R-Squared Energy Blog

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The Hydrogen Electrolyzer Debunked?

Popular Mechanics just ran the tests and reported on the results:

Water-Powered Cars: Hydrogen Electrolyzer Mod Can’t Up MPGs

I have told people not to waste their money, but that is just based on the science: It takes more energy to electrolyze water than you get back out of it. In theory, injecting hydrogen could allow you to run at a different compression ratio, which could allow you to derive more useful work out of the engine. Or, it could allow you to run at a different fuel/air ratio. So I don’t necessarily reject it out of hand until I have seen the data, I am just highly skeptical. Popular Mechanics provides some data. The background:

Water-powered cars continue to be the largest single topic taking over my in box—and the Comments section of this Web site. And it’s not just my recent column on the truth about water-chugging prototypes. This trend has become an obsession with many backyard inventors, and some of them have become quite strident, insisting that if I knew anything at all about cars, I’d be embracing this technology. They say it could help change the world as we know it. They even say it could eliminate the energy crisis altogether.

So, last month I received an electrolyzer, fabricated by my old Monster Garage partner, Steve Rumore at Avalanche Engineering out in Colorado. Steve cleverly designed the device into a steel toolbox, making it portable—just the ticket for someone tinkering with HHO/water/hydrogen/Brown’s Gas­powered conveyances. The unit consists of eight plastic bottles with stainless-steel electrodes, connected up in series—parallel to the vehicle’s battery. The cells are filled with plain ol’ water and a small amount of potassium hydroxide electrolyte to conduct electricity. A hose conveys the HHO output to the engine.

It took me a few days of puttering around in my shop to get the electrolyzer up and running. I’m using an HKS Camp 2 onboard computer, hooked into an LCD monitor that’s suction-cupped to the windscreen, to check things like mass airflow, fuel-injector pulse width, battery voltage and, of course, fuel economy.

But guess what? My fuel economy is exactly the same, whether the HHO generator is turned on or not. And that’s exactly what I expected. This isn’t anecdotal evidence from several tankfuls of gasoline. It’s steady-state, flat-road testing, and I don’t even pretend to have actual economy numbers. I’m using fuel-injector pulse widths directly from the OBD II port. That means I’m measuring the actual time the injectors are open and delivering fuel. When the HHO generator is toggled on, there’s no change. And when it’s turned back off, there’s no change. Well, the computer’s system voltage sags a couple of tenths of a volt, indicating the current drain to run the electrolyzer.

This is not a great surprise, but it didn’t take long for someone in the comments section following the article to invoke the oil conspiracy charge:

As an owner of an auto repair facility that installs and configures HHO Cells i have to disagree with your findings. I am not surprised by your results considering your methods and your obvious opinion going in that it would never work. It does in fact work when installed and configured correctly. Your article brings to mind the weak attempt Mythbusters described on their show. Needless to say my high opinion of Popular Mechanics and MythBusters is not so anymore. By the way, i wouldn’t be surprised if the oil companies financed your obviously biased experiment.

Of course I have to point out that since the commenter installs and configures HHO cells, he has a vested interest in claiming that they work. One good accusation deserves another.

August 8, 2008 Posted by | water car | 31 Comments

Fire from Water

Based on some of the comments following my post on the “water car”, I think several people misunderstood the point. It was not to debunk the water car. You can in fact run a car with water as one of the reactants. I could even run a car on crushed ice or Jell-O, if I used the right second reactant.

My point was merely to show how a car could be run on water, and to further point out that it requires a second, very reactive substance. In other words, the “water car” is not running solely on water. The other point was that the reactive substance will always take more energy to produce than you will get back from splitting the water. That’s simply pointing out the thermodynamics. It doesn’t mean that there might not be times that it makes economic sense to do this – just that there is much more to the story than a car that runs on water.

Keeping with that theme, here are some videos showing how water can react with various metals/compounds to produce fire – and this should give you an indication of what’s happening in the water car.

First up, if you put lithium (or any of several other alkali metals) in water, it reacts explosively. Hydrogen is evolved, and so much heat is produced that the hydrogen ignites:

Lithium + Water = Fire

Second is a reaction I have known of for over 30 years. When I was growing up in Oklahoma, we often went hunting at night. I had a carbide lamp that I used to produce light. The way it worked is that I would put solid calcium carbide pellets (CaC2) in a bottom compartment, and water in the top compartment. The water dripped on the calcium carbide and formed acetylene (C2H2) according to the following reaction:

CaC2 + 2 H2O → C2H2 + Ca(OH)2

Of course acetylene is quite flammable, and this was burned to produce the light for our hunts. Much like the “water car”, I had a “water lamp.” (In fact, one time the lamp caught on fire on top of my head; so there are some safety considerations). One thing to point out is that it takes a lot of energy to make calcium carbide. This is the energy you get back when you burn the acetylene, but it is never as much energy as it took to make the calcium carbide in the first place. Here is a demonstration of someone lighting a carbide lamp.

Water + Calcium Carbide = Fire

The moral? The water car isn’t such a mystery, if you understand a little bit about the chemistry. The question is whether a water car can be cost competitive, given the need for the second reactant. My suspicion is that it will usually be more cost effective to use energy to run a PHEV than to use energy to produce a metal compound that will react with water to run a water car. The reason I say that is that you can’t escape the energy inputs for making the metal compound, and that energy is most efficiently used directly in the car, rather than via the water intermediate.

Note: Following this post, my Internet access is going to be disconnected, and then I will be on the road until Friday night. Responses will be infrequent.

June 18, 2008 Posted by | chemistry, water car | 32 Comments

Fire from Water

Based on some of the comments following my post on the “water car”, I think several people misunderstood the point. It was not to debunk the water car. You can in fact run a car with water as one of the reactants. I could even run a car on crushed ice or Jell-O, if I used the right second reactant.

My point was merely to show how a car could be run on water, and to further point out that it requires a second, very reactive substance. In other words, the “water car” is not running solely on water. The other point was that the reactive substance will always take more energy to produce than you will get back from splitting the water. That’s simply pointing out the thermodynamics. It doesn’t mean that there might not be times that it makes economic sense to do this – just that there is much more to the story than a car that runs on water.

Keeping with that theme, here are some videos showing how water can react with various metals/compounds to produce fire – and this should give you an indication of what’s happening in the water car.

First up, if you put lithium (or any of several other alkali metals) in water, it reacts explosively. Hydrogen is evolved, and so much heat is produced that the hydrogen ignites:

Lithium + Water = Fire

Second is a reaction I have known of for over 30 years. When I was growing up in Oklahoma, we often went hunting at night. I had a carbide lamp that I used to produce light. The way it worked is that I would put solid calcium carbide pellets (CaC2) in a bottom compartment, and water in the top compartment. The water dripped on the calcium carbide and formed acetylene (C2H2) according to the following reaction:

CaC2 + 2 H2O → C2H2 + Ca(OH)2

Of course acetylene is quite flammable, and this was burned to produce the light for our hunts. Much like the “water car”, I had a “water lamp.” (In fact, one time the lamp caught on fire on top of my head; so there are some safety considerations). One thing to point out is that it takes a lot of energy to make calcium carbide. This is the energy you get back when you burn the acetylene, but it is never as much energy as it took to make the calcium carbide in the first place. Here is a demonstration of someone lighting a carbide lamp.

Water + Calcium Carbide = Fire

The moral? The water car isn’t such a mystery, if you understand a little bit about the chemistry. The question is whether a water car can be cost competitive, given the need for the second reactant. My suspicion is that it will usually be more cost effective to use energy to run a PHEV than to use energy to produce a metal compound that will react with water to run a water car. The reason I say that is that you can’t escape the energy inputs for making the metal compound, and that energy is most efficiently used directly in the car, rather than via the water intermediate.

Note: Following this post, my Internet access is going to be disconnected, and then I will be on the road until Friday night. Responses will be infrequent.

June 18, 2008 Posted by | chemistry, water car | 31 Comments

How to Run a Car on Water

Oh, it can be done. There are no scientific laws that say you can’t run a car on water. In fact, a Japanese company is the latest to claim they have pulled it off. See the video here:

Water-fuel car unveiled in Japan

However, what you can’t do is run a car on water without energy inputs greater than you get from splitting the water. In simple terms, let’s say you split water to create 10 BTUs of hydrogen. You can then use that to burn in the car, or to operate a fuel cell. When you burn the hydrogen, it reacts with oxygen to again form water. But if you want to take the water and turn it back into hydrogen, it will always take more than the 10 BTUs that you released in the first place.

So let’s say it takes 12 BTUs of input to produce 10 BTUs of hydrogen from water. What’s wrong with that? Well, why wouldn’t you just use those 12 BTUs directly, instead of going through the step of cracking the water? This would be sort of like using gasoline in your car to produce steam to drive a steam engine that actually runs the car. But it’s a lot more efficient to cut out the middleman and use the gasoline directly. (One possible exception is if the conversion allowed you to operate a more efficient motor; say an electric motor instead of an internal combustion engine).

There is a way to mask the energy input, and that is what the Japanese company is doing. I had to do a bit of research, but I finally found this:

Genepax unveils water energy fuel cell system

Within the story is the key to what’s going on:

Though the company did not reveal any more detail the company president said that they had “succeeded in adopting a well-known process to produce hydrogen from water to the MEA”, similar to the mechanism that produces hydrogen by a reaction of metal hydride and water.

That clued me in as to how they were pulling this off. Metal hydrides will react with water to produce hydrogen. For instance, sodium hydride (NaH) reacts spontaneously with water as follows:

NaH + H2O → H2 (gas) + NaOH ΔH = −83.6 kJ/mol, ΔG = −109.0 kJ/mol

So, if you had NaH in your car, and you dripped water on it, you would produce hydrogen from the water. What’s the catch? Metal hydrides that react with water don’t occur naturally, because they would have already reacted. This is the same reason hydrogen doesn’t occur naturally on earth. So, it takes energy inputs to make the metal hydrides. And there is the hidden energy source in the water car.

Here’s what the laws of thermodynamics tell you. Back to the 10 BTUs of energy we liberated for the water car; it would have taken well more than 10 BTUs to produce the metal hydride required for that reaction. (Note that they may not be using metal hydrides; there are other compounds that react with water to liberate hydrogen. Again, none occur naturally on earth, and all require significant energy inputs to produce).

So, the moral is: Sometimes it appears that the lunch is free, but the bill eventually comes anyway – when you have to replenish the catalyst.

June 16, 2008 Posted by | hydrogen, water car | 42 Comments

How to Run a Car on Water

Oh, it can be done. There are no scientific laws that say you can’t run a car on water. In fact, I have personally made fire from water on a number of occasions. A Japanese company is the latest to claim they are running a car on water. See the video here:

Water-fuel car unveiled in Japan

However, what you can’t do is run a car on water without overall energy inputs greater than you get from splitting the water. In simple terms, let’s say you split water to create 10 BTUs of hydrogen. You can then use that to burn in the car, or to operate a fuel cell. When you burn the hydrogen, it reacts with oxygen to again form water. But if you want to take the water and turn it back into hydrogen, it will always take more than the 10 BTUs that you released in the first place.

So let’s say it takes 12 BTUs of input to produce 10 BTUs of hydrogen from water. What’s wrong with that? Well, why wouldn’t you just use those 12 BTUs directly, instead of going through the step of cracking the water? This would be sort of like using gasoline in your car to produce steam to drive a steam engine that actually runs the car. But it’s a lot more efficient to cut out the middleman and use the gasoline directly.

There are two possible scenarios in which this sort of scheme might make sense. One is if the conversion allowed you to operate a more efficient motor; say an electric motor instead of an internal combustion engine. The second is when it is more convenient to keep the fuel in a solid form, as was the case for my carbide lamp example. Since the fuel is only produced when water drips on the solid, there isn’t a large inventory of flammable gas or liquid that can catch fire or explode.

However, it is important to keep in mind that there is a catch. There is a way to mask the energy input, and that is what the Japanese company is doing. I had to do a bit of research, but I finally found this:

Genepax unveils water energy fuel cell system

Within the story is the key to what’s going on:

Though the company did not reveal any more detail the company president said that they had “succeeded in adopting a well-known process to produce hydrogen from water to the MEA”, similar to the mechanism that produces hydrogen by a reaction of metal hydride and water.

That clued me in as to how they were pulling this off. Metal hydrides will react with water to produce hydrogen. For instance, sodium hydride (NaH) reacts spontaneously with water as follows:

NaH + H2O → H2 (gas) + NaOH ΔH = −83.6 kJ/mol, ΔG = −109.0 kJ/mol

So, if you had NaH in your car, and you dripped water on it, you would produce hydrogen from the water. What’s the catch? Metal hydrides that react with water don’t occur naturally, because they would have already reacted. This is the same reason hydrogen doesn’t occur naturally on earth. So, it takes energy inputs to make the metal hydrides. And there is the hidden energy source in the water car. The car isn’t really running on water. It is running on a combination of water and a very reactive compound that must be replenished.

Here’s what the laws of thermodynamics tell you. Back to the 10 BTUs of energy we liberated for the water car; it would have taken well more than 10 BTUs to produce the metal hydride required for that reaction. (Note that they may not be using metal hydrides; there are other compounds that react with water to liberate hydrogen. Again, none occur naturally on earth in the reactive form, and all require significant energy inputs to produce).

So, the moral is: Sometimes it appears that the lunch is free, but the bill eventually comes anyway – when you have to replenish the catalyst. (Note: As others have correctly pointed out, the proper term here would be reagent instead of catalyst since it is almost certainly undergoing a transformation from one compound to another. I merely used the term Genepax used to describe the system.)

June 16, 2008 Posted by | hydrogen, water car | 3 Comments