http://www.keelynet.com/energy/garrett.htm
http://www.spiritofmaat.com/archive/feb2/carplans_doc.htm
So, from my quick skim, this looks like a simple electrolysis machine, which then combusts the resulting gasses. Anyone with a passing knowledge in chemistry would know that this works in theory. My question is, does this work in practice? In other words, does the resulting explosion generate enough energy to make back the power spent separating the water, with enough to spare to drive a vehicle?
No. It'd be more efficient to just power the car with the electricity used to split the h2o.
That said, it's still a really cool idea :)
This has one advantage; you are able to convert a gas powered car into a "water powered" car, rather than having to start from ground up and build an electric engine. But it is far from efficient.
A friend of mine recently got it into his head that he wants to be an engineer, and he's gotten big on the "alternative engineering" type stuff. He showed me the water car, and I had to explain this part to him:
The more times you convert energy into a different form, the less efficient the process is. This car turns electrical energy into chemical energy (splitting the water into H2 and O2), chemical energy into mechanical and thermal energy (burning/exploding the H2/O2 mixture), then applying the mechanical energy to the wheels and to the alternator to reconvert it back to electrical energy.
It's a silly process really. A Hydrogen powered car would be a great idea if you got the Hydrogen purely from solar power or another truly clean source. As it is right now, you need to use electricity (usually made from fossil fuels) or methane (getting the hydrogen free from the carbon, which releases carbon just like burning fossil fuels).
what's what I thought. Thanks.
So after a time, you will have to put something more than water into the system. Moronic.
Although, methane is a worse greenhouse gas than CO2, so there is a (small) net gain to burning (or converting) methane vs. just venting it to the atmosphere.
Still, there's a lot more gain to be had from simply driving less than from improvements in efficiency. If you just share your ride with one other person, that's a major gain. My wife and I decided to start car pooling when gas started going up, and we ended up saving about USD 200 a month.
Quote from: Kap'n XeviatThe more times you convert energy into a different form, the less efficient the process is. This car turns electrical energy into chemical energy (splitting the water into H2 and O2), chemical energy into mechanical and thermal energy (burning/exploding the H2/O2 mixture), then applying the mechanical energy to the wheels and to the alternator to reconvert it back to electrical energy.
Which makes sense, really, when you think about it. The conversion from one form to another, itself, uses energy. Because of that, energy is "lost" (for practical purposes, anyways) at each conversion.
If it were a fantasy world, however, you cold design a way to magically retain the energy that would otherwise be "lost", and make it considerably more efficient. Of course, as long as you're taking that route, you could do the same thing, only instead of retaining otherwise lost energy, you could replace it (as well as any other energy needed for this to work). Then, at that point, you might as well just throw out the entire idea and say that proper magic can
create the energy required, as well as sustain it.
In short, real-world or fantasy, when it comes to car fuel, just
don't add water ;)
From my understanding, it's not really that energy is used in the conversion (except for the "activation energy to get the reaction started"), but that energy is expended in unusable forms. An explosion in an engine is done to create force, but it also creates electromagnetic radiation (heat/light) that's rather useless to the engine.
This is why fuel cells are a great idea, it converts chemical energy directly into electrical energy; a more efficient conversion (they work by stripping electrons away from a compound and letting them recombine after moving through a converter; you can take the electrons off hydrogen by putting it near a proton permeable membrane, where it instantly will bond with the oxygen in the air and pick up the electrons again. Fun stuff chemistry/physics is.)
Quote from: Kap'n XeviatFrom my understanding, it's not really that energy is used in the conversion (except for the "activation energy to get the reaction started"), but that energy is expended in unusable forms. An explosion in an engine is done to create force, but it also creates electromagnetic radiation (heat/light) that's rather useless to the engine.
Right. I'm aware that energy is never truly "used up" or "lost", only changed, but for all practical purposes, that's what happens to it.
thers a new car coming out where they r getting rid of all the things that make it less aerodynamic, etc. it has 300mpg. still concept car though. they say its comin gout around october 9i think 2008) in Northern california
Quote from: Atlantisthers a new car coming out where they r getting rid of all the things that make it less aerodynamic, etc. it has 300mpg. still concept car though. they say its comin gout around october 9i think 2008) in Northern california
Link?
I'm not saying it's impossible (there's a train than can pull 1 ton and get 100 mpg, so I think a car could do that easily since it isn't pulling a ton).
BMW Hydrogen 7. All that needs to be said. 125 miles on one tank of hydrogen fuel, 325 on regular gas. Also, that car Atlantis is referring to was in PopSci. It should be somewhere on their site.
heres a link Aptera (http://www.aptera.com)
Quote from: Higgs BosonBMW Hydrogen 7. All that needs to be said. 125 miles on one tank of hydrogen fuel, 325 on regular gas. Also, that car Atlantis is referring to was in PopSci. It should be somewhere on their site.
Where do you get your Hydrogen from for that BMW? How much does a tank of fuel cost compared to gas? If that Hydrogen is made through electrolysis, I don't believe you've done anything to help the environment.
er, electrolysis via nuclear energy?
And the question, I don't think, was answered. Using this device, would you have to put in something more than water to run it long-term? Is the engine at least able to produce enough to continue the electrolysis? If the answer to that is yes, efficiency be damned. It runs completely clean, it uses a readily available fuel source which is, to the majority of people in my area, completely free, and the only difficulty would be filling it up on longer trips.
No, the engine goes battery to electrolysis, 2H2/02 mixture explodes in engine to turn pistons, this turns motor and turns tires while also turning alternator. Less power makes it back to the battery than leaves it.
If you were to put a solar panel array on the car, maybe you could keep the battery going in the sun. But you still might as well go completely electric/solar.
The Hydrogen 7 has almost no emissions.
Until you count the emissions from the power plant necessary to manufacture the hydrogen in the first place.
A low- or no-emission vehicle is a good thing, because once you have that you can concentrate your efforts on improving a much smaller number of generating plants. But as long as the generating plants are still emitting, anything that uses power from those plants gets its share of those emissions.
In my humble opinion, the car industry should optimize the hell out of the normal engines/car designs instead of already messing around with alternative engines.
One good example of how this could work is the Loremo (http://en.wikipedia.org/wiki/Loremo), a car that can go for over 800 miles with 20 liters of gas (instead of like 450 miles with 50 liters like some "modern" cars).
I like the idea of highly efficient cars, but I'm not sure how we get to market acceptance. How high does the fuel price have to go before people will switch from their "safe" behemoths to an efficient, lightweight vehicle? I have no idea, but experience with gas price shocks in the past is not encouraging.
Quote from: snakefingUntil you count the emissions from the power plant necessary to manufacture the hydrogen in the first place.
A low- or no-emission vehicle is a good thing, because once you have that you can concentrate your efforts on improving a much smaller number of generating plants. But as long as the generating plants are still emitting, anything that uses power from those plants gets its share of those emissions.
Not to mention, it's better for the environment to have emissions coming from the plant then it is for it to come from the vehicle, all else assumed to be equal.
Quote from: Sdragon1984Not to mention, it's better for the environment to have emissions coming from the plant then it is for it to come from the vehicle, all else assumed to be equal.
That's true for NOx (smog/ozone) and particulates, since plants are usually located away from population centers that would be adversely affected.
For CO2 and SO2, it makes a lot less difference. CO2 affects the whole atmosphere, and acid rain affects large areas regardless of where the plant is.
Then too, all else is not usually equal. It is a lot easier to keep a few power plants well-tuned and maintained than it is for millions of vehicles.
That's definately true. How many people are driving cars that don't meet anything near the emmissions standard, but still use them because it's all they have/they don't care? It's a lot easier to shut down a plant or two that are running too high than thousands of cars.
My question is, why aren't the big oil companies investing in alternate fuels and stuff. They don't have to make them big, just put a foot in the door. Nobody can deny that fossil fuels will eventually run out, so why not be prepared? You know?
Quote from: HaphazzardThat's definately true. How many people are driving cars that don't meet anything near the emmissions standard, but still use them because it's all they have/they don't care? It's a lot easier to shut down a plant or two that are running too high than thousands of cars.
My question is, why aren't the big oil companies investing in alternate fuels and stuff. They don't have to make them big, just put a foot in the door. Nobody can deny that fossil fuels will eventually run out, so why not be prepared? You know?
Because the current generation of executives know that it'll never run out in their lifetimes. Secondly, the majority of the members of OPEC don't have nearly the infrastructure or technological support that research into these things needs. For them, it's best to run the oil to its bitter end, several hundred years from now.
Well, there's increasing evidence that we've reached the worldwide peak of oil production, or are close to it. (For example, the recent run-up in oil prices ought to stimulate more production but it hasn't, suggesting there isn't any spare capacity out there.) If true, this would mean increasing demand facing a smaller supply - and drastic price increases. Sooner or later this will make alternative technologies more attractive.
There is lots of oil out there still, but a lot of it is in oil shales and the like, which won't be economically viable until the price reaches a certain level. So we're not at risk of running out of oil for a while, but the era of relatively cheap oil may already be over.