Efficiencies of Hydrogen

<div class='quotetop'>QUOTE(Fibb222 @ Dec 13 2006, 09:22 PM) [snapback]361930[/snapback]</div>

Hi Fibb,

But if one compares that the reformed natural gas would have gone to heat a house, at 70 to 90 % efficiency, hydrogen fuel cell vehicles then wastes on a well to human benefit basis about half of the energy in the natural gas. And in the meantime, we have to pay more for heat, or natural gas electricty.

A Prius can be converted to run on natural gas. So, now your hybrid well head to wheels efficiency is more like 35 % (2004 generation Prius). Although, we still get to pay increased natural gas bills.

Hydrogen FCEV using electricty to reform the hydrogen from water is bad too. Because one could put the electricity in an EV and get nearly 1.5 to 2 times the energy benefit.

The best way to use natural gas is for heating. Its more efficient in heating than any other method of using it.

 

<_< I believe this belongs in "Fred's House of Pancakes"

 

Probably true Charles, but it's still a good topic, so i'm gonna post now, and hopefully the mods can move it over later...

Hydrogen has plenty of downsides, and from what i can see not a lot of upsides. From the excerpt you posted (sorry, but i don't have time right now to read 50 pages), it sounds like they aren't taking into account energy expended for transportation or refining or distribution - all of that stuff probably actually brings the overall energy expended verus energy delivered to the wheels into the negative, and unfortunately i don't know which one would be better.

Hydrogen is highly combustible, which makes it dangerous in accidents (I'd say probably even more dangerous than gasoline). This is a huge problem that i don't think is solved in a satisfactory manor yet.

Many of the proposals concerning where to get hydrogen from, such as natural gas, result in an overall decrease of efficiency when compared to what that source could otherwise be used for. Additionally, the infrastructure required to distribute Hydrogen simply isn't there, and will be expensive to rush to market.

BEV's, on the other hand, benefit from many of the pluses of hydrogen: They're more efficient than gas (if you do an outlet to wheels comparison), and it's much cleaner than gas (if the electricity comes from a clean source, which is debatable). Additionally, there's no additional infrastructure needed - any outlet will do! And finally, it's much safer than either gasoline or Hydrogen, because the storage medium isn't combustible (unless you buy from Sony :lol.

Hydrogen does have it's uses, IMO. There's a company based in Pittsburgh that owns a patent developed by Honeywell which is allowing them to develop industrial fuel cells that can create hydrogen from what is otherwise considered industrial waste for certain industries. This allows those companies to supplement their electric needs with electricity created from their own waste products - pure genius!

But when it comes to auto's, i strongly believe in the PHEV/BEV route - There are just too many questions in Hydrogen.

 

The one big question about hydrogen that never seems to be addressed anywhere is where the heck do we get all the platinum that's needed for the fuel cell catalyst?? There was one estimate that I read somewhere that said that based on today's fuel cell technology and the amount of platinum that each cell used, there was not enough platinum on the earth to replace every car in the US (never mind the rest of the world)with a fuel cell equivalent.. Plus, using up all that platinum for vehicles would deprive many other industries of this necessary catalyst, including a great deal of food and drug manufacturing..

The only other route for hydrogen is a hybrid electric and internal combustion engine based on hydrogen, but the issue here is that the energy from burning hydrogen is absolutely miniscule compared to burning the same volume of gasoline..

It seems to me that unless someone develops a Mr. Fusion unit in the next couple of years, hydrogen is at best a pipe dream..

 

I want completely solar, no delivery or refining costs.

 

First, while hydrogen is "highly combustible", all fuels are. People think hydrogen is dangerous, that it will explode. It will only explode when mixed with the proper quantity of oxygen (or chlorine). If you take a balloon inflated with hydrogen and light a match to it you just get a nice gentle flame.
In an accident severe enough to pierce the hydrogen fuel tank survival would be questionable. However, the benefit of hydrogen is the fuel escapes to the sky, so any fire is over the victims, not around them. With liquid fuels such as gasoline and diesel you will be sitting in the pool of burning fuel!
It gets worse! A gasoline fire is more dangerous than a hydrogen fire. There is more energy per volume. A diesel fire is worse yet!

The first use of hydrogen will be as a replacement for gasoline, burning it in an ICE just as natural gas can be burned in an ICE. In this use it is subject to the efficiency of the ICE, something like 25% overall. Mazda has shown several hydrogen powered concept cars in the last few years. The benefit is essentially zero emissions. Unless you consider H2O toxic.
The problem with hydrogen is getting enough in the car to give a reasonable cruising range. The battery technology used in the Prius is being used to help with this - NIMH "metallic foam" sequesters H2 at "low pressure" allowing 2-5 times as much H2 to be stored in a reasonable size tank. When these tanks are burst H2 escapes slowly as well, so they are safer in that respect (no 3000 PSI tank pressure explosion).

The major restraining factor right now is availability. That is being addressed by some govts. (California for one). Once the fuel is widely available vehicles capable of using it can be widely sold.

As far as efficiency, I've now read two opposite views. One says it's wasteful to produce H2, the above quoted one says it isn't. Why do people have to spin facts to their own benefit all the time!? Let it happen, there is plenty of energy money to go around!

 

A major hurdle with any technology is people need to stop thinking in terms of "Not everyone can use it". Of course not, stop thinking totalitarian and think diversity. SOme people using, gas, some using, bio, some using fuel cells, others with full electric etc etc. There are too damned many of us to be usingf one fuel source only. Just like we shouldn't all be eating only 4 kinds of grain.

 

Most hydrogen critics are a bit short sighted. All they are willing to see is Natural Gas Reformation and Electrolysis as production methods for hydrogen.

And they're right in the near term. These are undoubtably the ways hydrogen will initially be produced. But that's where the critics are short-sighted. They refuse to see these as the interium steps that they are, and base all their arguments on the sustainability of those short term solutions.

They are all ready to quote how battery research is progressing further every day, but they refuse to even consider the fact that hydrogen research is ongoing too. The natural world has thousands of different mechanisms for splitting water molecules and researchers are learning how to tame these processes. Its not hard to find articles about research in the use of bacteria, algae, protiens, and even molcules commonly found in blood to produce hydrogen from water.

Or how about we talk about so more here and now production techniques. My favorite one, which a German company and been doing, is to mount windmills on tanker ships that sail out into the open ocean to harvest the plentiful winds and produce hydrogen from sea water. They can move where the winds are strongest and then sail back into port when their tanks are full. Or how about places like Iceland, that have plentiful geothermal energy to produce a lot of electricity, but can't transmit that electricity to places like North America. However, they can use the electricity to produce hydrogen and ship that around the world.

So, while the critics may have a valid argument that an EV car that directly utilizes electricity is more efficient than a car that uses hydrogen that was produced by the same electricity, they won't be able to convince me that a car in North America that was charged by a coal fired power plant is more energy efficient that a hydrogen car whose hydrogen was produce by wind power in the open ocean, geothermal power from iceland, or solar power via algae.

Get cars off of gasoline and onto hydrogen, and when the demand for hydrogen ramps up, companies all over the world will be vying to find the cheapest way to produce it.

As far as the platinum issue goes... Platinum is not the only metal they can use in a fuel cell; its just the best material they've found so far. Plenty of research is going on to find a replacement. For all you battery people, think back about 15 years ago when Ni-Cads or Lead Acid batteries were the only technology out there. That's where we are with fuel cells. We have materials that work fairly well now, but there's plenty of potential for better materials to be developed.

 

Hi Fibb and Marlin,

Its not really the critics that are short-sighted, its the proponents. They cannot wait for the technology to catch up, to the vision.

As to vehicle application, I think reformation of coal-gas would be better to get us off petroleum, and also as a a way to clean up electric generation for EV's. This process can take out some of the coal impurities. And the coal-gas is the feedstock for Fisher-Tropf (spelling?) synthetic diesel or gas. The diesel can be used in the winter, and bio-diesel in the summer for rural operating vehicles. It really should be mandated for electric generation plant fuel. The pipeline delivery might save enough money to pay for the processing. And vehicle fuel would be a byproduct.

Add in bio-butanol ( http://www.butanol.com/ and http://www.bp.com/liveassets/bp_internet/g...sheet_jun06.pdf ) and you get a long term storable solar, cabon cycle fuel, with nearly the same energy density as gasoline. Run the farm equipment on Bio-diesel, and use geo-thermal to heat the fermenters and its pretty green (until the Sierra Club finds the geo-thermal pipe running out of Yellowstone, and down the side of Mt St. Hellens, or through the lava-fields of Hawaii). No engine/pipeline/fuel tank mods needed. And no other fuel oxygenators either.

If you want something for the next generation of metropolitan cars - its bio-butanol/Fisher-Troph gas turbo-charged 1.1 liter plug-in Prius. Get 50 % of the commuters driving something like this, or the mini-van variant, and petroleum will take centruries to run out, as we will mostly be using it to make the car bodies.

Do not get me wrong, I do not know the real answer. I have supported FC vehicles on Prius Chat, as the weight of the FC can be allot less than the batteries. And with appropriate technolgy, its might become cheaper. This probably will take nano-particle engineering to make an economic PEM catalytic surface, and extreme carcinogen controls. Do chemist really know what makes Platinum tic? It has not happened yet.

The EV people think that is wrong, I think its a matter of some decades. Can the FC run backward? If not you basically need a hybrid car with twice the motor size - yea you still need the Prius battery - to recover decell/drop energy. That is, a Prius with two motors and a two generators, twice the battery, and the FC, and without a heat engine.

What is driving the Hydrogen FC is the tones of money being dumped on it from politicians. Why is GM is not funding it themselves with profits from sales of EV1's ? Not sure. Kinda wierd. Kinda like maybe its a con job. A scenario might go like this - "gotta EV1, Love it!, Want more range for the weekend trip without the 3 tons of SUV to hall those big batteries? Well step on up to the EV2 with FC trailer - the trailer has a big luggage bay on top! and its own regenerating brakes".

Probably the only place for electrolysis hydrogen right now would be to store enviormental heat energy in an EV car, to heat up the battery so it can run at 0 degree F outdoor temps. Just plug the car in at night, and you have enough hydrogen to reheat the car after work. Water and Hydrogen in a closed loop. Could do that with natural gas and catalytic combusters too - like those propane radiant heaters contractors use, though.

 

<div class='quotetop'>QUOTE(c4 @ Dec 14 2006, 11:20 AM) [snapback]362131[/snapback]</div>

Global production of platinum is 190 tonnes per year.

The very best fuel cells (ie using the least platinum) use 100 grammes per vehicle, and there is no sign of a change in this soon.

If the entire Earth's global supply of platinum was used to make fuel cells for vehicles, that would add up to only 1.9 million cars per year, or 3% of current worldwide production.

However I suspect that the other platinum-using industries in the world may complain about losing 100% of global platinum production to supply engines for a small number of highly energy inefficient cars.

 

Clett- Exactly! Thanks for the confirmation- we simply don't have enough platinum at today's usage levels to make large scale use of fuel cells practical.. Yes, fuel cells have come a long way in reducing the amount of catalyst material needed, but it is still not zero.. In terms of other alternative metals, most are still platinum-group metals (rhodium, iridium, etc), which are still more rare than platinum; there are some non-platinum catalysts in research stages, but they are all still highly inefficient and basically kill any economic benefits of hydrogen.. Perhaps in 15-20 years fuel cell technology will be ready for prime time, but it's still very premature IMO..

I suppose, to play devil's advocate, one should ask the other obvious question- is there really any reason why we *need* 1.9 million new cars every single year?? Cars, even the excuses that are called "cars" coming from GM, do last for more than just a few years nowadys, so short of blatant consumerism, we really don't need to keep "upgrading" vehicles every other year.. Assuming that some revolutionary technology that will save the planet doesn't come along tomorrow, I fully intend on keeping my Prius (2001 Classic Prius) for as long as it will drive and parts are available for it..

 

I think car companies are enamored with hydrogen and ethanol just because they can keep their oil buddies happy. Both indirectly use oil, just adds more steps to get the energy to us. They both also need to be pumped by an oil company-controlled small (inefficient) station.

I think we should put all our efforts into producing electricity efficiently from whatever means, at a large (efficient) station and then distribute the energy to our cars. That way as electricity production becomes more efficient everyone benefits and contributes.

 

It's also rarely pointed out that platinum also currently costs $40 per gramme, so a 100 gramme FCV catalyst would cost $4,000 in platinum costs alone. If you started building lots of fuel cell vehicles, the pressure on platinum supply would only push this cost up, not down.

 

Production of hydrogen requires energy. Using fossil fuel (natural gas) to produce hydrogen begs the question. We want to get away from fossil fuels and the pollution they produce. The figures for conversion efficiency of gas to hydrogen to wheels are theoretical. The figures for the Prius are real. Even the most enthusiastic hydrogen promoters admit that hydrogen powered vehicles are 10 years away. In those ten years, how much will the efficiency of the Prius be improved? Plug in cars are no different. They use fossil fuel burned at the power plant. The overall efficiency of mine to wheels will probably be very low for plug-in cars. And just wait until you run the heater at -20 deg.

There is an answer: produce the hydrogen with nuclear power. Charge the batteries with nuclear power. No fossil fuels, no air pollution.

 

<div class='quotetop'>QUOTE(wauwis @ Dec 25 2006, 09:50 PM) [snapback]366626[/snapback]</div>

That is the most viable solution as a lot of people see it right now.

 

Generation, storage , transport and distribution of hydrogen is going to require a huge capital infrastructure that currently doesn't exist.

Current hybrids use gasoline that is produced and distributed very efficiently and future plug-in hybrids and all-electric vehicles can use the existing electricity grid. These are here right now!

It seems to make more sense to me to use electricity directly than to use it to generate hydrogen, particularly given that even currently available batteries are up to the job.

I'm afraid that I have to agree that the argument put forward in "Who Killed the Electric Car" - namely that the hydrogen industry is a ploy by the petroleum interests to cement their market share - looks all too true.

I think that hydrogen power is a mare's nest!

Mike