TeamSwift

Lets make it really simple.

Look at the air gap between the + and - post of your battery. That is almost infinate resistance. There is unperceivabley lower power running across that very large resistor (air gap).

Now run a wire from the + post to the - post of your battery. That is almost zero resistance. Feel that heat burning the skin from your fingers and catching on fire? That's high power.

Jay W
505/287 Dakota

looking around a bit I found some interesting thermocouples.

http://www.hi-z.com/websit03.htm

and

http://www.powerchips.gi/ looks promising when it comes out

so if that first one puts out 14W of power it can put out ~ 1 amp at 12V it would take a few of them to run the car totally. at $100 each that doesn't look to practial

however hooking 12 or so of them up and adding an electric water pump would do away with any loss from the water pump or alternator. It might look strange having no pulley on the front of the engine. The electric water pump would also let the engine heat up faster on cold starts and get the thermopile working as fast as possible.

Maybe if there was a cheaper thermocouple around it would be possible to do this mod. I will keep looking around when I get time and maybe something will come of it, but it will probably have to be home made thermocouples. Also it will be hard to do it without adding a lot of weight to the car. I don't think it will be easy to overcome either of these problems but i'm sure someone will figure it out eventually.

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that is very cool. i had never heard of thermoelectricity before.

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www.MetroMPG.com ... www.ForkenSwift.com
... www.EcoModder.com

if we're still brainstorming, i just put these two ideas together...





well, isn't suspension travel wasted energy that's "dumped out" of the car too?

mount the alternator to make use of the front suspension travel. some kind of ratchet setup. (i realize i'm stretching here)

sort of an in-car version of these energy generating speed bumps

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www.MetroMPG.com ... www.ForkenSwift.com
... www.EcoModder.com

Electro-magnetic dampners would be a good start. Although $5000 shocks on a $500 car might seem a little silly.

Jay W
505/287 Dakota

The water pump issue is simple all you do is get a smaller belt and run the pump directly off the crank. there shouldent be a high load so the belt can have some play and still do its job.

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90 Sprint supercharger in a box waiting for warm weather.
85 Fiero GT solo racer custom interior.
81 Audi 4000

If the goal is to increase fuel economy I am not sure there is much to be gained by retrofitting a system to switch off the alternator. Might be worthwhile if you were looking for better acceleration. If you were designing from the ground up with a goal of minimizing the engine size then a system like that might enable you to further reduce the required horse power, but our engine is already in place and I believe that the regulator already switches the alternator off when electrical requirements are satisfied.

but the electrical loads of your running metro are never "satisfied": at a minimum, there's always current draw from the electric fuel pump, the ignition system and the ECU (admittedly small). add in DRLs, and the radio and it's probably significant.

i would be interested in knowing how many amps the g10 pulls at various RPMs with various accessories on and off. from there, we could actually calculate energy savings if we took those loads off the engine.

if i had an induction DC ammeter (think that's what it's called), i'd like to know current draw under various "scenarios":

- engine both at idle and at 3000 rpm (90-100 km/h on my car)
- again, but with DRLs on, both speeds
- add full lights, radio on
- add heater blower on medium
- add wipers
- worst case scenario: all of the above, plus add rear defrost, blower on high

if we knew those amps, we could actually estimate the mpg benefits of removing those loads from the motor. anyone? anyone?? (i know there's guys on here with far more theoretical and practical electrical knowledge than i've got.)

i fully intend to try this when the weather warms up. i already have a deep cycle battery (boat). i already plug the car in regularly (block heater), so i have no aversion to plugging it in in the summer to trickle charge the battery to replace electrical power used in local driving.

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www.MetroMPG.com ... www.ForkenSwift.com
... www.EcoModder.com

I would venture to say the 92 metro convertible I own pulls around 15 to 20 amps with absolutely everything on.

I'm not going to hook up an amp meter (because I don't own one) but consider these accessories. Stereo, Headlights, Running lights, Back up Lights, Emergency Flashers, Coil, Electronic Ignition, Ecu, Brake Lights, Dome Light, Dash/Instrument panel Lights, Dash Warning Lights, Electric Fuel Pump, Electric Door Locks. It is possible to be using all these things but realisticaly unlikely unless your trying to turn everything on.

A few cars in the 90's came with 30 amp alternators. My metro has a 55 amp alternator. When I ran it without the alternator the available power was significantly lower and you could feel the difference in the way the car ran. This is easily fixed by running a magneto. Vertex is one that comes to mind. The distributor makes it's own power for the ignition. IE: no alternator, battery required to run the car. Of course your ECU is no longer needed.

Now on harnessing power for the lights, and other accessories. You could use the faraday principal where you pass a magnet through a coil field of wires to produce electricity. Hook about 6 of these up to each wheel of your suspension and harness the up and down motion of suspension travel. The bumpier the road you drive on the more power you can make! The faraday principal is used in LED flashlights. This is where you shake the flashlight to generate electricity. This type of electric generation is virtually friction free and provides free power. Use capacitors to store the power. This could provide at least 5 amps or so with 24 units properly designed and a real bumpy road.

Another way would be to put magnets on the drive shafts and put a field coil around them and let the magnets spin inside the field coil. No friction such as berrings and belts. Virtually almost free power.

Solar power is another way to generate power.

Capturing wind as you move through the air creates a lot of drag and might take away from fuel milage more than say a traditional alternator setup. Airplanes use this type of setup and it's a Auxilery Power Supply Unit. Abreviation is APU. It has a drop down alternator with a propeller attached to it under the plane. It is for emergency use.

You could also switch all the lights in your car to low power LED lights. This would greatly reduce the power requirements of your vehicle. Not sure how LED headlights would work but I suspect it would not be very good. Bulb technology is advancing fast and there should be brighter bulbs soon.

LED lighting would be a good idea if done correctly. Led's are incredibly bright...the only problem is that they are fairly unidirectional. i think the viewing angle on some of the leds that i have is about 15*. But if you wired several together, and came up with a good reflector system, you could save some serious power there. I think on of my LEDs only consumes 20 miliamps or so.

In regards to the DRLs, woodrufj hit the nail on the head. sorry fordem, you math looks believable but you overlooked something. Power (watts) do go down when you use a larger resistor (in series)...but that power is talking about the power to the lights. the rest of the power gets dissipated in the form of heat through the resistor....which you can also measure in watts (if you do some conversions). If you add a resistor (in series) to a headlight circuit, then the power to the lights will go down (theoretically) the same rate that power dissipation through the resistor goes up. All in all, you just convert energy from brightness (lumens) to heat (degrees).

If there's any physicists out there, correct me if i'm wrong.

i'd be interested to know how much hp is required to spin the alternator when no electrical load is needed. It can't be too terribly much. As Lihtan mentioned, if you use solar panels just to assist the alternator, there could be some benefits there. If you can fulfill the needs of the engine electronics (ecu, fuel injectors, fuel pump, etc) with some solar panels then the battery could always be full allowing the alt. to spin pretty freely. the only time there would be much of a load on the alternator is when you turn on accessories (blower, radio, lights, etc). I wouldn't mind laying solar panels across the entire roof of my car. Hell, you can put them on the hood and it'll ALMOST look like a carbon-fiber hood. But either way i'd leave the alternator belt hooked up and let the internal regulators do their job - which reminds me, you might want some regulators on those solar panels so that your battery doesn't explode.

p.s. I went to http://www.McMaster.com to check out the price and performance of solar panels. The cost/output is pretty steep. assuming you don't have a problem mounting these things to your roof/hood, you could get several flexible solar panels and wire them in parallel to yield 3.6Amps @ 15.4Volts...and here's the kicker...for the low price of only $1,472.00 (plus shipping, handling and tax)! And they say solar energy is free. Ha.


I guess i threw in just a little more than two cents worth, didn't i. well, keep the change.

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Favorite thing to hear at my parties (or in my car), "WHAT?!?!?!?!?! I CAN'T HEAR YOU!!!!!!!!"

OK. First post, but I'll skip the newbie introduction handshaking and put in my two cents here.

You're looking for a way to activate the alternator during deceleration or braking? Why not wire the switch to energize the field to the brake light switch? Then when slowing down with brakes, you get "regenerative braking". The only caveat is during long highway trips, you would want a manual override to energize the field when coasting downhill. I'm sure a voltage gauge of some sort, or your scan tool, would be a must when doing this.

Another idea I wanted to throw in here would be to add a clutch mechanism to the alternator pulley. The clutch could be activated at a certain voltage low point and engage the alternator in a similar manner as the clutch on a typical A/C compressor.

Like BMW's intelligent alternator control?
http://www.greencarcongress.com/2007/01 ... er_in.html

The only downside to that approach is if you've already tailored your driving to minimize use of the brakes (converting gasoline to brake dust is not very efficient), you won't gain much from this approach.

That said, the average person (the majority of the population) who doesn't think much about driving style vs. mpg would benefit from such a setup.

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www.MetroMPG.com ... www.ForkenSwift.com
... www.EcoModder.com

Okay peoples. I think this is worth looking into again. I believe the easiest way to recover mpg from the use of the alternator is to use a switch to turn it off, and install solar panel to charge your battery while the alternator is turned off. I'm not up on the electrical components need to allow the solar panel to charge and automatically turn off the alternator or assist it in charging the battery. Would someone be willing to work with me on making something that works.

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Jon

'91 Geo Metro 3cyl 5 speed 12" wheels 50 + MPG.
'37 Chevy Coupe
'00 VW Passat 4Motion Wagon
'95 GMC Pickup short bed 4x4
'82 28 foot rv, but diesel is too expensive to drive now.

What no takers??? Well it looks like I will just have to work on this task alone...

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Jon

'91 Geo Metro 3cyl 5 speed 12" wheels 50 + MPG.
'37 Chevy Coupe
'00 VW Passat 4Motion Wagon
'95 GMC Pickup short bed 4x4
'82 28 foot rv, but diesel is too expensive to drive now.

The problem is the cost of the panels. An array that will produce, say 5 amps @ 12v (enough to keep the battery from being depleted while you drive) is going to cost hundreds of dollars. Say $300-500.

So it's not impossible, but from a strictly financial angle (if that's your motivation), the payback time is waaaaay off in the future.

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www.MetroMPG.com ... www.ForkenSwift.com
... www.EcoModder.com

Alrighty, so a couple things... Alternators don't typically waste energy by being turned if they don't use it. There is some loss in just turning it and in electrical inefficiencies and it depends on the RPM, but mostly alternators only use the power they are loaded with.
So, a little math
Metro alternator is rated at 55A max. So w/ everything on you could probably pull that much, but not really any more.
Alternators run(I think...) at 14V.
14*55A=770W

That is the max so if you have absolutely everything in the car going at once, it's not going to kill the battery. There are certainly losses here and there(turning a belt and pully system, old wiring so we'll say 80% of actual power goes to generating electricity) and I believe a typical alternator operates at about 80% efficiency. We'll factor that in to bring us to right about about 1.2kW. 1.2kW is 1.6hp. That is with the stereo all the way up, bright lights on, wipers, defroster, fan, everything.
More typically, you'll probably be closer to using half that power so you may gain 1mpg. It's nice, but wiring in a kill circuit won't gain you that much since you're still stuck turning the thing. To really make a difference, you'd need to remove the belt and the weight of the system. Then you'll probably get 2mpg!
It's probably more if you're hypermileing, but for the rest of us, on a car that gets 40mpg, driving techniques are a way better solution. Plus you know you'll get home.

In an A-B-A test at 70 km/h, I measured a 10% increase in MPG by removing the alternator belt (and putting a temporary belt on to drive the water pump) in my '98 Flea.



http://www.metrompg.com/posts/alternator-optional.htm

Though to be fair, at 70 km/h in top gear, alternator load is a significantly larger proportion of total engine power required than at, say 100 km/h, so the savings won't be proportional as speed increases. It'll be most at lightest loads.

Also, according to Wikipedia, a modern alternator is between 50-62% efficient:
http://en.wikipedia.org/wiki/Alternator ... ing_system

I know someone who recently did this in an older Civic CX, and his real world savings was even greater - closer to 20%.

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www.MetroMPG.com ... www.ForkenSwift.com
... www.EcoModder.com

Why not use a mercury switch like found in hood light setups? Position the switch so the momentum of slowing down will activate the alternator. You would have to do some fine tuning to get it just right, but I think I am hitting on something good here!

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Yes, you have some good points. I understand that the best way to improve the mpg, is to remove the alternator and the belts. But I don't want to do this. Most people would like to keep it hooked up also, so if there is an emergency they have a way to keep the car running. But if you are not using the alternator at full then you should see some savings on gas mileage. Also PV solar panels are coming down in price. But if you buy them directly from China they are even cheaper. I happen to have a couple of them, that I'm going to work a way to hook them up to see if I can get something to work out. I was thinking along the line of a switch that would turn off the alternator when you are getting enough current through the solar panels, and then turn the alternator back on when you need more. I like the idea of hooking the switch to the break lights, and the mercury switch trick.

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Jon

'91 Geo Metro 3cyl 5 speed 12" wheels 50 + MPG.
'37 Chevy Coupe
'00 VW Passat 4Motion Wagon
'95 GMC Pickup short bed 4x4
'82 28 foot rv, but diesel is too expensive to drive now.

I put some led flashlights in my car to make a impressive outlook. These lights can be used as my car's back up lights as well.
Isn't it a good idea ?

A magneto on rear disk brakes could eliminate the alternator. That combined with an electric water pump to eliminate the drive belt. Some cooling systems don't need much flow, an electric water pump could cycle on and off as needed. I think some Prius use electric water pumps. Run a trickle charger at night to bring the battery to peak charge. The flywheel of the motor could also have a built in alternator. Eliminating the belts could free up a couple HP, and no squealing

http://auto.howstuffworks.com/electric- ... engine.htm

there are some impressive led headlights on the roads out there, I have been seeing a lot of semi trucks with them; but a starting price per pair is usually around $500 bucks,and you need to have the glass sealed beams to get the best light.
one of the downfalls of these light was that the last time I checked they only made them for the four lamp systems, not two lamp systems....four lamp has separate low/high beam units, where as our single glass sealed beams have both high and low beam combined in one glass unit.

most of them only have one or two large cree leds inside them.....its the patented lens/reflector that makes them focus so well.....and that makes them expensive.

put a wheel on the alt and let it dangle under the car so just the weight of the alt keeps it in contact with the road

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89 1.0 turbo firefly
2"exhaust,no cats/resonator
3 tech 6*gear
3 tech turbo grind cam
3 tech cylinder head/w/port,polish,blend,oversized s/s valves
gti brake swap
89 white gti twincam....need I say more?
92 metro aka ''blue lump of coal''
92 white metro lsi vert
91 blue chevy sprint (gas sipper)