Hydrogen fuel cell, good or bad idea?

[soletek]

Just spent the morning at a presentation prepared by the state of CA, in Sacramento, regarding the development, so far, of the Hydrogen fuel cell. There were 7 or 8 vehicles on display. They were offering test drives and rides. After seeing the line I declined the ride. However, I listened to the presentation and watched the slide show. I asked a few questions and listened to other's questions. The idea sounds very intriguing, but the response of the group with me was generally disappointment. I posed quite a few of the same questions to different staff at different locations in the event. There were at least three different answers to the same question from three different people. I.e. I asked, "How many miles do you get from a filled tank of hydrogen on a general passenger car platform?" One answer: fifty miles to an equivalent gallon. (The tank, which is massive, holds only 4 gallons equivalent to gasoline, but takes up the area of about a 50 gallon gas cylinder.) 300 miles to the tank was the response. I don't know about your math, but mine doesn't say that adds up. Second answer: 200 miles per tank and the third answer: up to 200 miles per tank. A question posed by a person with me was, "What is the life expectancy of the fuel cell?" One response: 5000 hours use before one of the 16,000 membranes in the four cell stacks fails. Second response: 80,000 miles. Third response: these vehicles were built to a standard of 150,000 miles, or ten years before rebuild, just like cars today. Do the math on these. Are you as perplexed as I am?

One thing we did find out was that they built the fuel cell groups designed for anode, membrane, and cathode to be replaced -- plug and play, I guess. I asked the weight differential with all the lightening (carbon fiber, aluminum and such). These vehicles weigh 300 to 500 lbs more than their equavalent gasoline counterpart.

The wonderful pluses, in my opinion, that come from the design are: 0 in-use emmisions; no additional chemicals--oil, transmission fluid or anything else that can leak out of a vehicle; internal domestic value (all can be done here, no importing); creates jobs in the US; hydrogen can be produced from almost anything, not just water, but even from bio-mass; such as the stocks from rice that are normally burned. Hydrogen can be produced from solar/wind energy and water. Additionally, an interesting fact: Sierra Nevada Pale Ale is a company that uses hydrogen to manufacture all of their beer. They use the process of the beer making to produce the hydrogen that makes the electricity to run the entire place. That's cool.

When questioned on how close we are to using this technology, after quite a bit of dodging the question, the response was a definitive, "I don't know," and a bunch of excuses about the inability to build filling stations at a rate to support more than the around 200 cars that presently exist. The vehicles in CA are leased in LA for around $600 per month for testing. Generally as fleet cars for the government and mass transit.

They were surprised at the turn-out of so many people. It was very surprising that they were surprised.

"What does the hydrogen cost per equivalent gallon of gas?" was asked. The response was: About the same as gasoline without the road tax, and we don't have to pay a road tax at this time.

I'd like to read some of your ideas and opinions about hydrogen fuel cells!

[Ryland]

My information is from about two years ago, so it's a little dated, but at that time fuel cells were expected to last 25,000 miles, and cost around $20,000 to replace, this is because they are fragile, and putting them in a vehicle that is moving around, and hitting bumps in the road is an extremely harsh environment for them, they also need pure, clean air, even air filtered to the point that your car's air is currently filtered is going to cause wear and shorten their life.
But the main thing is, a fuel cell is just a battery, a battery that can be mechanically recharged, but it is still just a battery, and not a vary efficient one at that, last I heard it was about 35% efficient in converting hydrogen back to electricity, but most of the energy is use in compressing they hydrogen, 80% of the energy that is in the hydrogen it's self is use in compressing it to 10,000psi (that big tank, it's a very "fluffy" fuel even after it's highly compressed!), but yes, you can use solar or wind or hydro to produce it, just like you can use that to power your home! and although people are powering their homes that way, it's not the popular way to do it, and when people are handed an expensive technology, they are going to look for short cuts in other areas, and more so if they don't have to look at the coal power plant smoke stacks.

[JoeBob]

Dunno...hydrogen still scares me. Oh, the humanity!

[cfg83]

soletek -

I believe in continued research but I do not see fuel cells as near-term solutions. No [hydrogen delivery] infrastructure, no fuel-cell cars. However, in very old news, Amory Lovins has argued in favor of a Fuel-Cell energy economy :

Amory Lovins Sees The Future and It Is Hydrogen - May 4, 1999
http://www.pcdf.org/meadows/hydrogen.html

Picture this. When you get up in the morning, the electricity you use comes from your basement fuel cell, about the size of an air conditioner. The heat it generates gives you hot water for your shower. The hydrogen it consumes could come from a pipeline, from a neighborhood or rooftop solar array, or from a natural-gas fired "hydrogen appliance" also in your basement.

You hop into your Hypercar and go off to work. Only your tires make noise; only water remains in the air behind you. When you pull into your parking space at work, you snap two connectors onto your car. One reloads your fuel cell from the industrial-size hydrogen-appliance at your workplace. The other is an electric line that takes power all day from your fuel cell and calculates how much you're owed for the electricity.

As Lovins says: "While you sit at your desk, your power-plant-on-wheels is sending 20+ kilowatts of premium-quality electricity back to the grid.... Thus your second-largest, but previously idle, household asset is now repaying a significant fraction of its own lease fee. If a modest fraction of drivers took advantage of this deal ..., most or all existing coal and nuclear power plants could ... be displaced. Ultimately the U.S. Hypercar fleet could have four or more times the generating capacity of the national grid."

Says Lovins: "This approach offers several strategic advantages. It uses idle off-peak capacity in the natural-gas and electricity distribution systems that have already been installed and paid for. It is build-as-you-need and pay-as-you-go, requiring investment only in step with incremental demand. It is one or two orders of magnitude cheaper than building a dedicated, centralized hydrogen production and delivery system from scratch.... And vibrant competition between gas- and electricity-derived hydrogen, ... will exert downward pressure on the prices of hardware and hydrogen."

No, you can't buy a house-sized fuel cell, yet, or a hydrogen generator, or a Hypercar, though prototypes do exist. Yes, right now the technologies are expensive. But factor in the avoided costs of air pollution, global warming, defense of the Middle East, central power plants, and long-distance electric wires and they don't look so bad. Right, this system still doesn't solve the problem of traffic jams and parking places. Lovins has some ideas about that too.

Here's a more recent article (2007 I believe) :

Reinventing the Wheels: The Automotive Efficiency Revolution
http://usinfo.state.gov/journals/ite...jee/lovins.htm

... In the longer run, one can make a robust business case for tripled-efficiency, ultralight-hybrid cars to use compressed hydrogen gas as fuel and turn it into electricity in a fuel cell. A heavy, inefficient car would need an excessively bulky tank and a big, costly fuel cell. But an ultralight, aerodynamic car would need two-thirds less propulsive energy and smaller tanks. And just 3 percent as much cumulative production volume would be needed to make the three-fold smaller fuel cell cost effective?thus it could become cost effective many, many years earlier. Such cars when parked (which is 96 percent of the time) could even become profitable power plants on wheels, selling electricity back to the grid when and where it's most valuable. In a parking structure, there would be a pipe to get hydrogen into the car and wires to get electricity out. At times of peak power demand, you could turn the fuel cell on and the car could run as a power plant, crediting the owner's account. ...

You can read this for the cost of your e-mail account :

Winning the Oil Endgame
http://www.oilendgame.com/

CarloSW2

[JanGeo]

The fuel cell works great in a space ship that uses liquid Hydrogen and liquid Oxygen for fuel for the rocket motors since you just tap into the rocket fuel tanks to run the fuel cells. Other than that you can pretty much forget about using them in a car since the energy to move a big heavy car will require all sorts of power to keep the cells cooled and of course the storage of Hydrogen for fuel is very low energy dense. If the world can't build electric cars today with the much higher battery energy density for a souce of power they for sure are not going to build a car powered by even less energy dense fuel cells. Keep in mind one other thing about an electric car powered by batteries - Air or oxygen does not come into the energy equation at all - you simply charge the battery off the wind (ok there is air there) - water - solar and drive. There are large long lasting and powerful Lithium Cells being made in China already but the Patents that OIL companies own prohibit their large scale use in the USA since China does not adhere to the patent laws.

[soletek]

Thanks, I really appreciate all your input on the subject. In analyzing such an issue, many heads are better than one.

The problem with the lithium-ion battery is that it is not as good as it is hyped to be. They have good long-term low-drain stability but are not capable of the high load demands required by the acceleration of an electric car. That is why all of the hydrogen powered vehicles have an additional nickle-metal-hydride or lead-acid battery array to aid in everyday driving conditions. I was told at the event by their service tech that they don't use lithium-ion batteries in those cars, at all.

The biggest problem with the Prius, for example, is that at purchase the new battery performs at peak levels, but, in short time (two months or so) it drops by about 15% on its recharge capability and planes out there for the majority of its life. That means it runs on the gas engine more than it did in the beginning. This is why when they are purchased they get close to the 60s mpg but drop very soon to high 40s mpg. All of the owners that I have asked what they get in real world all-around dirving conditions say: a low of 46 and a high of 48. This includes a dozen or so owners so far.

The additional batteries required in the hydrogen car add a lot of weight, and the storage cell takes up a lot of space for a small capacity of fuel. If you take their calculation of 5000 hours use time, and you plug that into your house or business which might be powered for 24 hours a-day, it would last 208 days before it started to lose cells and require rebuilding. Who gets to foot that bill?

One thing I noticed, having been to an event about ten years ago, there has not been much progress.

[molecule]

i'm still a believer that enough hydrogen could be produced by fracturing and resonance (stanley meyer method) of water in the car.

[Ryland]

Yes, it's true that some older lithium batteries don't deal well with sudden high loads, but the same is true for fuel cells, fuel cells are often used with a battery buffer, often a lithium battery is used, the Lithium batteries I have for me E-bike (A123 batteries) have cells that can be recharged to 80% in around 5 minutes without damage (according to specs) and after 2,000 cycles are supposed to still have lost only 20% of their over all capacity, to me that would mean that you could almost turn gas stations in to charging stations, stop for 5 minutes, charge your car and continue on, or have parking spots with chargers and coin slots or a card swipe.
I'm suprized that the idea of fuel cells is still around, lithium batteries are cheaper, should last longer, and although they require exotic metals, the ones that they require are more common and cheaper.

A fuel cell car is just an electric car with a fuel cell battery, it's not magically turning the hydrogen in to motion.

[Sludgy]

I get tired of hearing about "unobtanium" technologies, when the solution for energy efficiency is already well known. 80 MPG cars are already here, like the VW Lupo. We just can't buy them here because of Stupid Federal Regulations.

The fuel economy solution is simple: light weight, reasonably aerodynamic vehicles with small engines that operate near full load under nearly all driving conditions.

[JanGeo]

Lithium cells with high output are available and they also have cycle life in the thousands like 2000-3000 before they drop to 80% which is still usable and they can last longer when not discharged as deeply i.e. 70% DOD. Output current is usually more than 2C but you have to get big enough cells to provide the higher currents needed for car size vehicles. There are home car builders out there doing it already.

As far as the Prius is concerned I got a little over 60mpg highway and rush hour traffic combined with a 2007 model with 19k on the clock so the battery myth is a user problem - they get into the lead foot mode of driving after a while and don't brake slow enough to get max regen energy back into the battery as does the present owner of the Prius I drove. I sorry but you can't expect to get all that braking energy from 30mph with a 50 foot stopping distance - it takes braking slowly to maximize the regen. As a result users don't get the gas savings they could if driven properly.

Now as far as the 5000 hours power life I figure that I go through a tank of gas in 20 hours (ScanGauge numbers) or less sometimes with a little over 400 miles traveled. That translates to 250 tanks of fuel or 100,000 miles with an average speed in the 20mph range so higher speeds and the fuel cell will give a pretty good service life.

Not too many people are going to be powering their house with their vehicle electrics to offset grid peak demand unless the neighborhood is all charging their cars during peak hours and causing brown outs. It just cycles the battery/fuel cells too much. Power can be generated from neighborhood generators like microturbine plants much more cheeply in most cases for less than grid power.

[StorminMatt]

Originally Posted by Ryland

I'm suprized that the idea of fuel cells is still around, lithium batteries are cheaper, should last longer, and although they require exotic metals, the ones that they require are more common and cheaper.

A fuel cell car is just an electric car with a fuel cell battery, it's not magically turning the hydrogen in to motion.

The reason why fuel cells are still around is that they have one distinct advantage over ANY type of rechargeable battery: you don't have to wait HOURS for the battery to recharge. You just refuel and go, just like a conventional car. Recharging time has ALWAYS been the BIG downfall of battery electric vehicles. I myself could live perfectly FINE with a vehicle that can only go 150-200 miles before recharging/refueling (I don't know why people care SO much about not being able to go 400+ miles without refueling). But if it is going to require six hours of charging, this is a deal killer for ANYTHING but a commuter that can be charged overnight and/or at work. And unless that electric 'second car' is going to be cheap, it is just not going to be worth buying for MOST people.

As for the fuel cells themselves, their efficiency (at around 50-60%) leaves something to be desired. After all, this level of efficiency can be achieved by gas turbines. And gas turbines last a LONG time (compared to fuel cells and, for that matter, reciprocating engines). They can also burn a wide variety of fuels (including biodiesel and straight vegetable oil). But keep in mind a couple of things. First of all, this is really not much less than NiMH batteries. And NOBODY talks about how inefficient NiMH batteries are. And secondly, fuel cell technology is VERY much in its infancy (even compared to more advanced gas turbines). Efficiency has increased by quite a bit over even a few years ago. And I would suspect that it will imcrease further in the future.

Hydrogen production, on the other hand, is a BIGGER issue. Simply put, we really do not have a good way to make it. One way is from fossil fuels, either directly or by electrolysis of water using electricity made by burning fossil fuels. Neither of these methods are very efficient. And when combined with all the other losses in the entire hydrogen cycle, you are probably better off just burning the fossil fuels in a regular car like we do today. Another thing that few people consider is that if EVERYONE starts using grid power to make hydrogen, the grid will just not be able to handle it without large upgrades and additional power plants. So along with the greater inefficiency will come large infrastructure costs. You are beginning to see that this is not such a hot idea from the supply side.

So what about using wind and/or solar power to make hydrogen? In theory, it is an EXCELLENT idea. BUT, how much power is currently generated by wind and solar? I can't quote exact figures. But I believe it is well under 10%. In other words, we couldn't hope to make a dent in the current demand for energy to power vehicles with hydrogen made from wind and/or solar power (or other renewables, for that matter). And nothing short of a breakthrough in terms of drastically lowered cost of photovoltaics is going to change that. Now if we ever see photovoltaics at $.50 per watt, hydrogen will look ALOT more attractive. But I personally see higher fuel cell efficiency happening before THAT happens.

[Sludgy]

Originally Posted by StorminMatt

As for the fuel cells themselves, their efficiency (at around 50-60%) leaves something to be desired. After all, this level of efficiency can be achieved by gas turbines.

I liked the thrust of your post, but I did want to amend the above statement.

Only extrememely large (Utility-sized) combined cycle gas turbine plants approach 60% efficiency. GE is the only company that claims to reach 60%, so far as I have seen.

Automotive size gas turbines only achieve ~30% efficiency, and this is when they are equipped with exhaust heat recuperators.

Simple Brayton cycle turbines under 500 HP usually have less than 20% efficiency.

[JanGeo]

Actually there is a microturbine being used to generate electricity at the neighborhood level with the 300 degree exhaust heat used for building heating that approaches 90% efficency. The company is supposed to be in production of these generators right now.

http://www.microturbine.com/prodsol/products/index.asp

[StorminMatt]

Originally Posted by Sludgy

I liked the thrust of your post, but I did want to amend the above statement.

Only extrememely large (Utility-sized) combined cycle gas turbine plants approach 60% efficiency. GE is the only company that claims to reach 60%, so far as I have seen.

Automotive size gas turbines only achieve ~30% efficiency, and this is when they are equipped with exhaust heat recuperators.

Simple Brayton cycle turbines under 500 HP usually have less than 20% efficiency.

Check out this microturbine:

http://www.wilsonturbopower.com/micro_overview.html

The efficiency of the genset is 50%, so the efficiency of the turbine itself is pobably closer to 55%. And this is WITHOUT taking congeneration into account. True, it is still somewhat in the developmental stage. But it looks promising.

What's interesting to note about this particular turbine is that it is largely an axial flow design. Only one stage of the four stage compressor is centrifugal. And the turbine is a three stage axial flow turbine. This contrasts with most small gas turbines (ie those that have been used experimentally for automotive use), which are typically single stage centrifugal designs on both the compressor and turbine - not an efficient design. Indeed, the fact that small gas turbines typically use this inefficient design is probably THE reason for the low efficiency typically seen in turbines producing under 500HP. For this reason, I am hopeful about this particular turbine. But whether it can be produced at a reasonable cost is another matter. After all, cost is probably the BIG reason why horribly inefficient designs are used for small gas turbines.

[Ryland]

Originally Posted by StorminMatt

The reason why fuel cells are still around is that they have one distinct advantage over ANY type of rechargeable battery: you don't have to wait HOURS for the battery to recharge. You just refuel and go, just like a conventional car. Recharging time has ALWAYS been the BIG downfall of battery electric vehicles. I myself could live perfectly FINE with a vehicle that can only go 150-200 miles before recharging/refueling (I don't know why people care SO much about not being able to go 400+ miles without refueling). But if it is going to require six hours of charging, this is a deal killer for ANYTHING but a commuter that can be charged overnight and/or at work. And unless that electric 'second car' is going to be cheap, it is just not going to be worth buying for MOST people.

Ah, yes, I forgot! you can just pour liquid hydrogen in to your 10,000psi storage tank... wait a minute! the other day when I was filling up a 20lb propane tank (about 5 gallons) and it took a good 5 minutes to fill, and that was with a lower pressure liquid gas that has much larger molecules, so it's easier to pump, easier to seal connections, and safer because it's at a lower pressure, although a leak can still flash freeze your skin!

Now I know that charging batteries takes time, but when you look at the specs for the newer batteries, a slow charge time of 45 minutes, and quick charge of 15 minutes, and I couldn't find the spec sheet but I know that those same cells were speced at being able to take a 5 minute 80% charge, so in the same amount of time that it takes you to fill your gasoline car, and less time then it would take you to fill your hydrogen car you could charge your electric car, if only to 80%, spend a few more minutes and depending on the car, battery pack, and so on, you could travle 100+ miles on a charge, and have to stop for 5 minutes every 80 miles after that to recharge, to me, that is reasonable, it's not 400 miles, but really, how far can a fuel cell car travle? 150 miles on a fill up? hydrogen takes up alot of space even when compressed to 10,000psi.

[JanGeo]

Actually it takes me about 10 minutes to put a meer 10.5 gallons in my xB because the last gallon takes forever to go down the filler tube and all the mileage info I record. How many people take a 400 mile trip anyway? Mine are only 320 miles HA HA. BESIDES in most of our lifetimes there will NEVER be electric charging stations for our electric cars so don't worry about it.

[falstaff]

Originally Posted by StorminMatt

The reason why fuel cells are still around is that they have one distinct advantage over ANY type of rechargeable battery: you don't have to wait HOURS for the battery to recharge. You just refuel and go, just like a conventional car.

Wrong. Only a handful of H2 stations, and there won't be more than that for a very long time, if ever. Takes 21 tanker trucks of H2 to deliver the energy of one tanker of gas

Recharging time has ALWAYS been the BIG downfall of battery electric vehicles. I myself could live perfectly FINE with a vehicle that can only go 150-200 miles before recharging/refueling (I don't know why people care SO much about not being able to go 400+ miles without refueling). But if it is going to require six hours of charging, this is a deal killer for ANYTHING but a commuter that can be charged overnight and/or at work. And unless that electric 'second car' is going to be cheap, it is just not going to be worth buying for MOST people.

As for the fuel cells themselves, their efficiency (at around 50-60%) leaves something to be desired. After all, this level of efficiency can be achieved by gas turbines.

Wrong. No heat engine exceeds Carnot efficiency of ~40%, including gas turbines.

And gas turbines last a LONG time (compared to fuel cells and, for that matter, reciprocating engines). They can also burn a wide variety of fuels (including biodiesel and straight vegetable oil). But keep in mind a couple of things. First of all, this is really not much less than NiMH batteries. And NOBODY talks about how inefficient NiMH batteries are. And secondly, fuel cell technology is VERY much in its infancy

Wrong

(even compared to more advanced gas turbines). Efficiency has increased by quite a bit over even a few years ago. And I would suspect that it will imcrease further in the future.

Hydrogen production, on the other hand, is a BIGGER issue. Simply put, we really do not have a good way to make it. One way is from fossil fuels, either directly or by electrolysis of water using electricity made by burning fossil fuels. Neither of these methods are very efficient. And when combined with all the other losses in the entire hydrogen cycle, you are probably better off just burning the fossil fuels in a regular car like we do today. Another thing that few people consider is that if EVERYONE starts using grid power to make hydrogen, the grid will just not be able to handle it without large upgrades and additional power plants. So along with the greater inefficiency will come large infrastructure costs. You are beginning to see that this is not such a hot idea from the supply side.

So what about using wind and/or solar power to make hydrogen? In theory, it is an EXCELLENT idea. BUT, how much power is currently generated by wind and solar? I can't quote exact figures. But I believe it is well under 10%. In other words, we couldn't hope to make a dent in the current demand for energy to power vehicles with hydrogen made from wind and/or solar power (or other renewables, for that matter). And nothing short of a breakthrough in terms of drastically lowered cost of photovoltaics is going to change that. Now if we ever see photovoltaics at $.50 per watt, hydrogen will look ALOT more attractive. But I personally see higher fuel cell efficiency happening before THAT happens.