Rt in an autococker?

[Jack_Dubious]

Ideas such as that border on the "perpetual motion" ideas. They just dont work. As people have said earlier the Law of Conservation of Energy prevents these ideas. Even if you had 100% efficient fans/generators, there would still be too much energy lost in friction on the rails, air resistance etc. Even with all the mass and momentum of a train....energy is still used to keep it at that speed, even more so with fans causing drag.

To use an old cliche...There is no free lunch.



JDub

[Rick927]

Perhaps air power is not the way to go, if you use a direct drive system from wheels of all cars to generators you can get some of your power there, Add the original idea of solar pannels to tops of cars you get the rest of your power there, a combination of the two might work... the faster you go the more energy you produce, and as we all know once your up to speed it takes less energy to maintain that speed(if its a sunny day) I think it could work. The only thing you would give up is weight/space inside the box car. Your "free lunch" is the sun and the otherwise wasted energy of the rotating wheels. Air drag is now zero, and you would only have to compensate for the added resistance of your drive system which would be minimal compaired to the weight of the train. Just cause no one has done it yet, dosn't mean it can be done. Where would we be if inventors hadn't ignored a law of physics now and then. Remember, helicopters and bumble bee's aren't suposed to fly...but they do.

[Aranarth]

Generators on the wheels. If you add a generator, you make more resistance to turn on the wheels, loading the motors more. Load the motors more, you must draw more power from the battery. You are using copper wiring to connect this thing and to make your motors, which cause power loss. In essence, all you have done is to add a resistor to your circuit. Same with fans. Add fans, add resistance to train movement. Draw more load from your motors, and battery. You can't get nothing from something. Energy is always conserved. You cannot create it, though you can lose it. In this case, every new part you add adds more wiring, which uses more energy.
TANSTAAFL - There Ain't No Such Thing As A Free Lunch
If you want to power your train with solar power, do so. But don't try to add power by adding loads to the solar power cells. You don't come out positive.
-AranarthX

[SlartyBartFast]

Sorry, but the train idea will never fly.(excuse the pun.)

To generate energy without consuming energy is impossible. What is being described is a perpetual motion machine and is impossible to build. It's against every law of physics and engineering.

Think about it this way: whether you use wind or wheel generators to create energy from your moving vehicle, a force at least equal to the energy extracted will be applied to slow the vehicle down. "At least" because any inefficiencies in the harvesting and transformation of the energy will result in higher drag for lower output.

To get one unit of energy from a moving vehicle you have to extract 1.05 units (95% efficient) or greater from the moving vehicle. Wind generators probably get 50% efficiency so you need to remove 2 units of energy for every unit generated. What happens when you remove energy from a moving body? It slows down. To keep it going the same speed you have to put an equal amount back in otherwise you'll just slow down. The "free" train will be consuming at least 10% more energy. In reality it would probably be consuming twice as much. No such thing as free energy.

As as aside: an AC motor with IGBT inverters can theoretically get upto 95%-98% efficieny in propulsion or braking/generating (I work for the worlds largest train manufacturer by the way). So even with the best equipment there are losses to overcome. That's before you factor in wind resistance, rolling resistance, and the thousands of other forces all combining to slow the train down.

[xatle]

run the train in a vacuum tube on a lvl track, use fixed magnets repelling the train from the track creating the illusion of a lighter train, use the same springs for acceleration and deceleration on either end, cover the tube with solar panels charging the batteries at either end that are used to power the motors that give the springs a few twists to make up for lost energy in transit.

hows that for lean power consumption?

[Rick927]

So your saying that you can't recover any of the energy you already have from the moving train cause the generators take more energy away from the train then they produce? and that the energy used to move the extra weight of the solar panels is more the the panels produce? Bummer, I guess we won't be riding on any cool trains any time soon. Oh, well back to paintball!!

[SlartyBartFast]

Cute idea Xatle, but where do the enormous amounts of energy required to create and maintain the vacuum come from?

Not to mention the incredible cost of building the tubes in which the trains would travel. And how would the passengers breath? You've elevated the requirements for the trains into the realms of space capsules.

Rick927, you can still recover energy from the movement of a train. It's just that the only time that you can is when the train is braking. Many if not most modern electric trains will use their motors as generators to brake and put the generated power back into the electric power grid. That way, a train slowing down will power a train that is speeding up or motoring on the same grid.

Actually, even diesel electric locomotives that cannot store the energy use their motors in generation mode to slow the train down. Instead of storing the energy, it is fed to resistor banks that heat up to dissipate the energy. While this is 'wasting' the energy, it gives the train greater braking power and saves the friction brake equipment and wheels from overheating and wearing.

The weight of solar cells would not be the limiting factor in their use. The problem is that there is no solar cell technology that would be capable of providing the power required for a train to operate. I did not mention solar cells in my post as they do not take their power from the motion of the train but from the energy from the Sun.

Nobody called me on it, but I'll confess anyway. I think I broke the rules of DeepBlue. My figures for wind-turbine efficiency were completely bogus. Well the number I quoted is for the efficiency of a ground mounted turbine with respect to the percentage of passing wind energy collected. Unfortunately the efficiency numbers required for our perpetual motion train would be the ration of energy produced to drag created. Still, the idea of getting energy for free is impossible. Any form of energy generation that depends on the motion of the train will result in losses. Even if a 100% efficient generator could be found, the energy generated would only replace the energy taken and not provide any "free" energy to drive the train.

[xatle]

you would only need to pump all th air out of the tube once, after that you seal it with the train inside. the train carries its own air system, passengers get on and off through tubes that extend from the main tube and seal against the side of the train. i think the biggest hurtle would be maintaining the train and the track inside a vacuum. perhaps if the tube had modular sections so that any given section could be isolated from the rest of the tube and pressurized in case of any repair that couldnt be done by a couple guys in space suits. startup costs would be enourmous but once it was rollin it would run almost entirely without any external energy, although i dont have any clue how much trouble the air recycling system of the train would be.

[SlartyBartFast]

This has really strayed from paintball and I probably risk getting stomped by the moderator for being OT, but:

You're forgetting the first principle of engineering. Perfection is impossible.

You can strive for it, take AirGun Designs fine efforts as an example (shameless attempt to be on topic), but you will never achieve it.

It would be impossible to make a tube of the size required to move a train in leak free. You'd always have to be pumping out air.

Add up all the (very expensive) costs and I doubt the energy savings of running in a vacuum would come anywhere near the costs of all the requirements presented. Indeed I'd go out on a limb and wager that the savings wouldn't amount to even a thousandth of the added cost.

[xatle]

dont worry slarty, the mods are pretty good about moveing non deep blue conversation out of deep blue, and deep blue transcends paintball, we could be discussing quantum physics(well, someone besides me could) and they would leave it alone provided it was done inteligently and with evidence.

that being said, i dont see why a tube that large would have so much trouble maintaining a vacuum to the point of being impossible. if your worrying about the extremely small gas particles seeping through the seals such as helium and hydrogen then think of the tube and all of its seals haveing a barrier of heavier, larger particles such as oxygen and nitrogen protecting it.
besides, if it was cheap and easy we would be talking about the train they built last year instead of something they might be able to make a working model of.

well anyway, i dont know how well it could be applied but it sounded good when i was thinking abot it, and i just couldnt let it get shot down by "thats impossible, its too big"

[Snakebite78]

Vacuum

There is absolutely no way to produce a TRUE vacuum, meaning that there is not ONE, not ONE, particle of anything in a given space. Therefore, there would be some friction from air particles, and the idea will not work. As everyone has said, what you are talking about is perpetual motion, which has been tried and tried again. Now, let's think about something else. If some guy on a paintball site has an idea of perpetual motion that "works", then why haven't scientists in the U.S. and other countries figured it out yet.

[Gotenks]

psshhh

the reflex cocker is more complicated than it has to be.

[subbeh]

Originally posted by FutureMagOwner
well i know how to generate that power

you stick a big battery and have it hooked up to one solar panal that is attached to the top of one car and the rest all have windmills. besically the battery powers the train and to get the beginning movement the solar panal charges the battery, then the train as it gets moving makes the wind mills spin because of the extra artifical wind created by the train moving. basically the train powers its self with out any fuels necessary

This would not work as a certain amount of energy would be lost, as nothing is 100% perfect and energy is always wasted in heat, etc. Also, the friction of the road would play a big factor.

[rightsidefight]

listen...instead of debatin all you gotta do in make the train out of rubber(hard in front extremly bouncy in back) and shape it like a bullet.place it in a tube with 2 wheels on top and 2 on bottom.start the train by making the tube totaly level.then using a giant hammer you hit the bouncy part of the train sending it down the tube