Foo - Chemists - How much energy does it take to make hydrogen?

Just a quick thought. Wouldn't it be cool if your trainer at home wasn't a fluid or magnetic trainer but one based on creating hydrogen? As you turn the pedals you create the current to split water into hydrogen and oxygen. I think it'd be real neat if the trainer was then attached to a device to capture the hydrogen.

Is hydrogen the energy answer though? If it is, I think this would be a nice way to get it. Individuals would be responsible for their energy needs and ultimately societies fitness levels would benefit as well. Wouldn't it be cool if you went over to your neighbor and asked, "hey, you got any hydrogen I can borrow?" If we could produce even just 100 watts for an hour on a trainer, would this be able to create enough hydrogen to power a car for 50 miles?

Just a thought.

PS - This idea was inspired by Specializeds innovate or die campaign on their website. Their demo innovation was a simple dc generator attached to a trainer that went to an ac inverter to make power for a computer. I just tweaked the idea a bit. http://www.innovate-or-die.com/
(http://www.innovate-or-die.com/)

I ain't no chemist or physicist or nuthin', but wouldn't you have to have a fusion reactor to make use of the hydrogen for energy purposes? If so, it would take one hell of a rider to produce any measureable energy at all, as it takes a whooooole bunch of energy (like a serious laser - and I mean serious laser) to get hydrogen to fuse into helium, not to mention all the containment problems. And even thenn, I don't think anyone has achieved "break even" yet (where ytou get as much useable energy out of the reaction as you put into making it happen).

Of course, I could be wrong or outdated. Phantomcow2, consider researching this to be your next homework assignment, due Monday.

or you could run an alternator off the trainer and store the electricity in a battery.
Average person could probably do between 100 and 200 watts for an hour. This could be stored in a deep cycle 12V battery, and if you needed 110volts, hook up a modified sine wave converter, and voila 110v AC current.

Heat energy:
1 kilo watt hour of electricity = 3413 BTU
1 gallon gasoline = 125,000 BTU

Most riders generate around 0.2 KW (200 watts). 682 BTU per hour.

You could run your TV with the bike power, though.

or you could run an alternator off the trainer and store the electricity in a battery.
Average person could probably do between 100 and 200 watts for an hour. This could be stored in a deep cycle 12V battery, and if you needed 110volts, hook up a modified sine wave converter, and voila 110v AC current.

Yea that just struck my head too. Some questions I would have however are, is that the most efficient way to store the energy. The problem with batteries is they take forever to build up and can only store so much energy. That's why a lot of the 100% electric cars of today only have ranges of at most 300 miles and then need hours to recharge. You're also limited by the size of the battery you're using. Whereas if you split the hydrogen and oxygen you can store the hydrogen immediately and you're only limited by the size of the tank you put it in. Say you had a tank the size of a water heater in your house, I predict that would be able to more cheaply store more energy than an expensive battery that could hold similar amounts of energy.

This is where we need chemists and physicists to chime in. I understand energy is lost when you transfer it from one form to another, but I think splitting water into hydrogen would be more efficient than storing directly in a battery. Plus I think it'd be cool if then you could decide what you want the energy to be used for. Do you heat your house? Power your vehicle? Heat your pool? Run a power generator?

Heat energy:
1 kilo watt hour of electricity = 3413 BTU
1 gallon gasoline = 125,000 BTU

Most riders generate around 0.2 KW (200 watts). 682 BTU per hour.

You could run your TV with the bike power, though.

A small LCD screen or your PC. You could even run lights in the house if they are low wattage, high efficiency type like LED lights.

Heat energy:
1 kilo watt hour of electricity = 3413 BTU
1 gallon gasoline = 125,000 BTU

Most riders generate around 0.2 KW (200 watts). 682 BTU per hour.

You could run your TV with the bike power, though.

This is where I get confused, because yes one kwh is 3413. Alright, how much hydrogen can you produce from water with 682 btu per hour? I see the hydrogen as being stored energy just as oil is. So while you produce only 682 btu's, you create x amount of hydrogen which holds maybe 50,000 btu's. You're not creating energy since the energy was always there in the water. Sort of like how a small spark in a gas engine releases a lot of energy in the gasoline.

It requires energy to split water into hydrogen and oxygen. You get about the same energy back when you burn the hydrogen, creating water again.

It's really no different than charging a battery.

I'm no chemist, but I know that if I eat a burrito before I hop on the trainer, I'll liberate more methane than pure hydrogen. :p :D

This is where I get confused, because yes one kwh is 3413. Alright, how much hydrogen can you produce from water with 682 btu per hour? I see the hydrogen as being stored energy just as oil is. So while you produce only 682 btu's, you create x amount of hydrogen which holds maybe 50,000 btu's. You're not creating energy since the energy was always there in the water. Sort of like how a small spark in a gas engine releases a lot of energy in the gasoline.

You can't burn water, and no intermediate compound can change that.

http://www.science.uwaterloo.ca/~cchieh/cact/c120/hess.html

You could make a nice battery charger with a trainer, one would think. Rectifier - regulator - charger - battery. Unfortunately your cell phone manufacturers charger might need to include the generator into its control loop.

You can't burn water, and no intermediate compound can change that.

http://www.science.uwaterloo.ca/~cchieh/cact/c120/hess.html

We're not burning water. I forgot the name of the process but have it now; electrolysis (http://en.wikipedia.org/wiki/Electrolysis). "Electrolysis is a method of separating bonded elements and compounds by passing an electric current through them."

So that's my question. If an avg cyclist could produce 100-200 watts of electricity over an hour. How much hydrogen would they be able to make through electrolysis?

We're not burning water. I forgot the name of the process but have it now; electrolysis (http://en.wikipedia.org/wiki/Electrolysis). "Electrolysis is a method of separating bonded elements and compounds by passing an electric current through them."

So that's my question. If an avg cyclist could produce 100-200 watts of electricity over an hour. How much hydrogen would they be able to make through electrolysis?

You're still trying to burn water indirectly by making an intermediate compound (hydrogen).

If you want to know how much hygrogen gas you could make from 200W it's less than 5g/hour
water Hf = -285.8KJ/mol
1W = 1J/s
200J/s x 3600s/hour = 720,000J/hour
720,000J/hour / 285,800J/mol = 2.5mol/hour
2.5mol/hour x 2g/mol = 5g H2/hour

Oh oh and hook up the oxygen to a face mask, make some fuel, and have an oxygen bar, AND exercise.
;)

What might make more sense is to generate electricity which you put into your house panel. So while you're using the bike your offsetting the power used from the grid by what you make on the bike. (assuming this is all possible)

I promise you it is possible to burn water. Inside water is stored energy, in the form of hydrogen. What electrolysis does is put energy in to extract that stored energy. Unfortunately, it requires more energy to put in than you actually extract. Stan Meyers developed a system, which has been replicated, which makes this untrue. http://www.youtube.com/watch?v=bqfiAXIs3Xc&mode=related&search=
http://www.youtube.com/watch?v=u9XrLOudwRw&mode=related&search=
http://www.hotlinkfiles.com/browse/waterfuel/42765

http://befreetech.com/media/stan_meyers_bb.wmv

Hydrogen is a very viable energy source. It improves the performance of ICE's greatly. The key is probably not to store the hydrogen, but to generate it on demand.

And it's definitely possible to run some electrolysis using your trainer. In fact, you should simply remove whatever device you have to generate resistance and replace it with a good sized motor, or a car alternator. Use your energy to drive that alternator.
When you are on the trainer, that's wasted energy. Harness it all!

By the way, 200watts is a decent amount, assuming you're talking 200 electrical watts. I ran some electrolysis experiments at home and got great results with 200 watts. I believe it is the amperage that counts more tahn the voltage though. By the way, the Stan Meyer system does not require any electrolyte in the water.

I promise you it is possible to burn water. Inside water is stored energy, in the form of hydrogen. What electrolysis does is put energy in to extract that stored energy. Unfortunately, it requires more energy to put in than you actually extract. Stan Meyers developed a system, which has been replicated, which makes this untrue. http://www.youtube.com/watch?v=bqfiAXIs3Xc&mode=related&search=
http://www.youtube.com/watch?v=u9XrLOudwRw&mode=related&search=
http://www.hotlinkfiles.com/browse/waterfuel/42765

http://befreetech.com/media/stan_meyers_bb.wmv

Hydrogen is a very viable energy source. It improves the performance of ICE's greatly. The key is probably not to store the hydrogen, but to generate it on demand.

You're not burning water; you are obtaining the energy you chemically stored in the form of hydrogen.

Why do people ask questions if they are just going to ignore the answer because it doesn’t fit their fairy tale? Read the Hess law link I provided.

the amount of food and water you would need to consume, to create any usable amount of hydrogen, would offset any benefit. net result would be negative impact on resources

What might make more sense is to generate electricity which you put into your house panel. So while you're using the bike your offsetting the power used from the grid by what you make on the bike. (assuming this is all possible)Sure it's possible. You can get a solar-power system for your house and use your trainer to charge the batteries as well. Regulations in a lot of areas require you to hook up that system to the local power-grid and sell them your excess power-generation at a discount.

You're not burning water; you are obtaining the energy you chemically stored in the form of hydrogen.

Why do people ask questions if they are just going to ignore the answer because it doesn’t fit their fairy tale? Read the Hess law link I provided.

I’m done with you morons.

Phantom is right in that you can electrolyze water to produce hydrogen. And you are right in that you are essentially supplying the gibbs free energy to release the calorific value of hydrogen. Everybody chill K

I violently attack ignorance in all its forms.

Nobody doubts you can make hydrogen gas from water, or burn hydrogen gas. It’s this free energy hippie crap that annoys me.

How about this?

Assuming you can produce 682 BTU per hour and there is no loss in the electro-mechanical electrolysis system, you will produce X amount of hydrogen per hour. However, X amount of hydrogen will only give you back 682 BTU in the ideal (i.e. not real world) situation. To that effect, hydrogen is only acting as a storage mechanism.

In real life, the efficiency of conversion is not unity so there will be losses in the conversion from water to its elements of hydrogen and oxygen. Burning hydrogen for energy via heat is also very inefficient, and you will have significant losses there also. Finally, hydrogen and oxygen are gases. That means storage is quite challenging. If you want to have efficient storage, you need to compress them. Obviously, the compression, and then subsequent decompression prior to use also do not score well on the efficiency chart. In the end, really, hydrogen as a fuel is really more or less a pipe dream now.

Having said that, I read somewhere that someone is researching on how to get plants to produce hydrogen gas directly from photosynthesis. Essentially, they are attempting to use genetically engineered plants to produce hydrogen gas using sunlight. You still have the storage/compression/decompression loss but it makes hydrogen as a fuel a little more feasible.

(Suggestion: Please read up on thermodynamics)

the amount of food and water you would need to consume, to create any usable amount of hydrogen, would offset any benefit. net result would be negative impact on resources

But since you would have been on the trainer anyways, those resources have already been used.

How about this?

Assuming you can produce 682 BTU per hour and there is no loss in the electro-mechanical electrolysis system, you will produce X amount of hydrogen per hour. However, X amount of hydrogen will only give you back 682 BTU in the ideal (i.e. not real world) situation. To that effect, hydrogen is only acting as a storage mechanism.

In real life, the efficiency of conversion is not unity so there will be losses in the conversion from water to its elements of hydrogen and oxygen. Burning hydrogen for energy via heat is also very inefficient, and you will have significant losses there also. Finally, hydrogen and oxygen are gases. That means storage is quite challenging. If you want to have efficient storage, you need to compress them. Obviously, the compression, and then subsequent decompression prior to use also do not score well on the efficiency chart. In the end, really, hydrogen as a fuel is really more or less a pipe dream now.

Having said that, I read somewhere that someone is researching on how to get plants to produce hydrogen gas directly from photosynthesis. Essentially, they are attempting to use genetically engineered plants to produce hydrogen gas using sunlight. You still have the storage/compression/decompression loss but it makes hydrogen as a fuel a little more feasible.

(Suggestion: Please read up on thermodynamics)

Beautiful +100

And of course you're not burning water, you're burning the components of water. It just happens to be that burning said components offer several benefits. Zero negative emissions, and better efficiency in the combustion engine.

I promise you it is possible to burn water.

Why did you spew this crap then.

But since you would have been on the trainer anyways, those resources have already been used.

Agreed. Surly you could save that energy, but best way would be a battery or a capacitor.

Read:
http://waterpoweredcar.com/stan.html

Also, getting a hydrogen generator coupled with your current gasoline fuel injected engine can offer excellent results. Even though the generation of hydrogen through conventional electrolysis is not completely efficient, the net gain after you insert it into a vehicle is positive. You can get 50% more fuel economy with this. It's not enough to completely get off you off dead dinosaur, but it's a start.
For those who think it's junk science, please explain why there are patents for this. Also, please explain why a company with actual stock (symbol HYPF) completely focuses on using hydrogen to boost efficiency.

Also, check out Roy McAllister:
http://www.youtube.com/watch?v=fCI4WuCpZPE&mode=related&search=

It's not "free" energy, it's efficient and modern means of extracting it.

Why did you spew this crap then.

Misspoke.

Read:
http://waterpoweredcar.com/stan.html

Also, getting a hydrogen generator coupled with your current gasoline fuel injected engine can offer excellent results. Even though the generation of hydrogen through conventional electrolysis is not completely efficient, the net gain after you insert it into a vehicle is positive. You can get 50% more fuel economy with this. It's not enough to completely get off you off dead dinosaur, but it's a start.
For those who think it's junk science, please explain why there are patents for this. Also, please explain why a company with actual stock (symbol HYPF) completely focuses on using hydrogen to boost efficiency.

Also, check out Roy McAllister:
http://www.youtube.com/watch?v=fCI4WuCpZPE&mode=related&search=

It's not "free" energy, it's efficient and modern means of extracting it.

I could entertain the notion that external hydrogen could increase the energy conversion efficiency of another fuel source. However, I do not think one could create a practical system. This would be akin to installing a small steam engine in your tailpipe to absorb waste heat...

Check out this replication of Stan Meyers fuel cell:
http://www.youtube.com/watch?v=u9XrLOudwRw&mode=related&search=

That's only drawing .5amps, he gives a wattage. You would probably have to put in 10amps for typical electrolysis if you wanted that kind of production.

It requires energy to split water into hydrogen and oxygen. You get about the same energy back when you burn the hydrogen, creating water again.

It's really no different than charging a battery.

+1

However, if storing the energy as hydrogen ready to be burned ends up being more efficient than storing it in a battery, that would be good.

Unfortunately, we don't really use hydrogen for anything around the house yet, so I doubt converting mechanical energy to electrical energy to chemical energy back to electrical energy would be at all efficient. If we had hydrogen powered cars or household appliances, it would be a different story. Perhaps in a few years, but for today, just charge batteries.

computers use DC, can just eliminate the inverter and run the computer with DC alone and get rid of the power loss involved with the inverter. running through the inverter to provide AC and then back through the power supply for the computer to get DC you have two places you lose power that you don't need in the system.

A generator is a good move. Making the wheel HEAVY will improve the flywheel effect and keep power output steady, Great excersize. Had a similar rig on my sailboat for a while to recharge the house batteries, often times a long sail is FILLED with slack time, so I rigged a bicycle to run the generator so I could sit back and read while charging batteries, worked great, everythng was run from 12v so I didn't use inverters.

Ken.

And by the way, a pure hydrogen burning engine can be used as a humanitarian relief tool. THis would make it worth it whatever the inefficiencies are.

You have a tank of hydrogen gas feeding an ICE. The output shaft turns a generator, so you have electricity for life support units, lights, whatever.
The exhaust water vapor can be condensed and turned into pure drinking water.
The waste heat can be used as a heat source, or even for cooking.

And by the way, a pure hydrogen burning engine can be used as a humanitarian relief tool. THis would make it worth it whatever the inefficiencies are.

You have a tank of hydrogen gas feeding an ICE. The output shaft turns a generator, so you have electricity for life support units, lights, whatever.
The exhaust water vapor can be condensed and turned into pure drinking water.
The waste heat can be used as a heat source, or even for cooking.

Yea it's not always about how 'efficient' a system is in physical terms. Sometimes it's about just using what ya got. Sort of like how instead of the engines in cars just moving cars, they also are the heaters. Considering how scarce drinking water can be in some areas, I'm sure many third world countries wouldn't mind making hydrogen if it meant getting clean water.

How are you going to get all this pure hydrogen in an energetically favorable manner? Pure hydrogen is not exactly abundant. The best way to make it is from electrolysis of water, but you might as well just give them the clean water that you would have electrolyzed and the energy source you would have wasted creating hydrogen with less energy content than the energy source you would have used up.

Seriously, there are no magic bullet energy solutions. If there were, the authors would have long since published in a peer reviewed format and sold their patents for billions. And there are no ways to defeat thermodynamics. All principles of thermodynamics can be deduced from counting principles. So the burden of proof most definitely is on the inventor/discoverer. Unless peer reviewed, bull solid waste.

How are you going to get all this pure hydrogen in an energetically favorable manner? Pure hydrogen is not exactly abundant. The best way to make it is from electrolysis of water, but you might as well just give them the clean water that you would have electrolyzed and the energy source you would have wasted creating hydrogen with less energy content than the energy source you would have used up.

Seriously, there are no magic bullet energy solutions. If there were, the authors would have long since published in a peer reviewed format and sold their patents for billions. And there are no ways to defeat thermodynamics. All principles of thermodynamics can be deduced from counting principles. So the burden of proof most definitely is on the inventor/discoverer. Unless peer reviewed, bull solid waste.


Well a lot of electrolysis machines don't use pure distilled water. Salt water is a viable water option. Granted I don't think muddy water or likewise dirty water would work. For some NGO it might be worth a look though.

I never expected a magic bullet energy solution. I was just wondering if it's possible to take the energy I'm already making on a trainer and make it more useful than just giving me rippling guads. I don't care about only being 50% efficient in the system. Hell, if I could be on a trainer for an hour a night to produce enough hydrogen or battery power to have a scooter/motorcycle that could travel 50-100 miles wouldn't you at least consider it? That's all I want to do. Just think about the millions of watts being wasted in the trainers being used by cyclists right now.

Even just for personal use as I mentioned I want, what kind of impact on the environment do you think it would have if just a million cyclists did the same? Or what if people started doing it because of the energy benefits, and not because they're cyclists. I imagine the system would be cheaper and easier to install than solar and wind systems. Just the little bit here and there, but with millions of people, can go a long way.

Think about how far you would have travelled on a bike if you had spent that time on the road instead. Given perfect efficiency (which you won't achieve, but it lets us estimate a theoretical maximum), that's all you'd manage storing the energy you put in on a trainer, assuming your scooter/motorcycle weighed as little as your bicycle weighs.

Let's put some numbers to things, shall we? Let's say I ride at the highest sustainable effort I can do on my trainer for one hour. No fan blowing or anything like that to waste energy. Let's assume I manage about 250 watts. (In reality, I doubt I could sustain 250 watts for an hour, and definitely not on a trainer with no fan blowing.) That's about 1/3 horsepower. Assuming perfect efficiency, I can power a 5 horsepower go-kart for all of 1/15 hour, or 4 minutes. In reality, even achieving 50% efficiency probably would be tough on a small scale system of this sort (consider inefficiencies in electrical storage AND in power generation), so maybe 2 minutes. Never mind the energy cost of installing such an implementation in the first place. And all this is pretty much best case scenario.

Just get a straw from here to some planet with hydrogen in it's atmosphere and suck on it.

http://www.masgrafx.com/masgrafxracing/modules/Downloads/shots/temp/3394.jpg

Let's put some numbers to things, shall we? Let's say I ride at the highest sustainable effort I can do on my trainer for one hour. No fan blowing or anything like that to waste energy. Let's assume I manage about 250 watts. (In reality, I doubt I could sustain 250 watts for an hour, and definitely not on a trainer with no fan blowing.) That's about 1/3 horsepower. Assuming perfect efficiency, I can power a 5 horsepower go-kart for all of 1/15 hour, or 4 minutes. In reality, even achieving 50% efficiency probably would be tough on a small scale system of this sort (consider inefficiencies in electrical storage AND in power generation), so maybe 2 minutes. Never mind the energy cost of installing such an implementation in the first place. And all this is pretty much best case scenario.

That's where again I'm confused and enthalpic confused me further when he replied with, "If you want to know how much hygrogen gas you could make from 200W it's less than 5g/hour
water Hf = -285.8KJ/mol
1W = 1J/s
200J/s x 3600s/hour = 720,000J/hour
720,000J/hour / 285,800J/mol = 2.5mol
2.5mol x 2g/mol = 5g H2/hour"

I don't know really what that all means. 5 grams of H2 an hour?

My question, which I'm sure someone has answered but I haven't understood, is:

Is it not the case that water contains 2 Hydrogen atoms. Good so far. Hydrogen atoms contain X amount of energy. My 200 watts over an hour produces the energy only to get to that X amount of energy in the hydrogen and not actually use it. And I can see now where I'm getting flawed. If I can use 200 W to access 201 W it's a perpetual motion machine, ie impossible.

Where is the difference in gasoline then? How is that process different? It sounds very awkward to me that even after the billions of dollars/energy used to find oil, drill for it, transport it, refine it, transport again, then use in vehicles that it still gives us useful energy output. I don't see how.

Yea this whole "perpetual motion machine" is a bunch of bull. The gasoline process is no different. On NPR I remember hearing something like it takes 2 or 3 barrels of oil to produce 1 barrel for your car.

Stanley Meyer found a more efficient way to extract the energy in water. You can youtube it, it's amazing to see.

We're not burning water. I forgot the name of the process but have it now; electrolysis (http://en.wikipedia.org/wiki/Electrolysis). "Electrolysis is a method of separating bonded elements and compounds by passing an electric current through them."

So that's my question. If an avg cyclist could produce 100-200 watts of electricity over an hour. How much hydrogen would they be able to make through electrolysis?

From my CRC Handbook of Chemistry and Physics I get 318.8 BTU as the optimum energy value of one cubic foot of Hydrogen at standard temp. and pressure. Per earlier posters that gives 2 cubic feet of H2 per hour or enough for a nice big balloon. Given those evil Laws of Thermodynamics you are likely to get enough hydrogen for one nice small balloon, preferably red. Or one or two cylinder volumes in a car engine. Sorry, no 50 mile rides in a car here. The dynamics of pedal to generator to battery are pretty much worked out. You might be able to put a 5 person quint bike on a generator to power one persons' electric bike. Again, Que Sera Sera.

Science blows.

PC2, look up the concept of a state function and the energy of water. There is no non-nuclear chemical energy to be extracted from water. Period. Nothing you do can change that. If you find an exception that can withstand peer review from the scientific community at large, submit it for peer review, and I'll guarantee you a Nobel Prize within 3 years (if not sooner). After all, Hess's Law guarantees you a perpetual motion machine if you can pull it off.

permanentjuan, you don't have a closed loop with oil. You get <stuff> going to CO2 and H2O. Something actually changes from the beginning to the end. In the stuff PC2 is reading about, you're getting H2O going to H2O. There is no energy to be gained there since nothing changes. Only energy losses due to inefficiencies.

I am all for trying to make big discoveries to better the world. After all, I'm devoting my career to research and teaching. But one must pick one's battles, and picking battles against thermodynamics is not a good way to make progress.

But one must pick one's battles, and picking battles against thermodynamics is not a good way to make progress.

Homer said something about this.

Here's my recommendation:

Please take some time and effort to familiarize yourself with the basic concepts of thermodynamics before attempting to constructively participate in this thread. A lot of the confusion and questions being stated will have obvious answers once you do that. Plus, it is much easier to ask clarifying questions when you have at least an inkling of the concept of energy conservation. (no, this is not nuclear science we're discussing)

PS: I've visited Stan's site and can categorically state that it is misleading at best. I won't spend the effort debunking it because if you follow the above recommendation, it will become clear to you why.