Hydro-Electric locomotive??

Would it be possible to design a hydroelectric locomotive? And how long would such A locomotive have to be?

In case you're not sure what I've got in mind here:

1.) The electricity to power the locomotive would be generated by a turbine.
2.) The turbine would be turned by water.
3.) There would be a system to recirculate the water.

As long as the water is in steam form, sure.

Wikipedia article on steam-turbine locomotives, both direct-drive and electric drive

Where is the energy coming from to move the water that will drive the turbine?

What I was originally thinking was having a water tender coupled behind the turbine with a sort of "floodgate" (controlled by the engineer) built in. This is why I was thinking it would be necessary to recirculate the water.



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By the way, I'm an American. So if you're British (or perhaps Australian), mentally substitute "driver" for "engineer".

Heard about Perpeteum Mobile?

To the gentleman who asked if I had heard about "Perpeteum Mobile":

No, sir, I have not, at least not in those terms. But I DO have a rudimentary knowledge of Latin and suspect that you are ridiculing me.

The energy derived from hydroelectric power in such an instance as at a dam comes from the conversion of potential energy in the water by virtue of it being at a greater height than it will be after having run through the turbines (to power the electric generators.) The water then empties into a river downstream.

In the design you describe, there would be no energy available to move a train. It would take as much energy to move water back into a storage tank as would be developed moving it out - perhaps more considering losses. In other words, if you did develop such a design and powered a generator with a water-driven turbine there would not even be enough power to refill the tank considering efficiency of the electrical equipment.

-Will Davis

"Perpeteum Mobile" = perpetual motion.

Something would have to initiate the motion, and water isn't known for its abilities to move pertetually by itself, without such outside influences as gravity, pumps, etc. Perpetual motion is like alchemy's Philosopher's Stone or useful nuclear fission...always someone trying to find it, but haven't yet.

Steam still works best: simple as can be. Heat + water + pressure = steam, expansion of steam performs work. Even nuclear reactors are nothing more than big teakettles. Steam turbines have worked since ancient Egypt (however you spell that thing that opened the temple doors) and steam turbine locos have been built to varying degrees of success. Works great for powering ships.

If a perpetual waterfall was indeed possible, my pool might stay algae-free without using that noisy filter pump.

A variation on this would be the "wind generator" locomotive requiring no fuel except the breeze (and of course the JP-4 to power the Jet engine mounted on the flatcar behind the engine for operations in "becalmed" conditions)....

[quote="v8interceptor"](and of course the JP-4 to power the Jet engine mounted on the flatcar behind the engine for operations in "becalmed" conditions)....

only when starting. After a sufficient speed was reached, the wind generator would create enough electricity to keep the locomotive running.

Hmmmmmmmmmmm. Bears considering. I'm glad we got all these ideas out there, gentlemen.

I found some history regarding some oil turbines. Interesting stuff, if you scroll down the page. OIL TURBINE LOCOMOTIVE Not as interesting as a 13 truck shay or elephant powered "bio-loco", but still worth a glance.......

There's no way that a hydroelectric locomotive can go very fast.

Simple physics.

If some water of mass m drops a height h, then it will release gravitational potential energy m*g*h as kinetic energy. If that energy goes into the water's falling, then its fall velocity vw is given by

(1/2)*m*vw^2 = m*g*h

or vw = sqrt(2*g*h)

If the water propel a train with mass M, then the train's resulting velocity, vt is given by

(1/2)*(m+M)*vt^2 = m*g*h

or vt = sqrt(2*m*g*h/(M+m)) = vw*sqrt(m/(M+m))

Now for the absolute best case: doublestack height above the rail, which is 20 ft 2 in / 6147 mm.

The fall speed is 11 m/s or 36 ft/s or 40 km/hr or 25 mph, and the train's resulting speed is naturally much less.

even the best hydro turbines are only 50 % efficent . so you can 1/2 that .

steamal wrote:Would it be possible to design a hydroelectric locomotive?

It seems the answer is "No."