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Discussion Starter #1
As much fraud is associated with water-fueled cars, there really is a working concept that involves plugging the car into an electrical socket to electrolyze the water into oxyhydrogen for use as a legitimate fuel. So far, no one who has attempted to capitalize on oxyhydrogen combustion engines has tried to do that. Just a bunch of quack home-made engineers trying to sell you a DVD+ do-it-yourself-kit that's doomed to fail.

Oxyhydrogen goes by many names. It's also known as HHO, or Brown's gas. It's actually a mixture of 2:1 mole ratio of H2 and O2 gas. It is made by applying a DC voltage to water (hydrolysis) to separate the two elements.

In the 90's, there was a man by the name of Stanley Meyer who fooled the world of fringe science into thinking that water alone can be used as a fuel. What any chemist, physicist, or smarter-than-average high schooler can tell you is that it takes MORE energy to electrolyze water than the energy you get out of it by igniting the oxyhydrogen product as a fuel, meaning a car cannot use water as a stand-alone fuel. It needs to be hydrolyzed first.

There are some useful and interesting facts about oxyhydrogen combustion, though. Stanely Meyers wasn't lying about the following:
1) clean burning fuel. The only by-product is pure H2O water. In some cases extra hydrogen gas is added to prevent oxidization of the metal it contacts, which means extra H2 might escape the exhaust. But H2 naturally breaks down in the environment, and is not considered a greenhouse gas.
2) cheaper than shit, quite literally. It's water, after all. The only thing Meyer forgot to mention is the need for external power to hydrolyse the water. With cheap power-grid energy, this is still pretty cheap.
3) POWER. Electric cars do not perform as well as the classical gasoline-combustion engines. However, oxyhydrogen has been tested laboratories to burn as hot as 2000-2800 degrees C. That's some powerful stuff. Racecars can be powered on it, provided they have enough room to store the oxyhydrogen gas.
4) Compression - this gas can be compressed into a pressurized tank. This means that it will be cold as a witch's tit when injected into the engine. No need for Nitrogen hits to cool the fuel line. Compression is one of the main advantages of CNG fuel, which is made of fossil fuels and doesn't burn as clean.
5) Accessibility. It's hard to keep a gas station open when the world is running on plug-in cars. It takes at least a few hours to charge a battery, and nobody's going to wait that long. With oxyhydrogen, fuel stations can readily fill your tanks for you on the run, just like they did with gasoline but now in compressed gaseous form rather than liquid.

Then there's the wall receptacle. Most electric car concepts involve plugging your car into a standard 120VAC outlet (or a 240VAC socket if you keep your washing machine in your garage, lol). These cars usually charge the LI-ion battery equipped in your fancy pantsy californian I-like-to-smell-my-own-organic-farts car.

But Li-ion batteries are expensive, which raises the MSRP of any one of these cars. It also makes replacing the LI-ion battery expensive, which you will undoubtedly need to do 5 or 10 years later. With advances in super-capacitors, LI-ion might eventually leave the world of automobiles.

A sedan is just big enough to be equipped with a hydrolyzing apparatus that can be powered from your 120VAC wall receptacle. Also, a waterline into a reservoir will be needed. As your car refills with water, the electrical power from your home can hydrolyze it into oxyhydrogen gas.

As an alternative, owners of such a car can have a fuel station right in their garage. The garage apparatus can hydrolyze water into oxyhydrogen while your car is gone, and can quickly refill your compressed tanks before you leave in the morning.

-Taylor Holmes
The humble drunken engineer, mathematician, and penyless entrepreneur.
 

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Discussion Starter #3
The energy density of gasoline is about 5.5 times the energy density of HHO gas.

When you think about it, it's really not that bad at all, considering all the other advantages.
 

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I guess I don't understand what your point is. It sounded like you are pointing out the benefits of HHO gas as a fuel and now you are pointing the benefits of gasoline over HHO. It was the US Government funding of $1.2billion for education of our middle and high school students a few years ago about a hydrogen economy that I learned the inefficiencies of using H2 to power our cars. Quite ironic considering the education tools and training I was given was supposed to do the opposite.
 

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Discussion Starter #5
I'm not saying that H2 is more powerful than gasoline. Very few fuels are, and even fewer of them can be used in an automobile. And almost none of these are clean-burning.

I'm just saying it's a possible alternative when hybridized on a plug-in car.

For example, a Li-ion battery has an energy density of about 0.46 - 2.54 MJ/kg. Gasoline has an energy density of about 46.4 MJ/kg, yet somehow we've been led to think that Li-ion batteries are going to save us. Gasoline has literally a hundred times the energy per kilogram. It has only around 5.5 times the energy per kilogram of HHO gas.

Is it really that far of a stretch?
 

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I'm not saying that H2 is more powerful than gasoline. Very few fuels are, and even fewer of them can be used in an automobile. And almost none of these are clean-burning.

I'm just saying it's a possible alternative when hybridized on a plug-in car.

For example, a Li-ion battery has an energy density of about 0.46 - 2.54 MJ/kg. Gasoline has an energy density of about 46.4 MJ/kg, yet somehow we've been led to think that Li-ion batteries are going to save us. Gasoline has literally a hundred times the energy per kilogram. It has only around 5.5 times the energy per kilogram of HHO gas.

Is it really that far of a stretch?
Taking your own numbers, gasoline has 18 times the energy density than Li-Ion. If you take the higher number instead of the lower number. That combined with the fact an ICE can reach 30% eff (a high number), and an EV 90% eff, the difference comes to 18/3 = 6. So gasoline in an ICE is effectively 6 times more energy dense than Li-Ion. Now consider that.

By the way, a mixture of H2 en O2 in a tank is prety exiting to cary around.
 

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Discussion Starter #7
You may be right, I didn't factor in efficiency. That high end number was for Li-ion nano wire batteries... I'm not sure if that's what's being used in EVs or not.

I bet carrying around H2 would be scary as all hell. It's like carrying around a miniature Hindenberg story waiting to happen. The dangers of H2 are one of the reasons it's not being used in cars. When added to the right mixture of oxygen, it's a bomb waiting to happen.
 

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Hi Hell

H2 is a scary fuel because of its wide explosive limits and the ability of hydrogen to leak (caused by low molecular size),

A mixture of oxygen and hydrogen is beyond scary! - all it needs is a tiny tiny static spark and its a bomb

The trouble with H2 as a fuel is not its energy/kg - which is good
its its density - energy/litre - which is terrible
0.089gm/L ----- 89 gms/m3
11 cubic meters to get 1 kg!
11 m3 of petrol is about 7,700Kg
- so you end up compressing it to a sensible density -
unfortunately the energy taken to compress it amounts to a large percentage of the available chemical energy

Compressing a hydrogen - oxygen mixture is beyond bad - a tiny spark will ignite it at room temp and pressure
if you increase the pressure you reduce the energy required to start the bang!
 

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Aside from here I've never even heard of anyone suggesting storing compressed H2 and O2 mixed together. I thought the whole point was you can carry around your H2 and mix it with the oxy already in air, so you're only carrying some of your fuel, scramjet style.

In my mind H2 is part of the ideal solution for energy independence, used to store power from solar panels for night/winter power via fuel cell. Some guys in MA did this years ago and if it works there, it'll work anywhere, the only issue has been the price.

Home size fuel cells are supposed to hit $8K soon, which really makes it a practical possibility, and there was a story on here recently that even that price could drop by 75% in the next 5-10 years.
 

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Aside from here I've never even heard of anyone suggesting storing compressed H2 and O2 mixed together. I thought the whole point was you can carry around your H2 and mix it with the oxy already in air, so you're only carrying some of your fuel, scramjet style.

In my mind H2 is part of the ideal solution for energy independence, used to store power from solar panels for night/winter power via fuel cell. Some guys in MA did this years ago and if it works there, it'll work anywhere, the only issue has been the price.

Home size fuel cells are supposed to hit $8K soon, which really makes it a practical possibility, and there was a story on here recently that even that price could drop by 75% in the next 5-10 years.
Until you realize the process is less than 5% efficient, and you really like paying 100 times more for electricity.
 

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Discussion Starter #12
The efficiency of electrolysis isn't that big of a deal, since it can be made in your garage from power-grid electricity plugged into your car.

It's the efficiency of the H2 and O2 ICE engine that I really don't know about.
 

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I think there are two more points that need to be hit on.

First of all HHO is even less energy dense than straight Hydrogen because you are carrying the oxygen supply around with you in addition to the hydrogen.

Second and most importantly. When water is separated to make hydrogen, it is always kept separate from the oxygen. By keeping the mixture together, as is too often done in HHO scams, you have the perfect concoction in the perfect ratios to make the perfect rolling bomb.:D

Unlike traditional hydrogen gas tanks, the addition of a simple spark would do nothing, because there is no oxygen in the holding tank to oxidize in a combustion situation. In an HHO tank the hydrogen and oxygen are still together, all you need is a spark and BOOOOOOOM!!!!!:eek:
 

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So what's the hit on efficiency for each part, electrolysis and the fuel cell?
Assuming you can match the efficiency of professional equipment somehow at a fraction of the cost.

Here is a Hydrogen electrolyzer for $10,500.00
Ignoring for a moment the need for pure water.
Ignoring for a moment the energy used to compress it.

It produces up to 36 L of Hydrogen per hour using 300 vA
36 L uncompressed = ~108 Wh of chemical energy stored as Hydrogen.
I don't have the AC power factor of the device but we know it is less than 300 wh in 1 hour, which means ~36% efficiency.

~36% efficiency to get the hydrogen ... into a ~30% efficient ICE = ~10.8% net efficiency combined ... ignoring several other sources of loss.

Compared to the net % efficiency of just using the same electrical energy in a BEV ... I think the BEV is obvious.

- - - - - - -

The way I see it ... the ICE is still the killer ... even if you found a inexpensive way to do electrolysis at ~99% efficiency ... ( call it magic ) ... the ~30% efficiency of the ICE still puts it at less efficient than a BEV using the same electricity.

No fuel cell is as efficient as a battery ... even if you had a magical ~99% efficient way to produce hydrogen with electricity.
 

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I'm not saying that H2 is more powerful than gasoline. Very few fuels are, and even fewer of them can be used in an automobile. And almost none of these are clean-burning.

I'm just saying it's a possible alternative when hybridized on a plug-in car.

For example, a Li-ion battery has an energy density of about 0.46 - 2.54 MJ/kg. Gasoline has an energy density of about 46.4 MJ/kg, yet somehow we've been led to think that Li-ion batteries are going to save us. Gasoline has literally a hundred times the energy per kilogram. It has only around 5.5 times the energy per kilogram of HHO gas.

Is it really that far of a stretch?

Although gasoline has almost 20 times the energy density of lithium batteries, you have to stop and think; The motor that burns the gasoline is only 26% efficient, while the motor that runs on batteries is 75% to 95% efficient.

Gasoline's advantage slowly fades away...
 

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Hi Hell

The energy/mass is not the problem with hydrogen as a fuel
Its the energy/liter!

11 cubic meters of hydrogen = 1kg = 9 Mj = the equivalent of 3Kg of lithium cells

Which will fit your car better 300Kg of cells or 1000m3 of Zeppelin! - thats a cube tem meters on a side

You can compress it - but that takes energy AND strong tanks
 

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The part that makes the whole electrolyser thing interesting is the fact that it can be an on board item, making the hydrogen/oxygen mix as you drive. There is no pressurised tank to explode and with a little intelligent for though the risk of an electrolyser explosion is minimised by using a water trap close to the point of entry to the ICE stopping the dreaded flash back. No spark arresters or conventional flash back arresters will work with this stuff because it's at the perfect burn mix and the flame front is so fast. It's the rapid flame front that makes this fuel so desirable in an ICE because it can burn all the fuel present in the combustion chamber in one hit at the point of peak power gain.
The other positives regarding this fuel being combined with the normal fuel is the reduction in peak combustion temp thus reducing NOX production and the natural cooling ability because the hydrogen/oxygen mix when burnt reverts back to water, or in this case steam, and carries a lot of the heat out the exhaust. This steam also has another function, it's the bit that absorbs the peak combustion temp that causes all the detonation problems and by doing so becomes super heated steam. This super heated steam releases it's energy as the peak pressure drops, just after the piston passes over top dead centre thereby increasing the torque component of the power stroke.
All this from water, but there's a catch (isn't there always) The amount of energy required to separate the hydrogen from the oxygen is quite large, generally considered more than the energy produced, this one is a very grey area because often the ICE isn't optimised to fully use the benefits of burning this combined gas so a lot of the gain is lost through inefficiency. An example, if the waste product from burning the gas also removes heat from the combustion process then energy is being wasted providing the level of internal cooling that a standard ICE requires. So if the original mechanical water pump is made ineffective by removing the impellor and an on demand temp controlled electric pump is substituted some HP is gained. Next, the alternator that generates the energy for the whole system to operate is also very inefficient but the standard battery would go flat without it.
So, what if a pack of LiFeP04 batteries were fitted to provide the energy, this could be charged over night on cheap power and used to power the vehicle and the electrolyser while driving. The alternator could be program controlled to charge at it's peak output during decel but zero output any other time. This would give a form of regen braking although small and recoup some of the waste energy, as the alternator would only be under load for a short period it could deliver it's peak output without overheating. A conversion to a higher output alternator would be another possible consideration.
The next problem is the engine management system, it's designed to control the emissions of a standard ICE but if NOX is eliminated then EGR is no longer required, ignition timing delay under high load isn't required as detonation has been controlled and lean fuel burn can be now utilised as combustion temp has been controlled so the oxygen sensor needs to be read in a different context. Instead of 14.7:1 fuel ratio up to 16.5:1 is now achievable with no engine damage and no increase in emissions.

All this is very achievable but it would require a vehicle by vehicle set up and computer reprogram on a dyno to achieve so not something a vehicle manufacturer is likely to get involved with, mass production of thousands of vehicle all the same it the name of the game there but the individual converter has the time on their hands to do this sort of stuff. Just a few things to think about.
Another thing to think about is the energy to split water to hydrogen and oxygen doesn't all need to be electrical, in fact if the temp is high enough water will spit by itself so a combination of heat and electrical energy will reduce the amount of electrical energy required. some things to think about.

T1 Terry
 

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O.K. two problems with the previous post, which is too long to quote, is this.

First of all yes, you are correct that water will spontaneously disassociate at high temperatures. Unfortunately the temperature we are talking about is 2500 degrees C.:eek: Personally I don't want to play with heat high enough to melt metal.

Second of all, and most importantly, hydrogen is an energy carrier, not an energy source. It should not be referred to as a fuel any more than your lithium battery pack should be referred to as such.

Another interesting note is this, thanks to that pesky little law of conservation of energy, I am afraid all forms of energy take more energy to produce than you will ever get in return.

As far as using a battery pack to make hydrogen as you go, think of this.

since 1 mole of H2 weighs 2 grams, 1 gallon of gasoline is therefore equivalent to 500 moles of H2;

thus, the electric power required to electrolyze the hydrogen equivalent to 1 gallon of gasoline is equal to (500 moles) × (0.06587 kWh/mole) = 32.935 kWh, and the approximate cost of that power = (32.935 kWh) (@ 13.5¢/kWh) = $4.45 per 'gallon-equivalent' (or "gge"), using our power bill's cost / kWh! [This is actually a fairly realistic computation, since commercial and industrial customers typically pay at least what residential users do for day-rate power. It should be noted, however, that night-rate power is now typically 45 to 53% of the day-rate price – which would proportionally but dissimilarly affect the electrolysis-based cost-per-gallon equivalence computations below, case-by-case!]
 
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