Idea for using Solar Power......
 

Ok im not no electrician so I need everyone's input here.

This is my simple idea, on my 93 Civic the alternator belt is seperate this makes it easy to remove for improved gas mileage (it's still on). Anyways couldn't you just get a few solar panals add 2 extra batteries and let the solar panals keep the batteries charged. So I could drive without the alternator all day long?

How much power would the panals have to produce to do that. My commute to work is just 15 miles and then the car would sit in the sun for 9 hours then drive 15 miles home. It would just be Solar panal -> power inverter -> batteries correct?

I don't even know how much extra MPG i can get with taking off the battery but I think I am in the right direction. And how big of a panal would you need to keep 1 battery running off of the sun without draining it?

The only thing that sucks right now is my wife uses the car as a Daily Driver, but this is just an idea.

Lets here your input.

I think people have discussed this before and it turns out you pretty much can't make enough power with a reasonable number of panels. You might want to search and find the details. solar and alternator would be good search terms.

It works in theory, but I read the post on MetroMPG.com that kind of bunks the savings: https://www.metrompg.com/posts/alternator-optional.htm

"Unless you happen to have a source of cheap or free batteries, you need to do the math before jumping on this mod as a way to save money."

I think some people HAVE done this, but Im not sure if they are using solare panels to recharge the batteries. I know someone used deep-cycle batteries and was able to make complete commutes where the battery was able to power the WHOLE trip. Im not sure how log the trip was but I would love to replace my regualr battery with a deep-cycle one.

This is interesting timing as I was JUST thinking of a similar project where I use a solar panel to lessen the load on the alternater. This is a very SAFE way that removes any worries about running out of power. Im not sure how much FE you would gain, but the alternater would have to work a tinsy bit less. Worth the effort- probably not because the instantaneous draw is prob way too small for the alternater to really appreciate.

However, if you disconnected the alternator then it seems viable IFF you used deep-cycle batteries and maybe a couple of panels.

I was actually trying to see if I could reduce electric bill at home by attaching solar panels to a battery with an DC-AC invertor to power smaller devices. It would take a while to pay off, but would be interesting. I found a Xantrex battery on Amazon (although I could prob just buy regular cra battery for cheaper) and a 15 Watt solar panel to charge the battery. Here are links. BTW the solar panel's size might be perfect for mounting on your rear trunk, so it wont cause any aero drag. You MAY also be able to fit one in your rear dash. Would do you think??? These MIGHT be enough to trickle charge deep-cycles if you dont have long commute and are easy on lights,radio ect
Battery link- this is CONVENIENT all in one battery kit- can prob get more power for less money if you just buy plain car battery.
https://www.amazon.com/Xantrex-XPower...375420&sr=8-16

Link for Solar Panel:
https://www.amazon.com/exec/obidos/tg...X0DER&v=glance

A 15 watt panel wouldn't save too much. You could power one CFL light. :D For the price of equipment I don't think panels and deep cycle batteries could easily offset the savings from not running an alternator. As that MetroMPG article showed, they needed something over 300 watts for regular usage, you would need a big van for the surface area for that much solar paneling I imagine. But if you're doing it for the fun of raising fuel economy or decreasing gas usage (while increasing silicon usage), it would be a fun project.

korax123 -

I think it's worth trying if :

- You have another use for the solar panels and batteries if it doesn't work.

- You keep a special "emergency battery" thingy that you can plug into the cigarette lighter to start the car. That way, a dead battery won't keep you from getting home. SNEAKY IDEA : Assume your battery is always dead. Plug the charger-battery into the wall at work every day and when you get home. Use it as your "mobile starter energy source".

- You're commute "fits" in terms of amount of energy lost in the battery and the time it takes to recharge the battery.

- You don't worry about the "return on investment".

I have been thinking along similar lines, because my car "just sits there" all day too. My problem is, 35+ miles one way is "A Commute Too Far" for my battery to be rechargeable.

CarloSW2

Just an idea guys; I haven't thought it through. Has anyone tried a A/C clutch on an alternator?

Pros: It seems like it would reduce ALMOST as much power loss as removing the alternator. You could re-enable it easily in case you had an emergency, such as staying at work late and driving home with headlights, or running the battery too low for comfort. It may be hard to remove the alternator if you have a serpentine belt.

Cons: Still some parasitic loss in the clutch bearin. The car gains weight instead of shedding it.

No need for that. All you need to turn the alternator into a fancy looking pulley with almost no loss is a relay, a switch and some wiring. The alternator only puts a load on when exiter voltage is present, in the little 2 wire plug in the wiring harness. Cut that voltage off and the alternator won't charge, and all you need for that is a relay that is normally closed, and opens when energised. Then, just flip the switch when you want the alternator either on or off.

This is what SVOboy (i think did) He has a switch to turn his alternator off and on.

Why won't automakers just make the alternators like that and have the computer measure the voltage of the battery and when it gets to a certain voltage kick the alternator back on.

Wouldn't this save fuel and just put a deepcycle battery in the car to take all the recharging.

elec cars go around 30-40 miles round trip. I think they need 80-200 square feet of solar panels to charge for a few hours. the battery is only for starting the car, you can disconnect it while running and the alt will keep it running by producing 14 volts I helped a friend who had a Geo storm, the alt was bad, i charged it for 10mins with my truck, she drove for around 5miles until it ran out/stalled, after 6-7 charges she made it home ;) also if you run on just batteries the computer might act goofy , not getting the normal 12v or 5v ref signal, not making a good spark or have a low fuel flow. On newer cars it will set the airbag light on for low voltage detected and may turn on all the lights on in the dash, set a bunch of codes, and if elec throttle body, you will be in idle mode only-won't be able to push the gas to go.
my experiment would be to start the car, remove battery, run to work, use second battery stored at work to start the car again, return home. but... you might blow the battery up from any spark from connecting / disconnecting and/or the car will have to relearn the driving strategy 2xs a day that might lead to bad mpg. finally if it stalls your out of luck ;(

The alternator on our Odyssey does "upshift" and "downshift" depending on load. I don't think it ever totally kicks off, but it might...

That is basicly how the built in voltage regulator works, at least the alternator on a honda, and alot of other cars, will not put out anything without a feild voltage, cut that power, and it's just a spining mass, and that voltage varries depending on the battery voltage, and that varries depending on electrical draw, if you do a search you will find a page that I started where I put an amp meter on my battery, and turned on differnt parts of the car, the computer and coil my civic draws a minum of 80 watts, solar is $5 per watt, and on average you might get 4 hours of solar per day, so that $5 per watt will get you 4 watt hours per day, average person drives 20 miles per day at something like 25mph average, so lets just round that up to an hour of driving per day, so $100 worth of solar to alow you to drive one hour per day, just for the cost of solar and that might be half, so $200 so you can drive 20 miles a day without lights, or a vent fan or radio.

GM started doing this in about 2005. It's one of the things they did to try and boost mileage on the trucks and SUVs, along with installing electric fans on them from the factory. The computer monitors and controls alternator output vs battery load. And, usually when GM does something small like this that puts something under the control of the computer on one vehicle, they do it to all of them, to make them more complicated to work on. I mean, who's going to want to replace their own alternator when they know it's computer controlled?

hey! thats my idea! but i want to try this out with 2 baterys and my roof covered in solar panals

Telco knows the story but Honda has been doing the same thing at least since 1992. The ECU of my 92 Civic VX shuts the alternator off when it's not needed. The alternator is only shut off at low speed (50 mph or less) and the headlights and/or AC must be off at all times. How do I know this is true? The helm manual for the Civic tells you and I know because I installed an aftermarket voltmeter under the dash by the fuse box to keep track of it. The voltmeter drops to 12V when the alternator shuts off and jumps back up to 14 V when the alternator is engaged again. The alternator is running constantly at high speed - 70 mph because the distributor needs the voltage to spark the cylinders. You can't run on battery power too long without draining the battery. I know, boy do I know this!

Solar panels? Great concept but not enough power density. A fuel cell or other high density power source would do it - Hey! how about a belt driven alternator. (I know I'm being a smart a**)

On a carburettor car, you can drive a long long way without alternator (e.g. I drove 60 miles once, with a few starts, in a carb car). The ECU in my car actually gets hot to the touch, so this is a waste of power if running without an alternator.

How about converting some of that waste energy in the exhaust system into electricity? That could be done with thermopiles or a Sterling engine.

Speaking of waste heat, I looked at using it to power steam-driven air conditioning, but the apparatus would be huge. So now I'm thinking an absorption cooling system and some good reflective window tinting may keep me cool, and not use any gasoline. And I could toss all the weight of that broken A/C unit. hmmm...