I suggested this thread, so I guess the least I can do is kick it off.

We keep hearing about people promoting various schemes to supplement or replace gasoline with water.

There are four different ways to use water in a spark-ignition engine. None of them are new. All have been around since I was a kid in the 1950s.

1) Fumigate the intake with water mist. This cools the inlet air (making it denser) and displaces air in the cylinder. In a sense, your engine becomes part gasoline engine and part steam engine, depending on how much water you add. This actually does improve efficiency slightly on some engines in some climates, and has been used occasionally on stationary engines for decades. From what I have seen, the benefit on a motor vehicle will not compensate for the extra weight of water and hardware that you have to carry around. People have been trying these kits since I was a kid and they have never become popular on motor vehicles. That should tell you all you need to know.

2) Dissociate water into hydrogen and oxygen using electricity from the car's charging system and burn gas you produce in the engine. Setting aside for the moment the fact that adding any appreciable amount of hydrogen to the intake will trip up the feedback controlled fuel injection system of a modern car, let's just look at the energy balance. From high school chemistry, we know that water is the lowest energy state of oxygen and hydrogen. To get water to a higher energy state (the pure gases), you have to add electricity. The dissociation reaction is neither endothermic or exothermic (doesn't require or give off heat) so the energy available in the products (the oxygen and hydrogen) is exactly equal to the energy you had to put in to the water to dissociate it.

A gasoline engine has a thermal efficiency of about 25%. That is, we have to put in 4 units of energy (i.e. gasoline) for every unit of work we get out. The other 75% of the energy you pay for is lost as heat, mostly from the exhaust and radiator. Yes, I know that some modern constant-RPM engines, like the one in the Prius, are over 30% efficient, but for the sake of this argument, we'll use 25% efficiency for the average car. Also, I will use Joules as my unit of energy. You may substitute your favorite units, such as Btus.

So, to turn my alternator using my gasoline engine, I have to put in 4 Joules of gasoline to get 1 Joule of electricity back. As discussed above, if I put one Joule of electricity into the water, I will create enough hydrogen/oxygen fuel to create one Joule of fuel energy. I put that Joule of hydrogen/oxygen fuel into my engine to make power, and I will get 0.25 Joules of power back that is available to drive my wheels.

So lets see. Burning gasoline to make power is only 25% efficient. That's bad. Burning gasoline to make electricity to dissociate water and then burning the products in a 25% efficient engine is four times worse! Plus you are carrying around water and hardware.

You may hear the scam artists claim that burning hydrogen and oxygen increases the thermal efficiency of a spark ignition engine. While it is theoretically true that burning hydrogen and oxygen could increase thermal efficiency slightly, compared to burning gasoline, these kits don't make nearly enough gas to measurably affect efficiency. This post is already too long so I won't bore you with the physics of that explanation.

3) Putting water in the gas tank and 'burning' it. You can find videos of people fueling their cars with water and driving away, usually followed by invitations to invest in this amazing new technology.

I am not certain, but I suspect that I know what they are doing.

In the 1800s, people used to make acetylene by reacting calcium carbide with water. This generated a controlled flow of acetylene that could be combusted in air to produce a white light. 'Carbide lanterns' were used by miners, and 'carbide lamps' were used as street lights before the introduction of electric street lights.

We made acetylene this way in high school chemistry lab. CaC2 + 2 H2O => C2H2 + Ca(OH)2.

So, the scam artists rig up their car with a gas carburetor (like a propane or cng kit), throw some hydrated lime into the fuel tank, start the cameras, "gas it up" with the water hose, drive it a few meters, and wait for the suckers to start throwing money at them.

SAFETY
Acetylene at low pressure is moderately dangerous, but not too bad, relative to other gaseous fuels.

EMISSIONS
I expect that you might have one heck of a time passing emissions standards burning acetylene in a reciprocating engine. Greenhouse gas emissions would be similar to gasoline.

COST
Calcium carbide is available on the web for about $80 for a 5 lb can. It is cheaper if you buy it by the ton, but I don't know how much cheaper. For the sake of this discussion, let's say that I can get 15 lb bags for $100 each if I buy a lot of them.

Calcium carbide is 37.5% carbon, so a 15 lb bag gives me 5.6 lbs of carbon. That is about how much carbon there is in a gallon of gasoline, and hence, assuming 100% reaction of my calcium carbonate, this is a cost competitive fuel if gasoline hits $100 a gallon.

If you really like acetylene, you can get acetylene (made from natural gas) somewhat cheaper and easier from the welding supply store, but the price will rise with other fuel costs, so it will never compete with gasoline.

Don't forget, for every 15 lb bag of calcium carbide, you will have to dig about 20 lbs of calcium hydroxide slurry out of your tank, but you can dry it and use it to make drywall, or you can dump it in the ocean to help the ocean absorb the CO2 that you will be making as you burn acetylene in your car.


4) The RIGHT WAY to run a car on water. When GM, Toyota, and Hundai say that they will build cars powered by seawater or wastewater, I expect that they mean that they will use solar or other electrical power to dissociate the water, then they will put the hydrogen in the car, where it will fuel a reciprocating engine, or better, a fuel cell. So technically, the car is not running on seawater, it is running on whatever energy source created the electricity that dissociated the water. If you want to run your car on water, get a photovoltaic panel or a windmill or a water wheel or whatever, and dissociate water at home. Keep the hydrogen and oxygen separate for safety reasons, and compress the hydrogen and use it to fuel a hydrogen car. Then you can sneer at the hybrid drivers because you will have the lowest carbon footprint of all (except maybe for the people with electric cars).

I'm thinking the only way I'm gonna drive on water is to look for one of those '50s amphibians.

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The trouble with doing nothing is not knowing when you're finished.

I think this information may help you out

Have you ever heard of HHO fuel that has got to be the best way to save on gas prices.?
Imagine the savings. It will cost you about $160, or two tanks of gas to install an HHO
conversion kit

Hydrogen Car Kit - Save Money and Improve MPG Massively
Hydrogen car kit empowers your car to run on water and avoid oil as fuel. A vehicle however
will not be able to run on water alone. There needs to be a mixture of gasoline and water to
enable it to run smoothly.

Even the Water Fuel Conversion Kits - How Using Water As Fuel Helps Cut Your Gas Consumption
Recently,there is increased awareness among many drivers of a technology that uses plain
water tosupplement the cars' gasoline consumption. Called a water fuel conversion kit, it is
a simpleadd-on to your current car engine that uses your car battery to carry out an
electrolysis on water to produce Hydroxy gas (HHO). This Hydroxy gas is used to supplement
the burning ofgasoline in the car's engine.

Hydrogen generator kit for car can be better than gasoline or oil additives to raise gas
mileage. When you make or do it on your own, you can save money on gas but will save lots
of dollars on the kit and reproduce the system for other automobiles on your own.

$160 will give me about 5 to 6 fill ups, which is roughly 5 months since I don't drive much.

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Hey, Jad, it looks like we need an easy way to report spam and spammers like sweethe.

lproctor, I'll bet that you are really sweethe and were just looking for an excuse to cuss.

I am okay with keeping it. Without the links, it really isn't spam anymore.

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Man's best friends:

No, sorry... but that's a good idea...

If it were me, everything would be spelled right with proper punctuation and grammar.

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Behemoth at Canada's Wonderland is great!

"you're"

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