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ElCamino Man · 08-29-2012, 01:12 PM

Hey guys! Iv had this idea for a way to power my AS when Im off the grid and I wanna see if itll work. Here it goes:

Alternators. They turn, they create power. Simple. Put a fan on the pulley and a fin on the back and youve got a mini wind turbine! Couldnt you mount a few of these on top of the ol AS and get free power? As long as youve got a few batteries to keep some power stored and your not parked in the woods for long, I think its a viable idea!

perryg114 · 08-29-2012, 01:29 PM

You can get small wind turbines for this purpose but you will need a lot of wind to get much power out of one. Take a look on Ebay.

Wind turbines | eBay

Perry

arodriguez60 · 08-29-2012, 01:38 PM

An automobile alternator runs at 1000 to 5000 rpms. you would not get the speed in order to produce power. Also an engine does have a lot of horsepower to turn the alternator when it is producing. Ever notice ythe squeel of a loose belt when you first start a car. It slips when trying to replace the power to start the car.

Bill M. · 08-29-2012, 01:39 PM

I don't.

bredlo · 08-29-2012, 01:48 PM

I've thought about mounting a couple of small turbine fans - plastic blades, maybe a aluminum "eyebrow" protecting it from road rash - and mounting it underneath the trailer. I imagine at highway speeds you'd get a lot of wind channeled under there, without a great deal of lost aerodynamics (which would cancel out the gains).

Could be nice for keeping the trailer batteries topped off, if you didn't have solar, for example.

There was also a discussion recently about a smart kid (well, college age I think) who invented a way to capture the energy created by car shock absorbers. Imagine every time you go over a dip in the road or turn a corner, you'd harness a portion of those forces... as electricity.

ROBERTSUNRUS · 08-29-2012, 01:55 PM

Hi, I have also thought about using an alternator with fan blades attached. My idea was to mount it on the tongue jack facing forward and only charging as I'm driving down the road or possibly on the freeway between locations. Should be easy and cheap to make. People also use tread mill motors for this purpose.

ElCamino Man · 08-29-2012, 02:05 PM

If you set-up the propeller correctly, I could see the alternator spinning at high enough RPMs. The difference between your alternator on your car and the situation im discussing is your car alternator is powering ANYTHING that is electric in your vehicle in addition to charging the battery. So, just taking a guess, over half of your cars alternator is being used in a way other than charging your battery. And you wont have that immediate drop in juice at any time since those batteries arnt being used to start anything. Maybe a slight drop if the fridge kicks on or something but nothing compared to turning over a V8 lol.

ElCamino Man · 08-29-2012, 02:06 PM

Quote:

Originally Posted by ROBERTSUNRUS

Hi, I have also thought about using an alternator with fan blades attached. My idea was to mount it on the tongue jack facing forward and only charging as I'm driving down the road or possibly on the freeway between locations. Should be easy and cheap to make. People also use tread mill motors for this purpose.

This is what I was thinking but then I remembered that the alternator on the TV charges the battery when its hooked up lol. Unless you dont have a 7 prong

ROBERTSUNRUS · 08-29-2012, 05:32 PM

Quote:

Originally Posted by ElCamino Man

This is what I was thinking but then I remembered that the alternator on the TV charges the battery when its hooked up lol. Unless you dont have a 7 prong

Hi, yes this is correct, but how much [or little] are you getting from your tow vehicle [trickle charge] and how much could you get from a separate alternator? [up to 50 amps?] Just guessing; I don't actually know.

perryg114 · 08-29-2012, 06:32 PM

A more direct way of generating power would be to have a 5th wheel hooked to an alternator and that wheel would provide enough torque from road friction to drive the alternator. If you use wind you are creating drag that uses gasoline as well there is no free lunch. Energy(in)=Energy(out) plus entropy.

The wind turbines use a planetary gear box to step up the RPM to something an alternator can use. You can do the same thing with belts and pulleys but those waste a lot of energy in friction.

Perry

ElCamino Man · 08-30-2012, 08:35 AM

Well I got to thinkin bout this then it hit me! Our alternators on cars use a voltage regulator to step up/step down the power when needed. Couldnt the same theory be used if installed on a travel trailer? Turn on more lights, the regulator steps up power. Turn em off for the night, and vise versa.

I could definitly see a flaw almost instantly though... the wind dies down, the fridge kicks on, the A/C is runnin, lights are on.... thatd max out that tiny alternator pretty quick and leave ya in the dark. Even if I installed a couple alternator turbines to match the power, you still gotta have wind...

And to Perry: this idea is more for once you get to the campsite more than driving down the road.

And to Mr. Rob... Robert? Roberts? Robertsun? The cars alternator can charge a completely dead battery in about 10-30 minutes at idle (with no other accessories runnin). So it SHOULD be good enough to charge 2 batteries long before you get to where your goin (I believe)

**DKB_SATX** · 08-30-2012, 09:21 AM

Quote:

Originally Posted by ElCamino Man

Well I got to thinkin bout this then it hit me! Our alternators on cars use a voltage regulator to step up/step down the power when needed. Couldnt the same theory be used if installed on a travel trailer? Turn on more lights, the regulator steps up power. Turn em off for the night, and vise versa.

I could definitly see a flaw almost instantly though... the wind dies down, the fridge kicks on, the A/C is runnin, lights are on.... thatd max out that tiny alternator pretty quick and leave ya in the dark. Even if I installed a couple alternator turbines to match the power, you still gotta have wind...

And to Perry: this idea is more for once you get to the campsite more than driving down the road.

And to Mr. Rob... Robert? Roberts? Robertsun? The cars alternator can charge a completely dead battery in about 10-30 minutes at idle (with no other accessories runnin). So it SHOULD be good enough to charge 2 batteries long before you get to where your goin (I believe)

No, a car's alternator can't charge a completely dead battery in the timeframe you describe, especially not at idle. It'll probably charge it enough to start the car again, but nothing approaching a full charge. Using the engine-driven alternator to charge a dead battery is inefficient, and it's hard on the alternator because that's not what they're designed for. Whenever possible, you're much better off spending the gas money and alternator-replacement money on a decent battery charger instead.

When your alternator is providing current to the engine battery, it's going through a short run of heavy-gauge cable. When the alternator is powering the charge line in the 7-pin connector, it's usually going through a LONG run of light-duty cable and isn't going to be able to supply as much power to the trailer battery as the alternator itself may be able to produce.

perryg114 · 08-30-2012, 01:20 PM

Get you one of those Ebay units and mount it on the roof when you get where you are going. Solar would be a good supplement as well. Wind power requires a steady strong breeze like at the ocean or some areas out west. The little Honda generators would be the way I would go if I needed power for short periods of time and I had access to gasoline. I suppose if you were an electrical engineer and you were looking for something to do, experimenting with this stuff would be fun.

Perry

richinny · 08-30-2012, 01:23 PM

elcamino man

i love crazy :-)

30+ years ago i saw this picture and still think about doing it.

an alternator amplifies electricity unlike a generator that can produce power without it. i think your idea won't produce power without considerable power to turn the alternator. it you want to amplify a lot of power it gets harder to turn. the squealing belt issue mentioned above usually happens when there is a high load on the alternator.

since your proposal and this one both don't produce power when moving i thought i'd post it. if used as sole charge for the trailer it would be regulated without averaging the tow vehicle battery voltage.

jammer did a great post on improving the tv charge line to the trailer here:
http://www.airforums.com/forums/f37/...can-70352.html

ElCamino Man · 08-30-2012, 01:56 PM

I like that driveshaft alternator! Thts nifty! But I dunno if itd be worth the effort lol.

As to the upgrading the trailer wires, that seems like the best way so far. I havent actually gone camping at a location that doesnt have electrical hookups lol. And again, Iv only been camping at 2 locations lol

newroswell · 08-30-2012, 03:04 PM

I like the idea of generating a strong charge while moving. Lots of trucks have 240 to 300 amp heavy duty alternators rated for this kind of charging. Thanks to the need from the ambulance market and crazy loud car stereo market you can get kits for up to 4 high output alternators!

As DKB said, you will need a huge dedicated run of heavy gauge wire from the alternator to a special connection between the vehicle and trailer to get more than a few amps even at highway speeds.

I also like the idea of free power from solar and wind, but I ain't staying too long anywhere the wind is blowing that hard.

Dual Alternator Kit, Triple Alternator Kit, Quad Alternator Kit, GM-Ford-Dodge-Nissan