

Ask HN: Running a car on water. Plausible or just more bad internet science? - cubicle67

I've got a friend who's pretty smart and a good programmer, who keeps going on about building a car to run on just water. He's convinced it's possible and that other people have done it but that there's a big conspiracy by big oil to keep it covered up.<p>I've sat through all the videos he's shown me, and I've read countless websites and other documents he's supplied, but so far I haven't seen anything like what I'd consider proof.<p>I try and keep an open mind, and I'd love for this to be possible, but all I keep seeing is bad science, appallingly bad science and stuff bordering on outright fraud. The basic premise behind most of these claims is a means of converting water to hydrogen and oxygen, that requires less energy that what's obtainable from burning the hydrogen.<p>So here's my question: Does anyone here know of any evidence that supports this? Do you know anyone who's played with this, or of anyone, anywhere, who has set up a simple closed system to prove it?
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brk
Can you ask your friend to send his tinfoil hat folding instructions? I've
lost mine, and I'm pretty sure his would be superior anyway.

There is a reason you can find no conclusive evidence anywhere in the world
that this is possible even in a lab environment...

~~~
cubicle67
Trouble is, he thinks the videos _are_ conclusive evidence. I can provide
links if anyone's interested (youtube only, no desire to promote these sites)

How do you demonstrate to someone that what they are watching is _not_ proof
when they don't understand what you're talking about? Example - someone takes
a 'fuel cell', _plugs in into mains power_ and exclaims how great it is
because it's producing bubbles. Apparently this is a working example and
therefore conclusive proof. He just does not comprehend when I say that it
demonstrates nothing. Arghhh :/

This raises another question then - how can seemingly intelligent people fall
for such bad science. Why don't people understand the basics of chemistry? Why
on earth can someone who has completed a university level education be so
lacking in the fundamentals of chemistry?

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adamBA
far from possible - it actually takes more energy to pull apart an O-H bond
than you get from burning H2. it has to do with the polarity of the bonds
(oxygen holds on the hydrogen stronger than another hydrogen atom would). I
just looked it up and the heat of combustion of H2 (energy released from
burning) is about 280kJ/mol. while the dissociation of H2O (energy to pull it
apart) is about 920kJ/mol..... so 3-4 times more energy to pull water apart
than released by making it.... now if you strapped a solar panel to the roof
and a wind turbine to the front.... maybe...... ...... nah that still wouldnt
be enough..... complete bs

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cjg
Sounds like bad science too me. The energy put into breaking a hydrogen to
oxygen bond will be the same as the energy release when forming the bond -
which is what happens when hydrogen and oxygen is burnt.

Just think conservation of energy.

Having said that - it might be possible to run a car on water if you had a
fusion reactor that would fit in your car. Pull the heavy hydrogen from the
water and away you go. That technology is still a way off.

~~~
cubicle67
The idea is that by having rods of certain dimensions, and by pulsing the
current at exactly the right frequency, it is possible to break the bonds
using less energy that normally required.

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baguasquirrel
It'd be a violation of the 2nd law of thermodynamics? What sort of energy does
he expect to extract from the water? Is he going to split it back into H2O and
then burn the hydrogen? That just results in the same amount of H2O that you
had to begin with (assuming 100% efficiency). The only way a car could run
purely on water is to get the H to bond with something more chemically
reactive than Oxygen, and that's just not possible since you're just running
on water.

Look at the periodic table. There is just ONE element more electrochemically
negative than Oxygen, and it's Fluorine. So unless he's planning to make a car
that runs on water and Fluorine, it's not possible.

<http://en.wikipedia.org/wiki/Electronegativity>

The one other alternative is fusion, and I'm sorry bud, but it ain't happening
in a car anytime soon.

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RiderOfGiraffes
What does he mean by "Run"?

If he takes electricity, puts it into some magical device containing water,
and unplugs it, and then runs his car on the output, then it all depends on
how much went in and how much came out.

I'll bet more went in than came out.

If he means he puts water into some magical device, and then the car runs on
that, no chance.

There are cars that run on air. They put compressed air into a cylinder, then
drive an engine similar to a steam engine. Then the proponents claim "It runs
on Air!" and in a sense they're right.

Precision required. What actually happens?

Short answer: TANSTAAFL.

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yan
Try to ask him if he really _wants_ it to be true. Everyone has a certain
amount of bias, but if you _want_ something to be true, you'd end up lowering
your threshold of proof to believe something.

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noodle
long story short: no. the process isn't efficient enough for water to actually
successfully fuel anything.

the concept keeps getting rekindled with new breakthroughs, the latest one
being the radio frequency generator that "burns" salt water. its still not
efficient enough to make a car go. not yet, at least.

