Alternator v. no alternator - 10% gain @ 70 km/h
 

FYI, other GS threads that talk about alternators are:

• Alterpower (shutting off alternator)
  
  
• Does the Civic VX have a unique alternator?
  
  
• Power (accessory type) consumption and FE
  
  
• Solar/plug-in 12V system, alternator optional

Anticipate any difficulties switching belts on the roadside? A-B-A testing is going to be a pain...good luck! Us yocals without instant mpg readouts really, really, REALLY appreciate the effort!

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*sigh* I'd love to, but I have far too many demands on my pocketbook already. I've got other repairs on the car that I should get done before I purchase a MID. I'm having a hard enough time scraping together the money for my exhaust.

Details man! Details! Post something in the daily updates thread.

No, it's away from the hot stuff, and I only need to adjust one bolt on the alternator to get the OEM belt on/off. The home made bypass belt is basically a big rubber band - pretty easy to get on/off. (v.2 has been in service for about 275 km / 170 miles now without self destructing.)

I agree. Driving without FE instrumentation is like drag racing without seeing your 1/4 mile time at the end of the run, or like lapping and not knowing your lap times... until a week or so later when they come in the mail or something.

Back when I was messing with my alternator, I measured the electrical loads of various things (using a shunt on the alternator output). Not a super-exact test, but it should give a ballpark for smaller cars.

I tested at both voltage settings of the alt, where 14.4 is typical alt voltage, and 12.7 is similar to a fully charged battery. The idle current is subtracted out of the other settings.

Idle: 128w @ 14.4v, 89w @ 12.7v
Rev up to 3500 rpm: +35w, (not tested)
Heater fan setting 1: 55w, 38w
Setting 2: 98, 67
Setting 3: 141, 99
Setting 4: 189, 135
Marker lights: 95, 71
Full lights: 240, 179
A/C (heater fan subtracted, but including condenser fan): 163, 114
Defroster: 104, 77
Wipers 1: 48, 38
Wipers 2: 76, 64
Radiator fan: 144, 83

Does that mean that a/c is less of a drag than full blast non-cooled air? Of course you need to add the fan to the a/c, but still, do you get me?

drag
 

The AC will drag the engine directly and not present an electrical load except for any clutch power on the pulley and the blower fan. Nice measurements on the car electrical loads!! How about the car computer, fuel pump and ignition loads??

I have some results.

But first: Randy, great data. Thanks for posting it. What car/engine is it from?

Preliminary results (I'll do a proper write up later with charts & margin of error etc. and post at the top of the thread):

Speed 70 km/h / 43.5 mph

A: alternator belt ON - 71.16 mpg (US) - avg of 3 bi-dir runs (6 one-way runs)

B: alternator belt OFF - 78.08 mpg (US) - avg of 3 bi-dir runs

A: alternator belt ON - 70.2 mpg (US) - avg of 2 bi-dir runs

Notes:

• the last A runs were made after reinstalling the belt and driving for 10 minutes to replace energy taken out of the batt from the B run (simply re-installing the belt and doing the runs would have skewed it as the alternator ran at a higher load recharging things).
• electrical loads, all runs: cruise control, parking lights
• for half of the last A runs: same, plus headlights on (ran out of daylight)

So! That's about double the effect I was guesstimating. I'm expecting a run on deep cycle batteries now...

I wonder if the effect will be different for larger engines, since the alternator is a proportionately smaller part of engine output at a given speed. Discuss. :)

I have a 91 civic hatch std (stock).

If I were to remove the alternator belt, how long would it take to drain an average healthy battery?

How often would I need to reconnect the alternator belt, or charge the batery?

I would be willing to run a test if it weren't to big of a pain.

I guess I could just permanently leave the belt off, and use a plug in charger...assuming the battery stays charged long enough for this mod to be a practical option.

Depends on your battery, your electrical loads, and temperatures (batteries don't like very hot or very cold - performance is relative). Only way to tell is to monitor it.

I drove 50 km with *minimal* electrical loads on a pleasantly warm day and calculated I used about 25% of my battery's capacity. see reply #24:
https://www.gassavers.org/showthread....1807#post11807

See above :)

Also note that just reconnecting the belt to charge your battery erases the benefit of driving with the belt off. You may actually get WORSE mileage if you do that. The only advantage to be gained is if you recharge your battery from an external source (I've been using a solar panel).

Also note: the fastest way to destroy a starting battery is to discharge it deeply & repeatedly. You really need a deep-cycle battery to do this mod properly.

Metro, This solar panel, could it be permanently mounted on the car?

How big is it, $?

where can I get a solar panel good enough so I can remove my alternator?

check out the one with the cigarette lighter option. You could leave it inside the car to constantly charge, right guys? https://www.siliconsolar.com/automoti...y-chargers.php

If you drive a normal amount, it will cost you a lot of money to get enough panels to keep your battery topped up

https://www.siliconsolar.com/shop/cat...ger-p-139.html
"Connect to battery when the car is parked, Simply Built-in LED indicator will light up during charging plugs into cigarette lighter, Suction cups for easy mounting"

• Weight: 1lb
• Dimensions: 12" x 4" x .75"
• 13v @ 200-250mA

$24.95 !!!!!!!!!

*But can it be used while driving, or can any of them? That would allow us

to drive as long as we want, a definite plus!

too bad regular cars don't come with regenarative braking. That way it can charge the battery and run all accesories. it would probably improve 3-5mpg.

[quote=budomove13v @ 200-250mA[/quote]



So this would be really bad, huh?

Looks like less than a 1/4 amp, right?

Can you leave them hooked up while you drive?

If so, how many amps you think you'd need under the most stressful driving to ensure the battery didn't die?

This would be with a deep cycle battery of course.

How much do they cost?

Yup. A 200 mA panel is pretty useless for a car.

Keep in mind, your alternator is probably rated for roughly 55A max output. And it likely runs at around 5-10A in normal driving (light-moderate electrical load).

Meaning, you'd need 5-10 of my 1x3 ft. 1A panels, aimed perfectly at the sun, to provide as much power as the car is taking from the battery while driving. :eek:

You can leave a solar panel connected while you drive.

Deep cycle batteries are a little bit more expensive than starting batteries.

Harbor Freight sells them!

The readings were for my 94 Civic EX. It takes a lot of power to run the thing: 90 watts minimal just idling. All the stuff on, like in the winter, takes more than 700 watts. There's no way a portable panel could keep up with idling, it would be a good load even for a battery charger.

However a full size battery would be enough for maybe an hour, though a starter battery will fall apart after a few times doing this, especially if you try and trickle-charge it. A big deep-cycle battery and a good charger is a better bet.

I am alwas impressed with the markup they put on solor battery maintaners, if you wanted to buy solor panals like you might put on your house, you could exspect to pay around $4-5 a watt if you are buying a number of panels, $24.95 for a quarter watt panal is... $99.80 per watt or 19 times what the panal could cost.
Randy said that he figured 90 watts just to idle the car, correct? and you want to produce more then you use, so round it up to a nice round number like 100 watts to run the car, and charge the battery a little bit from it being cloudy yesterday, of course you don't want to over charge your battery, so you want a charge controler too, and then all the wire, and mounting, and I'm guessing it is going to cost around $500-600 to remove your alternator and replace it with solar, of course the solar panals are going to outlast the rest of your car, so it's a pretty solid investment, but you are most likely going to want to also invest in things like a small alternator that you can kick in at night, and cloudy days, and LED lights all around.

I think the real solution here is find a way to create the turbo-charger alternators.

I've never played with a turbo before, but how much work would it be to gut the internals and hook up an alternator to spin powered by the exhaust gas?

You guys know the device I'm talking about. Maybe it's time to get creative and make our own.

BMW is way ahead of you. They already have a prototype and they said they will start putting it in production cars in 2012

I wouldn't call 2012 way ahead of me. This is why I said we should make our own instead of waiting.

I agree Matt. After seeing one of those I was pretty convinced that it's the closest thing to a "perfect" solution.

The turbos that are probably the most plentiful would be from Dodge 2.2 and 2.5 liter turbo cars. Find a junker and strip the turbo from it. The major difficulty would be getting it mounted to the exhaust manifold. I've been considering it using the manifold and turbo from a Turbo Sprint/Firefly, but it's going to be a while before it happens (like next year...or the next after that).

The added benefit of some mild turbo boost (unless the alternator steals all the energy) could improve highway mpg as well.

Well, I don't think what I have in mind would work as both a turbo AND an alternator.

i don't want to actually turbo my vehicle because it would require lots and lots of money and work. There is still no definate proof that doing so will actually help fuel economy either.

Anyway, this is what I'm talking about:

https://www.greencarcongress.com/2005..._exhaust_.html

Yeah, that Tiger exhaust is what I read as well. And I agree about "no definite proof" regarding forced induction and FE - my statement was simply based on hearsay regarding the Turbo Swift-clones getting better FE at highway speeds than the NA clones.

It's something I'd like to try. The generator would be worth it on its own. If the turbo did help FE that would just be a major bonus.

I wonder about backpressure and how much it would affect FE to generate the equivalent energy of a belt-driven alternator. There's no free lunch!

True, there's energy loss both ways, isn't there?

Agreed... there is energy loss either way. I guess it's just a matter of picking the one with the least amount of energy loss.

Maybe this is something to look into for the future... or I can just wait until 2012.

a friends brother works at a shop that apparently has a "scrap bin" of turbos, I asked him a while back to find me the smallest turbo possible, just the other day he said it was in and that I coudl pick it up, not sure how small it really is, but it might work well for a project like this, he also picked up another turbo with the 5" exuast intake port to use for another turbine engine project, I can't wait to see both of them.

and VW's come with solar panals in them to keep the battery fully charge in shipping, apparently it's "to costly" to send them back to use again, a fully charged battery will last longer.

Me don't care, if you can take out the alternator then me care. Alternator is dead weight.

Well if you're not using it you can take it out. The starter is more of a dead weight than the alternator anyway.

I just want something so I could take out my alternator completly. I don't use the radio. I only use the lights, turn signals, cruise control and very rarely the air conditioner. I've even put LED's to reduce the load on my electrical system.

Then take it out and hook up a solar panel to charge the battery, :p

So there is a solar panel good enough where I could take out the alternator completly???

ok I found out that the belt that is on the alternator also shares the power steering pump and the water pump pulley. So I can't take the alternator out. So what can I do to increase my mpg without pulling out the alternator???

Maybe get a solar panel that will make the car use less my alternator or how does it work?