Do Alternators Change in Engine Load?

[LaneLester]

I've seen more than one person recommend the reduction of electricity consumption (stereo, lights, etc.) as an FE technique. I thought the alternator's load on the engine was a constant factor, and if so, those recommendations do not make sense to me.

Is the alternator's load on the engine different, depending on how much electricity the vehicle is using?

Lane

[gascort]

Originally Posted by LaneLester

Is the alternator's load on the engine different, depending on how much electricity the vehicle is using?

Yes it is. The magnetic field within the alternator is controlled by altering the amount of current through it. If this didn't happen, idling your car with your lights and stereo off would overcharge your battery.
If you want quantifiable evidence of the variable load electronics put on your car, ask someone with a huge stereo to take you for a ride. If they turn on their amplifier while cruising, you feel the hit the car takes (almost like turning on the a/c).

[RiseAbove]

My Cavalier has those daytime running lights that never go off. I have been meaning to kill the damn things. Need to do that soon.

[LaneLester]

Thanks for the education, guys. I was thinking it was like my solar panels and batteries, where the maximum juice comes into a controller that varies what goes to the batteries.

Lane

[MazdaMatt]

If leaving your drl's on prevents 1 accident in your entire life, it will pay for the minute droplets of fuel used to run them. Be smart, drive safe.

[dcb]

You might quantify it a little better than "minute droplets".

Let's say you have 75 watts worth of DRL, that is equivelent to 1/10 of a horsepower, plus it comes through your alternator so it is probably more like 1/5 hp to run the DRLs.
I think we need more efficient lighting (but not blue please). If you consider there are about 125 million cars on the roads in the US alone, that would be 25 million horsepower to run DRLs on all those cars!

They don't do so good a job preventing accidents with other cars but they do seem to help out bikers and pedestrians a bit (AFAIK)

[MazdaMatt]

Give me the value of a dead pedestrian and I'll crunch the numbers to see if they are worth it for you...

[dcb]

There is no end to that sort of logic though. How much would it cost to wrap everyone in foam rubber? How many lives would it save? Eventually we WOULD all never leave the house.

[greenitup]

Originally Posted by MazdaMatt

Give me the value of a dead pedestrian and I'll crunch the numbers to see if they are worth it for you...

the average american human life is valued at i believe $6.9 million dollars. (gov't calculations)

[MazdaMatt]

No, there's an end to the logic.. if it was hypothetical, and you thought people were worth infinate money, then there's no end. Lets take 6.9 million dollars. That buys about 6 million litres of gas. That powers my DRLs for a long time. Drive smart, be safe.

[dcb]

So you accept the 6.9 million figure then?

[MazdaMatt]

Make it any figure upwards of 500 dollars and its probably still worth it.

[dcb]

Ok, now tell me the cost of implementing every safety related idea that was ever conceived on every vehicle, since you have not defined an upper limit on the value.

[dann_04]

I think we have strayed a bit from the topic...but quick question aside from the value of a life, on older cars they used generators which always make voltage no matter what speed they are spinning, unlike the alternatoer which has a cut in speed. So would a generator vary the load on an engine depending on the watts used? and if not is that a viable option to swap out a generator for an alternator? Seems like a better choice than some of the people who are dropping the alternator all together. I dunno, discuss.

[MazdaMatt]

Yes, i understand that if you wanted to prevent 100% of automobile related injury/death, you could wrap your car in a billion dollars of safety gear and its not worth it. However, something so simple as leaving your drl's on is cost effective enough for the slim likely hood of running someone down. Think "law of diminishing returns" on this one. The savings in fuel for a hundred people turning off their DRLs could be acheived by one person scrapping their H2 and buying a metro (massivly conservative estimate).

[dcb]

Can we TRY to be a little more respectful guys? BDC, if you have some actual data you would like to share then please do so. I don't like putting people on auto-ignore in case they actually say something decent, but it's an option: http://ecomodder.com/forum/profile.php?do=ignorelist

[justpassntime]

Lights don't save lives, just ask a moth or a deer!

What about the DRLs that come on at night and with no taillights and people think they have their lights on? How many accidents do you think this has caused?

Oh, back to the original question.....try idling your car at night and turn your headlights on and one at a time turn on all your accessories and watch the headlights dim and the engine noise change.

[dcb]

Do YOU have any data on that? Or should we just speculate AND call each other delusional (and fools)?

[dcb]

"International regulators, primarily in Europe, are struggling to balance the potential safety benefit offered by DRL with the increased fuel consumption due to their use"

I think that is basically where we are at too. I had put a couple inexpensive warm white LED clusters on my bike but they didn't last. I will probably try again with more LEDS, and a regulator this time

I do feel like I'm pressing my luck every time I pass a cop with the headlight off, less so when I have auxiliary LED lighting, but it still not a guarantee of an equipment related ticket.

[dcb]

Well you felt so strongly about it I figured I'd ask if you had already done the research about the actual number of lives saved (and their categories) that you could share.