SpudFiles

sandman wrote:its an electrolysiser that dosent separate the O2 and H2 gas, it makes HHO (Browns gas)

It's no big deal really, instead of collecting the gases in seperate containers, they are collected in a common single container. It's extremely volatile as you might imagine....and it's certainly nothing new.

Ahh, yes I can imagine that oxygen and hydrogen combined are much more powerful than just H2.

Very interesting points about the energy losses. However, if we had a big enough generator to actually run the car, independent of gasoline, the engine would not require all of the gas, all of the time (when the car coasts or decelerates to a stop). The energy loss is still a valid point though.

The generator I built is quite big, compared to ones I've seen elsewhere. I used 27 14ga stainless steel plates. The plates measure 6" by 10". The generator is mounted in a custom made tank constructed from lexan and stainless steel. It runs on a single 12V car battery. The generator has a flow of about 8 cfm. Things I will not disclose are the spacing between the plates, series of stainless steel and the type of electrolyte I used (these things took a lot of experimenting and are shared secrets with someone else already).

I have not tried to run an engine with it because I have yet to build a proper flash arrester.

It doesn't matter how big your generator is. Here will come an example why you cannot run your car on its own generated brown's gas, it also shows why increasing your mileage is unlikely:

Say you use 100 joules of electrical power to electrolyze some water.
You now got some browns gas, and you could say you "stored" the energy in it, you just made the conversion from electrical energy to chemical energy. If your electrolysis cell would be ideal (which is impossible), you would now have 100 joules stored as chemical energy.

When the hydrogen and oxygen burn, the energy is released in the form of thermal energy. Heat causes the gases to expand, and the pressure causes the engine to run. If your engine was ideal, you would now have 100 joules of kinetic energy. However, since alot of heat is lost, and friction exists, your engine is far from ideal.

The engine drives the generator, and again assuming everything is ideal, your generator is able to convert the 100 joules of kinetic energy into 100 joules of electrical energy.

Now the circle is complete. If you would have ideal machines, you would be able to run it forever. But if you want to use the engine for something, you are losing energy: if the engine drives a car, kinetic energy is added to the car's mass, and this energy is lost* by the engine.

This shows you would not be able to have an engine run on his own generated browns gas: you cannot create energy, only convert it, and on top of that, an incredible amount of energy is lost* due to inefficiency.
Every conversion of energy is not 100% efficient and "loses" a certain amount of it. Doing the hydrogen stuff is nothing more then having additional energy conversions.

*Since energy cannot be created or disappear, with lost I mean stuff like thermal energy (heat) coming off. The engine cannot benefit from it anymore and loses it into the environment.

What these "self-powering" hydrogen cars are effectively doing is just running a combustion engine off a battery.

May as well just get an electric car, and recharge it every now and again.
It makes me wonder: What's more expensive, fuel or electricity?

the initial cost of a pure electric car is alot but in the long run it would pay for its self. i read it is about .17 cents a gallon fo electricity.

TurboSuper wrote:What these "self-powering" hydrogen cars are effectively doing is just running a combustion engine off a battery.

May as well just get an electric car, and recharge it every now and again.

This was my conclusion as well, it would be more efficient.

but im fairly confident that electrolyscizers last much longer than batteries

Alright, so I've decided to run some numbers. Not that I don't believe you guys, but I'd like to finalize this with some mathematics.

According to Wikipedia, "regular" gasoline releases 34.8MJ/Litre. Lets assume electricity costs $0.15/kWh. Gasoline around here costs ~$1.50/Litre (CDN).

So 34.8MJ is ~9.67kWh, which would come out to about $1.45.

Ok, so the difference isn't massive. However, electricity varies in many areas, and can easily be between $0.02-$0.07/kWh.

BUT, here's the killer: According to Wikipedia, a modern engine only averages at around 20% efficiency. According to this site:

http://www.engineeringtoolbox.com/elect ... d_655.html

a car-sized electric motor would be >90% efficiency. Mabye it's a different kind of electric motor is used in cars, but I'm sure it is still a long way from 20%.

Therefore, 5 liters of gasoline are needed to produce 34.8MJ of mechanical power in a combustion engine. Assuming your electric car motor is 90% efficient, you would need 38.28MJ, or 10.63 kWh of electricity for the same amount of power. Therefore, you end up paying either $7.50/Litre for 1 litre of gasoline power, or $1.59/Litre for 1 litre of gasoline powr with electricity.

Unfortunately, using hydrogen invokes that woefully inefficient combustion engine. Therefore, assuming that your electrolysis machine is 100% efficient, you will end up spending 5x the amount for the electricity, pretty much negating any gains, since Joule for joule, electricity and gas are quite close.

Lemme know if you guys spot any errors in this, I'm sure there are a few.

@ Sandman: Electrolisys machines need batteries to run. Or they can use gasoline, but then you're using your car's gasoline supply to make a different kind of gas which doesn't make much sense.

sandman wrote:but your alternator always runs so you have electricity that the engine is not using, this should make use of said energy

Nope.

If there is no electrical load on the alternator then it creates zero current and puts very little load on the engine (the alternators shaft spins very easily). If you put an electrical load on the alternator's output then the alternator's shaft is harder to turn. There is no "free" electricity created, the alternator loads the engine down if you are actually using any power from the alternator. If the alternator is actually doing anything then the power output of the engine is reduced. Power to the wheels is reduced, gas mileage is reduced.

There no such thing as a free lunch, especially in engines.

Back to the OP...
The only advantage to any kind of electrolysis system is the same advantage that a hybrid has over a conventional ICE. Basically, you are talking advantage of using a much smaller engine running at near it's maximum power output level (which is also it's greatest efficency) all the time. The excess power generated at a given instant is saved for later use. This allows you to use a much smaller engine. That means you are carrying much less weight. More importantly, you are accelerating much less weight.

The problem with typical car ICEs is that in order for the engine to provide enough power for hard acceleration it has to be much bigger than what is needed for gentle acceleration or to maintain a constant speed. The car has to carry all that excess weight. A 500 HP Mustang probably only needs and engine 1/10th that big for gentle acceration or to maintain 65MPH. But it always has to carry that massive engine for the rare occasion when you want the power.

Hybrids use the gasoline engine, running at peak power output level (and efficiency), to charge the batteries. When power demand by the vehicle is low it draws the energy slowly from the batteries and shuts off the ICE. For brisk acceleration it uses both the batteries and the ICE. Hybrids also recover some energy with regenerative breaking.

So, bottom line, to get any significant increase in efficiency via a hybrid (or HHO) system you need to remove the original engine and throw it in the junk heap. You can't really increase efficieny much if you are still hauling around that big-ass engine, plus the batteries, plus the electric motors (plus the storage tank and compressor for a HHO system).

Once again, there is no free lunch. You are not going to increase the efficience of a standard "lawn mower type" engine by converting it to HHO. Indeed the efficience will almost certainly drop since you don't have the resources or expertise to get everything perfect.

Heck, a well made lawn mower engine is potentially the most efficient ICE there is. Lawn mowers are basically run at full power 100% of the time. That should make it easy to get the greatest efficiency out of'm.

Only problem is lawnmower engines tend to be cheap. Cheap and efficient rarely go together.

Very true. But since you need the batteries as well as the electrolyzer, where is the advantage?

jon_89 wrote:the initial cost of a pure electric car is alot but in the long run it would pay for its self. i read it is about .17 cents a gallon fo electricity.

Never knew electricity came in gallons.

jon_89 wrote:the initial cost of a pure electric car is alot but in the long run it would pay for its self. i read it is about .17 cents a gallon fo electricity.

*Man enters store*
Good afternoon sir, what can I do for you?
-Five gallons of electricity please.
Here you go, that'd be 0.85 cents please.
*Gives money, takes 5 gallon jerrycan full of electricity from the counter.*
-Thanks
Anything else?
-Nope, goodbye.
Have a nice day!

The point is not to get energy out of the water or hydrogen. The burning of the hydrogen is supposed to increase the efficiency of the gasoline that is burning. I help people build these at work almost every day now And have looked in to it my self. I have built several large Electrolysis separators, just not for cars.

so what you are saying is that hydrogen is a catalyst to the combustion of gasoline?

also a car running itself is perpetual motion, and if it was as easy as some are trying to make it seem then there would not be such a debate on the truth of said motion.

not to mention there is no perfect world scenario due to friction, gravity, and many other laws of physics, so in no way would it be possible to have a self-sustaining vehicle.