posted looks more like what I'd expect.

AndyH said:

It appears that he, like many here, are looking at only the personal car slice of the picture.

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In a post-oil future I expect that heavy trucks and many medium duty trucks will be hydrogen fueled. I also expect hydrogen to be an important energy storage medium for renewable energy generation. And like most on this forum I don't expect hydrogen fueled personal cars to be prevalent because they will not compete favorably with battery vehicles.

*If* my guesses are right, then the question is how to get there. I don't think a good path is to spend $200M to install a wholly inadequate number of fueling stations for private cars, failing to jump start a fuel cell private car market that is doomed to fail anyway. One better path would be to spend that $200M to install 4,000 more BEV quick charge stations which would probably be adequate to propel the BEV market into the mainstream. Another better path would be to spend that $200M to install hydrogen fueling stations at a few selected locations at trucking company depots, truck stops, and truck scale stations, subsidize some R&D towards building fuel cell heavy trucks, and buying a few prototype trucks to test. Another better path would be to build a hydrogen energy storage facility at a renewable energy plant. Best location would probably be West Texas wind farms but this being California money, maybe a desert solar plant...

walterbays said:

Musk's "energy density" reference seemed doubtful, and I wonder what he really meant by that. The chart you posted looks more like what I'd expect.

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Musk's energy density regarding storage would be referring to volumetric energy density, not weight energy density. And be automotive focused. Take a Tesla Model S or an Honda Clarity, ignore the cost and space taken up by the fuel stack and the second HV battery for fast acceleration/regenrative braking.
The space taken up li ion cells per mile is similar to a 700bar H2 system and significantly better than a 350 bar H2 system. In all liklihood the cost is probably similar as well, although if current CE hydrogen is any predictor, Li ion is probably signifantly cheaper as well.

or to put it another way, Take a tesla model S, replace the 18650 cells with custom made 350bar or 700 bar H2 canistors (but laid flat) and place a fuel cell stack and a HV battery in the frunk, and the range will be similar for the 700bar system but the 350 bar system will be significanlty less range.

More likely, some the HV battery would be kept and the range of the 700 bar H2 tesla would be less than its plain Jane 18650 equivalent. 700 bar H2 would still be classified as a future automotive technology, Tesla's li-ion cells are in mass production and use today. I don't think anyone is currently wishing to go higher than 700bar H2, for cost, and safety, and infrastucture reasons, (actually i would say for H2, even 700bar is somewhat begrudingly targetted for use, 350bar would've been preferred (CNG being safer and simpler, 700bar is good)

ydnas7 said:

walterbays said:

Musk's "energy density" reference seemed doubtful, and I wonder what he really meant by that. The chart you posted looks more like what I'd expect.

Click to expand...

Musk's energy density regarding storage would be referring to volumetric energy density, not weight energy density. And be automotive focused. Take a Tesla Model S or an Honda Clarity, ignore the cost and space taken up by the fuel stack and the second HV battery for fast acceleration/regenrative braking.

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I'd be interested in reading if you'd care to provide a source for your fuel cell/battery comparisons, especially since the Hyundai Tucson fuel cell SUV we've mentioned has a 700 bar system pressure and an estimated max range of about 471 miles. Thanks.
http://www.hydrogen.energy.gov/pdfs/htac_may2012_hyundai.pdf

Although Hyundai has been developing its fuel cell vehicles for more than 15 years, it is only with the start of a viable hydrogen refueling network in place that it is considering putting a fuel cell car into series production, the company said.

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http://www.greencarcongress.com/2013/07/ix35-20130721.html

This, I think, is a key point to remember for our BEV-centric comparisons:

“Designed for Transport for London, the (fuel cell) system saves fuel, allowing these vehicles to operate for up to nineteen hours without refueling.”

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http://www.ballard.com/fuel-cell-applications/bus.aspx

We've had fuel cell buses on the road since about 2007 and they've driven more than 3 million miles. There are plenty of other well-proven fuel cell vehicles available that are not in competition with BEVs, current or near future.

Instead of a turbine EV extender trailer, why not a FCEL range extender? Even if it reformed CNG, it would emit less CO2 per kWh than burning the same CNG...

AndyH said:

ydnas7 said:

walterbays said:

Musk's "energy density" reference seemed doubtful, and I wonder what he really meant by that. The chart you posted looks more like what I'd expect.

Click to expand...

Musk's energy density regarding storage would be referring to volumetric energy density, not weight energy density. And be automotive focused. Take a Tesla Model S or an Honda Clarity, ignore the cost and space taken up by the fuel stack and the second HV battery for fast acceleration/regenrative braking.

Click to expand...

I'd be interested in reading if you'd care to provide a source for your fuel cell/battery comparisons, especially since the Hyundai Tucson fuel cell SUV we've mentioned has a 700 bar system pressure and an estimated max range of about 471 miles. Thanks.
http://www.hydrogen.energy.gov/pdfs/htac_may2012_hyundai.pdf

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And then there's this, from the Toyota FCHV wiki:

"In 2007 a FCHV was driven 560 km (350 mi) between Osaka and Tokyo on a single tank of hydrogen, proving that a hydrogen vehicle could compete with conventional vehicles for range. In August 2009, Toyota USA announced an estimated FCHV-adv range of 690 km (430 mi) from a 6 kg (13 lb) tank of hydrogen, based on a 331.5-mile (533.5 km) test trip in "real-world" conditions between Torrance and San Diego, California.[3]"

http://en.wikipedia.org/wiki/Toyota_FCHV" onclick="window.open(this.href);return false;

One of these Highlander-based 10,000 PSI/700 bar FCHV-ADVs lives at a house in my neighborhood, usually parked alongside a LEAF and a couple of small CUVs. It apparently weighs 4,145 lb. (1,880 kg) using the previous generation fuel cell (the current cell apparently has 3 x [Edit: 2 x] the power density), which is about 500 lb. lighter than a Tesla S-85. Given the relatively barn-door CdA of the Highlander compared to the S, it seems pretty clear that even at typical U.S. freeway cruising speeds a sedan version will have a range well beyond 300 miles, perhaps even 400.

its great that prototypes are doing well but what have they done as far as leakage? compressed Hydrogen leaks at the minimal rate of roughly 2% per day. that means a two week trip will find a third of your tank leaked away. does not bode well for parking it at the airport unless they have a station on premises.

and how long will these tanks last? super high pressures means fatigue and betting we would rather buy new batteries than a new hydrogen tank.

DaveinOlyWA said:

its great that prototypes are doing well but what have they done as far as leakage? compressed Hydrogen leaks at the minimal rate of roughly 2% per day. that means a two week trip will find a third of your tank leaked away. does not bode well for parking it at the airport unless they have a station on premises.

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That sounds a bit like the Tesla Model S, though assumedly the hydrogen would leak faster at high temperatures while the Model S leaks faster at low temperatures.

RegGuheert said:

DaveinOlyWA said:

its great that prototypes are doing well but what have they done as far as leakage? compressed Hydrogen leaks at the minimal rate of roughly 2% per day. that means a two week trip will find a third of your tank leaked away. does not bode well for parking it at the airport unless they have a station on premises.

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That sounds a bit like the Tesla Model S, though assumedly the hydrogen would leak faster at high temperatures while the Model S leaks faster at low temperatures.

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well, i can only reference data from 2006?? (or earlier maybe) but there is a minimal 1.7% leakage daily. that is only the beginning of the issues

Hydrogen is the smallest element and, as such, it can leak from any container, no matter how well sealed it is. Hydrogen in storage will evaporate at a rate of at least 1.7% per day. We will not be able to store hydrogen vehicles in buildings. Nor can we allow them to sit in the sun. And as hydrogen passes through metal, it causes a chemical reaction that makes the metal brittle. Leaking hydrogen could also have an adverse effect on both global warming and the ozone layer.
Free hydrogen is extremely reactive. It is ten times more flammable than gasoline, and twenty times more explosive. And the flame of a hydrogen fire is invisible. This makes it very dangerous to work with, particularly in fueling stations and transportation vehicles. Traffic accidents would have a tendency to be catastrophic. And there is the possibility that aging vehicles could explode even without a collision.

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DaveinOlyWA said:

its great that prototypes are doing well but what have they done as far as leakage? compressed Hydrogen leaks at the minimal rate of roughly 2% per day. that means a two week trip will find a third of your tank leaked away. does not bode well for parking it at the airport unless they have a station on premises.

and how long will these tanks last? super high pressures means fatigue and betting we would rather buy new batteries than a new hydrogen tank.

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The high leak rate appears to apply to cryogenic storage not high-pressure storage, though I'm still looking for actual tested permeation rates for modern carbon fiber tanks with PTFE liners. Anyone?


http://www.rmi.org/Knowledge-Center/Library/E03-05_TwentyHydrogenMyths

http://withouthotair.blogspot.com/2013/04/ive-been-unfair-on-hydrogen.html

http://publications.jrc.ec.europa.eu/repository/bitstream/111111111/6013/1/EUR 20995 EN.pdf

The most recent studies I've been able to find with a cursory search are here:

http://web.ornl.gov/sci/eere/research_fuelcell_storage.shtml" onclick="window.open(this.href);return false;

Haven't read them yet, but it discusses CFRP as well as metal hydride and nanotube storage tanks.

BTW, finally got around to reading the California Fuel Cell Partnership's "Roadmap: Bringing Hydrogen Fuel Cell Electric Vehicles to the Golden State", which was published in June 2012,

http://cafcp.org/sites/files/A%20California%20Road%20Map%20June%202012%20%28CaFCP%20technical%20version%29_1.pdf" onclick="window.open(this.href);return false;

It doesn't raise any points which haven't already been raised here, but does go into more detail. I was particularly interested to see how well my guesstimates as to needed station deployment matched up with theirs. With a few exceptions for obvious destinations and connectors, I was only able to predict the need for stations in fairly large areas, while the automakers have far better (and proprietary) demographic info on where they expect the early adopters to be, and can be far more precise (I imagine down to specific zip codes if not neighborhoods). Worth a read in any case, as it's only 28 easy pages.

Edit: Googling "CFRP hydrogen tank leakage rates" brought up the above source, and also the following link to a book titled "Hydrogen Storage Technologies: New Materials, Transport and Infrastructure".

http://books.google.com/books?id=VmA1n5GS_L4C&pg=SA1-PA9&lpg=SA1-PA9&dq=cfrp+hydrogen+tank+leakage+rates&source=bl&ots=fAGnUJXDgG&sig=lXXr0Do4-_P3HwLUUaOG1ydzFZU&hl=en&sa=X&ei=DTlwUoPhB4iEiwLT2oGYBQ&ved=0CDcQ6AEwAg#v=onepage&q=cfrp%20hydrogen%20tank%20leakage%20rates&f=false" onclick="window.open(this.href);return false;

Clicking on the link will take you to a short section on CFRP tank materials, liners and leakage.

AndyH said:

I'd be interested in reading if you'd care to provide a source for your fuel cell/battery comparisons, especially since the Hyundai Tucson fuel cell SUV we've mentioned has a 700 bar system pressure and an estimated max range of about 471 miles. Thanks.
http://www.hydrogen.energy.gov/pdfs/htac_may2012_hyundai.pdf

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a sample DOE report http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/compressedtank_storage.pdf" onclick="window.open(this.href);return false; on projected Type IV Compressed Hydrogen Storage tank (ie polymer inner liner)
table 3 page 6
350bar tank is 250 L inside volume, 316 L outside volume ie a 26% increase
700bar tank is 145 L inside volume, 224 L outside volume ie a 54% increase over the inside volume

a real III compressed Hydrogen Storage tank (ie Aluminium inner liner) 350bar
http://cldsy.en.alibaba.com/product/628136795-212943568/hydrogen_gas_cylinder_for_vehicles.html" onclick="window.open(this.href);return false;
CHG3-400-74-35A 74 litres inside volume, modelled as a cylinder is 111 litres outside volume ie 50% increase

18650 li ion cell 676 wh/l http://industrial.panasonic.com/www-data/pdf2/ACI4000/ACI4000CE54.pdf" onclick="window.open(this.href);return false;
so Tesla's 85kWh pack contains 85000/676 = 126 litres of cells (outside volume)

honda clarity http://automobiles.honda.com/fcx-clarity/how-fcx-works.aspx" onclick="window.open(this.href);return false;
its tank capacity is 171 L (inside volume) http://www.hondaclarity.org/" onclick="window.open(this.href);return false;

Honda's hydrogen tank is signifiantly greater volume than Tesla's 18650 cells but for less range.
even if extrapolate to 700 bar, then roughly
Honda's 171litre/2 = 85litres inside volume + 45 litres outside extra volume = 130litres total volume

which is close to Tesla 126 litres of cells, except the Tesla goes faster & further and carries 5+2 instead of 4 (Honda)

or to put it as earlier
using a series of optimum sized, 700bar H2 tanks in a Tesla would result in a reduction of range.

looks like this discussion needs to examine why carbon fiber is so expensive. the referenced book mentions several better solutions for hydrogen storage but allude to the fact that leakage still exists and fails to mention what that rate is. I am guessing if you buy the book you will find out

DaveinOlyWA said:

and how long will these tanks last? super high pressures means fatigue and betting we would rather buy new batteries than a new hydrogen tank.

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A paper by Chuan-xiang Zheng et al, http://link.springer.com/article/10.1631/jzus.A1200297 , seems to say that high temperature produced by fast filling shortens tank life.

Jun-ichi Tomioka et al* test Type 3 (aluminum lined) and Type 4 (polyamide lined) tanks. At room temperature Type 3 last 23,000 cycles (which even with daily filling would be 63 years) and high temperature actually improves their fatigue resistance. Type 4 last more than 45,000 cycles at room temperature and 34,000 cycles at high temperature.

Of course I'd want plenty of safety margin since with a battery failure means my range decreases, while with a hydrogen tank failure means a leak of highly combustible gas.

I'm not really so interested in the technical details, but will be content that all the problems are solved when I see a car maker move beyond prototypes, move beyond compliance cars, and actually begin mass market sales of a FCEV. Much as I'd love to be able to buy or rent a little fuel cell to drop in my BEV for range extension on long trips, I think the problems of storage and distribution will be much easier to solve for heavy trucks and delivery trucks. They can carry extra weight and volume of stronger longer lasting hydrogen tanks, or reformer units or whatever it takes. And refueling stations can be conveniently located at depots and truck stops.

*I get SQL errors from the forum however I try to include the paper URL so I'll try this instead: http colon slash slash conference.ing.unipi.it/ichs/images/stories/papers/179.pdf

walterbays said:

DaveinOlyWA said:

and how long will these tanks last? super high pressures means fatigue and betting we would rather buy new batteries than a new hydrogen tank.

Click to expand...

A paper by Chuan-xiang Zheng et al, http://link.springer.com/article/10.1631/jzus.A1200297 , seems to say that high temperature produced by fast filling shortens tank life.

Jun-ichi Tomioka et al* test Type 3 (aluminum lined) and Type 4 (polyamide lined) tanks. At room temperature Type 3 last 23,000 cycles (which even with daily filling would be 63 years) and high temperature actually improves their fatigue resistance. Type 4 last more than 45,000 cycles at room temperature and 34,000 cycles at high temperature.

Of course I'd want plenty of safety margin since with a battery failure means my range decreases, while with a hydrogen tank failure means a leak of highly combustible gas.

I'm not really so interested in the technical details, but will be content that all the problems are solved when I see a car maker move beyond prototypes, move beyond compliance cars, and actually begin mass market sales of a FCEV. Much as I'd love to be able to buy or rent a little fuel cell to drop in my BEV for range extension on long trips, I think the problems of storage and distribution will be much easier to solve for heavy trucks and delivery trucks. They can carry extra weight and volume of stronger longer lasting hydrogen tanks, or reformer units or whatever it takes. And refueling stations can be conveniently located at depots and truck stops.

*I get SQL errors from the forum however I try to include the paper URL so I'll try this instead: http colon slash slash conference.ing.unipi.it/ichs/images/stories/papers/179.pdf

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Hmm...

http://conference.ing.unipi.it/ichs/images/stories/papers/179.pdf" onclick="window.open(this.href);return false;

walterbays said:

Jun-ichi Tomioka et al* test Type 3 (aluminum lined) and Type 4 (polyamide lined) tanks. At room temperature Type 3 last 23,000 cycles (which even with daily filling would be 63 years) and high temperature actually improves their fatigue resistance. Type 4 last more than 45,000 cycles at room temperature and 34,000 cycles at high temperature.

Click to expand...

And what is the cycle life for consumer automotive use where zero failure is acceptable?
I believe the article did say fatigue damage was not linear and rather accelerated at the end of life.
May not matter if these are lease only vehicles like the Honda.

smkettner said:

walterbays said:

Jun-ichi Tomioka et al* test Type 3 (aluminum lined) and Type 4 (polyamide lined) tanks. At room temperature Type 3 last 23,000 cycles (which even with daily filling would be 63 years) and high temperature actually improves their fatigue resistance. Type 4 last more than 45,000 cycles at room temperature and 34,000 cycles at high temperature.

Click to expand...

And what is the cycle life for consumer automotive use where zero failure is acceptable?
I believe the article did say fatigue damage was not linear and rather accelerated at the end of life.
May not matter if these are lease only vehicles like the Honda.

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The papers I've found for H2 tanks echo other auto engineering pieces I've read - they both appear to use about a 240-250% safety margin. I'm not sure if this applies to cycling/lifespan calcs, but does apparently apply to design parameters for pressure tanks - a 700 bar tank should have a design limit of between 1680 and 1750 bar. :shock:

http://www.pnl.gov/fuelcells/docs/summits/summit8/presentations/day2/abele_915am.pdf
http://publications.jrc.ec.europa.eu/repository/bitstream/111111111/6013/1/EUR 20995 EN.pdf
http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/compressedtank_storage.pdf
http://h2bestpractices.org/docs/Doc100_03H2CylindersandTransportVessels.pdf

http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/cng_h2_workshop_5_hennessey.pdf
http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/cng_h2_workshop_8_wong.pdf

ydnas7 said:

AndyH said:

I'd be interested in reading if you'd care to provide a source for your fuel cell/battery comparisons, especially since the Hyundai Tucson fuel cell SUV we've mentioned has a 700 bar system pressure and an estimated max range of about 471 miles. Thanks.
http://www.hydrogen.energy.gov/pdfs/htac_may2012_hyundai.pdf

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a sample DOE report <snip>

or to put it as earlier
using a series of optimum sized, 700bar H2 tanks in a Tesla would result in a reduction of range.

Click to expand...

Thanks. While it's interesting to do a volume comparison, I don't think it's of any real-world value, since we're not talking about removing the battery from a Model S and trying to replace it with a fuel cell system.


Source: http://www.pnl.gov/fuelcells/docs/summits/summit8/presentations/day2/abele_915am.pdf

The goal of the H2 roadway is to replace fossil fuel use. There are vehicles on the road today with 700 bar systems that do not encroach on passenger volume, provide a 400+ mile range, and return more than twice the energy efficiency of their gasoline-powered sibling. That seems like a very good thing to me.

Edit... This seems relevant. Earlier when we talked about density, the 800 Wh/kg number was shown for the airborne fuel cell system. That wasn't for the hydrogen storage tank - that was for the entire system - tank, fuel, fuel cell, and peripherals.

A couple of ramblings for what they're worth...

I'm finding that the H2 research I did about 15 years ago is horribly out of date. Some companies that made membranes or H2 sensors no longer exist, others have been 'born'. Tech has changed, goals appear to have changed, and so have politics. Trying to get back up to speed feels a lot like starting over.

What I'm using for the policy background - to try to answer the question "why hydrogen" and/or "why hydrogen now", is a combination of Rifkin's "Third Industrial Revolution" and RMI's "Reinventing Fire". Both are being used in the 'real world' to steer local, state, and national governments as well as power companies to transition away from fossil fuels by 2050.

I have to keep reminding myself that it's twice as efficient to use natural gas in a fuel cell than in a combustion engine. My gut feeling using horribly simplified numbers is that even if all our transportation comes from fuel cell vehicles (no BEVs), that energy use and greenhouse gas emissions would both drop significantly compared with burning CNG, gasoline, and diesel as we do today. Fuel cells are about 40% efficient in vehicle use when the hot water is not used, and about 80% efficient when used in stationary combined heat and power plants for homes and businesses. While today most of our H2 comes from fossil fuels, we have the tech to completely replace those with electrolysis, biomethane, and other renewable sources using current tech. According to Janine Benyus and her biomimicry work, researchers reverse-engineering photosynthesis to make better solar collectors are also finding biological ways to produce H2 the way nature does - with sunlight, at room temperature, in water, with no waste.

Oil companies are not my favorite businesses on the planet. Not because they have more money than many countries - they exist to make a profit - but because of the damage done by extracting raw materials and dumping wastes. Is it ok for Exxon to continue to exist in a 2050 future if they still process petrochemicals, but if a majority of their cashflow comes from providing H2 with electrolysis, or by owning wind farms, or performing other non-extractive/non-polluting functions? I ask this from a point of view inside a post 2050 world where most H2 is supplied locally as part of the distributed and renewable 'energy internet.'

What scares me about our energy transition is politics. In Germany and the rest of the EU, the governments appear to be able to steer the power industry. In this country, especially if left to the whims of low-information voters, energy companies can steer the government. I hope this is something we can fix.

edit... PS - According to the EIA, California produces more than 1/3 of the country's H2...
http://www.eia.gov/dnav/pet/PET_PNP_CAPPROD_A_(NA)_8PH_MMCFD_A.htm

Thanks everyone - my head hurts now. It's ok - that's a good thing. :lol:

walterbays said:

*I get SQL errors from the forum however I try to include the paper URL so I'll try this instead: http colon slash slash conference.ing.unipi.it/ichs/images/stories/papers/179.pdf

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I get a lot of SQL errors from non-printing characters in PDF files as well. More often than not, I have to either paste the text into a software development editor that shows all characters, or retype from scratch.

"It's not you" is my intended takeaway.

Found the following NREL report, which describes the range verification test done for the Toyota FCHV-ADV (the Torrance-LA-SD and return real-world 331.5 mile drive I referenced a few posts back):

http://www.nrel.gov/hydrogen/pdfs/toyota_fchv-adv_range_verification.pdf" onclick="window.open(this.href);return false;

It describes the vehicle as well as the test, the latter in great detail.