[southpaw]

Hi
I was wondering if anyone has tried using a high volume waterfall pump, in the neighbourhood of 5000 gph to feed a microhydro turbine? Is there any reason why you can't use a submersible pump like this and simply recirculate water in a reservoir, well, lake, pond, etc and create electricity and then use the electricity created to run the waterfall pump continuously. I have been looking around all over the net to see if I can find a similar example to no avail. Anyone have any thoughts on this?

 

[The_Blob]

sorry, that's a 2nd Law of Thermodynamics violation...

 

[MrSfstk8d]

Agree with Bob. That's a perpetual motion machine you're talking about. Google it, and you'll find millions of plans, cheap! Unfortunately, none of them work. Sorry for the bubble bursting. Ah, entropy.

 

[southpaw]

I'm not sure it would be considered a perpetual motion machine since it does require power to run it. The electicity from the turbine would be stored in a bank of batteries and then inverted to AC, from there the electric pump would be run either continuously or as needed to charge the battery bank. I am not sure how this breaks any laws of thermodynamics since I am not really familiar with that. Are you saying the energy created by the turbine/generator would be offset by the electricity used by the electric pump? I am thinking a bank of batteries storing the energy should offset that. What you think?

 

[The_Blob]

succintly put, the electricity generated would not equal that needed to run the pump to displace the amount of water needed to turn the turbine... if it were there would never be an energy crisis because even a one billionth percent excess generated power would eventually become infinite power... this doesn't happen (in our section of the universe anyway).

I am NOT trying to be rude with this explanation, really...

questions are how we learn

that being said... how old are you? (ok, that was NOT meant to be creepy)

:dunno: :gaah: :dunno: :gaah: :dunno: :gaah: :dunno:

 

[southpaw]

I think I was probably already leaning towards the notion it wasn't possible since I was unable to find a working model anywhere, and lets face it, it isn't rocket science, so if it was possible it would be done. I will probably still play with it on a smaller scale when I can go outside and play with some water. Too cold here right now. Possibly if a person could come up with some sort of mechanical pump........gears whirring. I am older than my son and younger than my dad.

 

[NaeKid]

I made something like that years ago, before I learned that I couldn't do what I did and create a perpetual motion machine. My experiment used a car battery, a GM alternator (130amp) and a small 12-volt motor (like a fan-motor).

I ran a belt between the motor and the alternator and tied everything together through the battery. Flip a switch, the battery got the motor going, the motor got the alternator going and the alternator provided power to the battery and the motor.

It ran for a week before I took it apart - the battery still showed about 14-volt at the end of the experiment. I don't know if there would be enough "extra" power to run anything, and, because of the mechanical nature of all the moving parts and the average life-expectancy of a battery, I realize that it will not run "forever", but, while it ran, it was kinda cool.

 

[southpaw]

So theory says, if you would have hooked up 2 batteries in parallel, you could have removed the second battery after they were charged and used it to power something else.

 

[MrSfstk8d]

No, and no. You would have been splitting the electrical potential between the two batteries in NaeKid's example with southpaw's addition of the second battery. There's not a lot of loss in the components he's talking about, especially since they weren't trying to run a whole automotive engine. While some of the charge was gone from the battery, there was still enough left to read in the ~14 VDC range because there's a LOT of mAh stored in a car battery. Think about how long you could run 2 AA hand warmers with a car battery!! It would have eventually lost the battle due to heat loss, friction and aerodynamic resistance.

Same with the gear pump setup for water. Not all (very little, really) of the potential energy in moving water (air for wind turbines) is converted by the turbine. To collect all of the potential energy, you stop the water dead still. If it's still moving, you've only collected X% of the potential energy.

Please please please, don't make me sick the Physics Gestapo on this thread. LOL

 

[NaeKid]

What I believe happened with my little setup was that the alternator was providing enough energy to turn the 12-volt motor and that the battery that was in the system only received a trickle-charge which gave me the reading that I got with my volt-meter.

I might have been able to add a second alternator to the system to run something else, but, it might have caused too much resistance (physical) to the system that the 12-volt motor might not have been able to overcome that resistance and draw too much power out of the battery - over heat and burn-out the windings.

Like I said before, I had it run for about a week. I used heavy-guage starter-wire (4-guage I think) and a standard V-belt between the pullys. There was a fair amount of heat generated by both the alternator and the 12-volt motor ... I am sure that someone smarter than myself would be able to come up with a better system, but, I was only in my late teens when I played with it.

 

[Tirediron]

I have no idea how the battery/motor/alternater experiment lasted a week,with 14 volts left in the system, unless you stumbled on some perfect ratio of speed or some body snuck a batery charger into the mix, when you weren't looking, because everything in your experiment is highly inefficient, it shouldn't have worked. but weird stuff happens all the time. even at 100% efficiency in each component the heat generated by the v belt should have drained off enough energy to drain the battery in a week.

 

[NaeKid]

TiredIron,

The only thing that I can think of is that the alternator put out just a little bit more power than what the 12-volt motor drew leaving enough "residual" power to trickle-charge the battery. I will say that things were quite warm to the touch, don't think that I would have blister'd, but, the belt, the pulleys and the metal-casings of the alternator and 12-volt motor were all toasty.

With the different sizes of pulleys, it was probably geared just right (accidentally) for the alternator to spin faster than the motor in order to produce enough power to do what it did. Knowing what I know now of how the windings in an alternator and DC-motor are setup, I am glad that I didn't reach total melt-down.

 

[The_Blob]

not to rain on your parade, but you drain AMPERAGE from a battery, not voltage, that is why battery chargers have amperage settings... & free-spinning motors with NO LOAD after reaching "contract speed" don't use a whole Hell of a lot of juice, < 100 mA (0.1 amps) average... of course the load in that setup was the alt rating+motor rating+hysteresis losses+friction losses+freewheeling resistance/power consumption which was probably not much more than the alt output rating, but then again you weren't doing any other useful work so...

the avg car battery has anywhere from 60-100 amphours of juice, so:

60/.2(0.1+0.1 for essentially 2 motors)=300 ... 300/24(hrs)=12.5(days) so your week of continuous run is more than believable... but like I said no other USEFUL work was accomplished, you just drained the battery slower

The Lead Acid battery is made up of plates, lead, and lead oxide (various other elements are used to change density, hardness, porosity, etc.) with a 1/3 sulfuric acid and 2/3 water solution. This solution is called electrolyte, which causes a chemical reaction that produce electrons. When you test a battery with a hydrometer, you are measuring the amount of sulfuric acid in the electrolyte. If your reading is low, that means the chemistry that makes electrons is lacking. So where did the sulfur go? It is resting on the battery plates and when you recharge the battery, the sulfur returns to the electrolyte.


sorry... I'm tired & my head hurts... that came out a LOT more snarky than I meant. :ignore:

 

[NaeKid]

Wow!

Thanks for explaining to me why it did what it did. I told a couple other people of my experiment and they all called BS on me. I just shrugged my shoulder and said that I didn't know why it worked, it just did.

:thankyou:

 

[Jimmy24]

I'm thinking you had some REALLY GOOD batteries. 130 amp 12v altenator would require close to 6 hp to charge. Now it will charge at low speed, but amps will be low.

As an altenator charges, voltage will be low if the load (battery in this case) is high. As voltage goes up (battery gets charged) voltage will go up.

In other words high amp, lo voltage. low amps, hi voltage.

I think the batteries were fully charged and just managed to turn the motor, but I don't think any real power was ever made.

Blob's caltulations prove it out.

Worked on automotive electrical for a living for about 6 years when I was young. Learned a bunch. Made all sorts of chargers thru the years.

Now you want a good setup, wood-gasification, 6 hp engine, turning that altenator. WoooHooo...

Jimmy