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Hydrogen Powered Cars
ErrantKbd writes: "CNN's science section features this article about BMW's recent tinkerings with hydrogen-powered cars. It has some interesting information about safety issues, which are understandably a major concern for cars no less than for zeppelins. Hopefully other manufacturers will adopt the same attitude as BMW, so the rest of us can afford these if they should ever emerge on the market." For now these cars have a limited range and one (1) fueling spot, which is fine if you commute to and from the Munich airport. One day, though, it'd be great for the rooftop solar collector to be separating fuel for the next day's commute ...
Toilet cleaner (with HCl) and aluminum foil work well too.
I'd like to see alcohol become a widely used fuel. The corn gets carbons from the air, so when it is burned, the carbons go back to the air. It would solve a big problem with CO2.
If tits were wings it'd be flying around.
Stationary pollution is easier to deal with. Plus, nuclear plants don't contribute to global warming, don't emit ordinary pollutants, and are cheaper than any other technology when all costs are accounted for. And yes, the risk of a nuclear power plant has been socialized. Then again, so has the pollution from a coal plant, or the pollution from producing solar panels.
But rather than argue about it, we should just make sure that each technology has to pay the full cost of its operation. Then we let the free market choose.
Don't piss off The Angry Economist
Let's see...
You're using energy from your electrical system to electrolyze water into hygrogen and oxygen. The electricity replaces, at a minimum, the "heat of formation" energy of the water as it cracks it to its elements.
Then you inject the hydrogen into your intake manifold, where it burns with oxygen from the air, releasing the heat of formation - as heat.
The heat is converted to mechanical power by the engine, which turns the generator to make the hydrogen.
Perpetual motion? Hardly.
A PERFECT heat engine only gets about a third of the energy out of the heat it uses. The other >2/3 goes to heat up a cold place. So you lose AT LEAST 2/3 of your energy each time through the cycle. And while automobile engines are pretty efficient they are optimized for portability, power-to-weight ratio, and a wide operating range. So they don't approach Carnot Cycle efficency all that closely. You need a big stationary power plant for that.
Electric generators are good - you'll probably only lose another 10% there. More for the fan belts.
Your electrolyzer won't be 100% efficient either. And that pump is pure loss.
The hydrogen might do something useful to the mixture. But more likely it will just confuse the engine control computer, which expects to be working with a mixture of gasoline and air, and lower the efficiency of the engine further. (But probably not as far as if you tried it on a pre-computer engine, which doesn't have feedback from an exhaust oxygen sensor to let it adjust the gasoline flow to compensate for the hydrogen.)
I suspect any mileage improvement to be an illusion. But there's one possibility for some improvement from this setup. The bubbler is probably putting some fine water droplets into the intake manifold. Water injection does help an otto-cycle engine, making a non-trivial improvement in both mileage and NOx emissions. The droplets boil and the steam helps transfer the energy into mechanical effort against the piston, while the boiling water cools the burn and reduces combustion of nitrogen.
It's not done in cars because it's an expensive extra complexity, leaves you with TWO consumable liquids to run out of, and tends to rot the metal. Compared to a computer controlled engine without water injection it's not enough of an improvement in performance to justify the costs.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
March 17, 2005
It seems that the long touted "clean fuel" of the 21 Century had some unfortunate and unexpected consequences today when the massive amounts of H2O released into the atmosphere finally caused the earth to sink (The process of continents passing below the rising surface of the ocean) due to the exhaust created by urban commuters.
"We were really caught off-guard on this one," says John Shepley, an engineer at the BMW Space Station, one of the three man made structures still in existence. "Everyone knows that the coasts have been crawling closer and closer for years. The granola eater types really started complaining when California went under, but we figured all that liberal spouting was just hyperbole. I guess we were wrong."
The engineers have been working for some time on further innovations that may make the world inhabitable once again. "Yeah. We can make a machine that uses electrolosis to turn water back into its component H2 and O2 molecules, but the only design we could come up with used fossil fuels. We figured, no, we'll stay away from that. The use of fossil fuels can get you into all sorts of trouble."
I think you can figure out why.
NO CARRIER
Hydrogen burns quickly and more importantly goes UP as it burns, away from the veichle.
Gasolene on the other hand burns slowly (in liquid form), flows everywhere, and sticks to everything it touches.
Now which one, do you think, would produce more 'gruesome' accidents?
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Soma: because a gramme is better than a damn.
The amount of electricity required to electrolize water isn't that much, and isn't required all at once.
You could have a giant field of solar panels slowly generating electricity and breaking tanks of water into O2 and H2 with little supervision needed.
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Soma: because a gramme is better than a damn.
The Hindenburg dident blow up because itw as full of hydrogen, it blew up because it was coated in the same stuff the Solid rocket boosters on the Space shuttle use for fuel, or at least something verry similar.
Hydrogen fuel advocates are assuming, perhaps correctly, that once economies of scale are applied to hydrogen that more long-term and large-scale production methods will become practical and economical. But it hasn't happened yet.
Brackets contain world's first nanosig, highly magnified:[.]