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I may not be able to measure it, but creating energy to light the lights uses some power.
746 watts = 1 horsepower. The fog lights draw 55 watts each, 110 watts for the pair, or 0.15 horsepower. Since alternators are about 50% efficient (50%-62% dependent on speed, but I'm using the lower number due to other losses within the electrical system between the alternator and the fog lights), running the fog lights consumes around 1/4hp to 1/3hp. Even if it's the worse of the two numbers, that's still only about 0.4% of the engine's output. But it will result in worse fuel economy. Whether it's measureable is doubtful, but it will have some impact.
 

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746 watts = 1 horsepower. The fog lights draw 55 watts each, 110 watts for the pair, or 0.15 horsepower. Since alternators are about 50% efficient (50%-62% dependent on speed, but I'm using the lower number due to other losses within the electrical system between the alternator and the fog lights), running the fog lights consumes around 1/4hp to 1/3hp. Even if it's the worse of the two numbers, that's still only about 0.4% of the engine's output. But it will result in worse fuel economy. Whether it's measureable is doubtful, but it will have some impact.
A+, Gold Star, Head of Class
 

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A maximum loss of a third of a horse power is a long way off of 3bhp.

Yellow light will penetrate fog better than white as it has far less of the blue spectrum which is prone to defraction in the water droplets in the air... however, fog lights are designed to light up the ground nearest to the car so you can keep on the road.

Good luck with the HHO project. I think it's snake oil to be honest but I'd love to be proved wrong. Scientists and Physicists would love to be proved wrong too.
 

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A maximum loss of a third of a horse power is a long way off of 3bhp.

Yellow light will penetrate fog better than white as it has far less of the blue spectrum which is prone to defraction in the water droplets in the air... however, fog lights are designed to light up the ground nearest to the car so you can keep on the road.
If you went to the link I posted, the two mechanics said all about the fog lights and the myths and what not. Yellow decreases the light as far as they said. Not sure if it's true, but definitely read the post. They have been mechanics for Long time.

Good luck with the HHO project. I think it's snake oil to be honest but I'd love to be proved wrong. Scientists and Physicists would love to be proved wrong too.
As for the HHO, had someone comment to me in PM that you loose energy. Well that is what the Scientists and Physicists say. Ok, here is what I told an engineer at work.

"Who cares if it takes more energy to create energy!" It is not about the energy that you loose but the gas milage that you get out of it. Engine works a bit harder, but if I can get 500 miles to the tank out of the old 350 miles to the tank. And I am using a little bit of distilled water and baking soda. Who cares. I am saving my money and it's not costing me much at all.

Hope you see my point. Grant it, we are still working on a good prototype. We are dealing with heating issues and what not. Trying to get the current down, heat down, and output of HHO up. So, like I posted awhile back, I think, if we do succeed, I will post my results. But, I won't be posting or even installing into my smart until I have confidence in it running in my 95 F150 for a bit. Would hate to damage a new car. If you get my drift.

Have a good day all. :)
 

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Do people really overanalyze this car so much that they need to debate how much energy a fog light uses? It's a $12,000 disposable car that's shorter than a loveseat and holds two people. It's not the Space Shuttle. And, frankly, how much do fog lights get used? A few times a year, for a few hours? If it's so foggy out that I need my fog lights, I really don't care if they cause me to get FOUR miles to the gallon: it's a piece of equipment designed to help keep you alive under certain conditions. I'll gladly give up the few dollars for a gallon of gas if it keeps me from hitting a car or animal in front of me during bad fog. JMO.
 

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Inquiring minds want to know, I guess. I learned a few things off this thread, as I do in many others in this forum. I'll scroll down faster or click to another thread if I want to skipherphew... :)
 

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A common mistake: the alternator doesn't "kick on.." the alternator doesn't have a clutch and is ALWAYS connected to the engine via belt and wheels, it's always revolving according to rpm but not according to electricity charge or consumption. SO NO IMPACT AT ALL ON MPG
The alternator "LOAD" does vary dependent on what electrical accessories it needs to supply power to, thus, while it does not have a clutch, it will get it's 'power' fro the engine - some gas is consumed for non-motion purposes.....
 

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The alternator "LOAD" does vary dependent on what electrical accessories it needs to supply power to
Thank you. I wasn't positive on this, although I suspected it. From experiencing a loose belt begin to squeal when headlights were switched on. (in other cars, no loose belts in my smart :))
 

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skipherphew?¿
I caught it. You obviously are down on the beach - up north a few miles more and you'd catch right on. :p

Skipherphew of dem dare mindless rambins' we sumtimes doo. :D Now back on to the subject of foglights (or are they driving lights???....) and why they are so good - bad - horrible - great - mediocre - awesome - or whatever......
 

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I usually work things out in my head to see if it makes sense.

the load on the alt thing goes like this.

I notice that under extreme load the alt works harder. I think back to when one of my vehicles had a loose fan belt and when the headlights were on it squealed because of the increased load. that load is some resistance. that requires some power to turn it. that will reduce the milage.

I may not be able to measure it, but creating energy to light the lights uses some power.
YES, but your alternator does the same work always , depending on the rev speed sure, but it is ALWAYS connected to the engine not just when you put your lamps on.... ....
 

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YES, but your alternator does the same work always , depending on the rev speed sure, but it is ALWAYS connected to the engine not just when you put your lamps on.... ....
Sorry, but you're mistaken. The amount of force needed to turn the alternator is related to the amount of current that it is being asked to supply. When you draw more current through your car's electrical system (fog lights, headlights, stereo, tail lights, turn signals, HVAC fan, wipers, rear window defogger, heated seats, etc.), the engine has to work harder to spin the alternator -- either to supply the current in real-time or later to recharge the partially depleted battery.
 

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So, when cruising at constant rpm I should see the revs go up when the lights are turned on? :)
 

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No, but you will require more power from the engine (more gas) to maintain that RPM as load increases. It's like the load you feel when the A/C compressor cuts in and out only much more subtle.

So, when cruising at constant rpm I should see the revs go up when the lights are turned on? :)
 

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No, but you will require more power from the engine (more gas) to maintain that RPM as load increases. It's like the load you feel when the A/C compressor cuts in and out only much more subtle.
exactly! if you have ever used an exercise bike with magnetic braking, its the same concept, the load does increase with increased consumption.
 

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exactly! if you have ever used an exercise bike with magnetic braking, its the same concept, the load does increase with increased consumption.
That was an absolutely superb analogy! I struggled with several, never finding one that really was right. Thank you.
 

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my wife made an intersting observation at dusk yesterday - as she closed the power windows, the lights dimmed. not much margin for electrcity generation on this car.
 

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Obviously, you did not read my post much at all. It has been tested on SEVERAL Cars. You can rev the alternator and it is turning all the time, but if the voltage is going to the battery and if it's driving a load are two differnt things. We have tested it on several cars, and as soon as DL are turned on, MPG drops 1 - 3 depending on the car.
Ho hum another Internet scammer, HHO my ass, snake oil for the 21st century.

Illuminated fog lights (HB - Halogène Brouillard) consume exactly 110W, which is 0.15 horsepower. At your "measured maximum" loss of 3 MPG per 0.15 HP, a 35 MPG car would be losing 20 MPG, that is, achieving 15 US MPG - when the wipers are on high speed, the heated seats are on, the headlights and fog lights are on and the stereo is on.

Turning the rear window defroster on would probably reduce that to 12 MPG :rolleyes:

But then the HHO kit you will sell us would increase that to 271 MPG. Boo yeah.
 

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Them Driving lights are not real FOG lights. Real ones have a yellow case. Those be Driving lights.

Ummmm..... No.

Whether a lamp is a driving lamp or a fog lamp has nothing to do with the lens color; it has to do with the pattern of the light projected from the lamp and their mounting location on the front of the vehicle... Fog lamps are wide, flat, fairly short-throw beam pattern, mounted as low to the ground as practical to shine underneath the fog bank. Driving lamps have a rounder, narrower, longer-reaching beam pattern, mounted higher up, usually in the same plane or higher as the vehicle's headlamps so that they can project light further down the road.

There are yellow-lensed driving lamps and clear-lensed fog lamps. Go watch 24-hr touring-car rallying some day and you'll see road illumination taken from science to art.
 
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