Posted on 07/06/2005 8:33:43 AM PDT by skyman
Youre right. I did not explain my point very well. But there most certainly is "waste," at least in this engineer's opinion of what "waste" is. And yes, if you disconnect all loads, no mechanical loss thru the alternator occurs. But my point is that these chips are more efficient (so I hear, I'm still skeptical about them) than running freon compressors. In which case, not as much of a load is required, which pushed you up on the efficiency curve, thus conserving energy.
It's hard to explain, and I don't know the ins and outs of what these kids are exploring. None of us do. So I don't think we should slam it, as many people here are doing. At the very least, it's a learning experience.
You are right about weight and compexity savings. I don't belive the energy savings numbers but it would certainly have fewer parts to fail. I think I will build one for my old '88 with a blown compressor.
"No matter the electrical load you place on the alternator the engine will NOT work harder. "
You are completely mistaken. Study some stuff about electrical motors and you will quickly find out.
A simple experiment will prove it, also. Go out to your car and start it, leave it idling in Park. Turn the headlights on and off, noting the change in load on the engine.
Headlights take a significant amount of current and on some cars it's really noticeable when the current draw increases.
You are not just wrong, but deluded to think that once you overcome friction for a given sized generator, the mechanical load is otherwise independent of the electrical power delivered. It's akin to saying that a car engine consumes no more fuel idling at a given RPM, than it does towing a heavy load in high gear at freeway speed, with the same RPM - after all, the friction in the engine is just the same in both cases.
"Top sends"
I think you said it again for me. :)
Forgive my ignorance, but what is "Top sends"?
sorry, forgot my /s tag (which is for wimps! =P) on my last post when i said to quit embarrassing yourself. but i was addressing something else you had said.
and yes, there is electrical loss. just as there is mechanical loss. Chrysler (i believe) has been tinkering with electrical recovery from when the alternator is spinning harder than it has to, yet has not yet slowed to where it needs to be, for instance, when you drop from pulling a high load to a lower load. If we could harness that energy in between, that would help efficiency.
There is probably a formula somewhere to figure watts, horse power, or BTU usage or something, to figure the probability of this working or not. Kinda like a 100 mpg carburetor or something. Most people that make this claim have never figured it would take 150% efficiency to move a SUV down the road at that mpg. Most engines are good to get 40%-60% efficiency. A moped might get it, but not a Tahoe.
Well, sunlight is about 1 kW / square yard, and 1 HP is ~750 W. So the heat load on an SUV that's two yards wide and three long, or six square yards, is about 6 kW. Assuming 50% efficiency, it would take 12 kW to clear the heat, which can be expressed either as 16 HP (12 / .75) or as 1000 A at 12 V. (That's quite an alternator!)
I'm most definitely automatively challeneged, but pelase explain all this talk about alternators?
I was under the impression that the initial charge to turn the engine over came directly from the battery, with the alternator merely carrying the load until the generator spun up to speed, at which point, the alternator still spins, but does not generate power. It is the generator which then creates the electrical energy necessary to run the engine (and accessories) and recharge the battery.
Am I wrong, and if so, please enlighten me?
Engines can consume vastly different amounts of fuel at the same RPM, e.g. idling vs. towing a large load uphill. You really, really don't know what you're talking about.
Huh? Of course it does.
Alternator = generator. Only works when the car is running, so you need a battery to get it moving in the first place. After the engine gets going, the alternator handles all electrical tasks, including recharging the battery, until the engine goes off. The issue arose because the Peltier effect devices run off DC power. Lots and lots of DC power.
Heck and here I was thinking they were two seperate things. Thanks much!
Your statement that increasing the electrical draw on the alternator doesn't increase the power needed (and fuel needed) to turn it goes beyond stupidity.
If your idiotic statement were true, then you could hook an arbitrarily large electric motor to the alternator and run the car and the alternator both off the electric motor. This is called perpetual motion, and rational people don't believe in it.
OH and don't even both with more of your bs. I'm already broken my rule about arguing reality with drunks, religious wackos, NASA lovers, and other head cases
I hope you enjoy walking.
So... they are dumping the heat where? outside? on a hot day? Efficient? Some kids need to look up the word and learn how to calculate it.
thats exactly what I was getting at; efficiency. good explanation, much better than mine.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.