Daytime running lights

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Daytime running lights

What do you think of daytime running lights?

  • Great idea

    Votes: 13 46.4%
  • Bad idea

    Votes: 11 39.3%
  • Leave me alone I'm sleeping

    Votes: 4 14.3%

  • Total voters
    28

FDF

Marea Scrappaged :(
Joined
Apr 30, 2007
Messages
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Keep your lights on all the time you're driving, heard this morning it could cost the average motorist an extra £64 per year in fuel.

I think it would be good for safety but very annoying because a lot of people don't have their light adjusted properly. Might see an increase in rage.
 
Road Safety Authority here encourage leaving dips on all the time and mis-aimed is one of the biggest causes of failure of the NCT so its checked at services, etc.
 
How would it cost more petrol :confused: i have my sidelights on all time because thats how its set on my car.

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The lights are powered by the engine, the engine uses petrol. When you switch the lights on your engine uses a tiny bit more petrol than if they were off. Thats what I was told :)
 
I dont know, but IMO light bulbs are going to use such a small amount of power the effect on fuel would but negligable. IMO. i put my lights on when conditions are anything but perfect, i used dipped because i dont see the point in sidelights, you can hardly see them.
 
Hmm, mixed feelings.

Positive - idiots won't be able to drive around with no lights on.

Negative - more bikers may get knocked off as drivers get used to seeing lights during the day and don't notice them any more.
 
What am i missing here? Alternator charges battery, but the alternator is being driven constantly by the belt, therefore I can't see how using the lights uses any more fuel.

If the alt was driven from a clutch then yes you could disengage it and then it won't spin when not needed.

But I can't see the 'uses more fuel' argument on the majority of cars.

Or am i being thick? Its been a long day.
 
What am i missing here? Alternator charges battery, but the alternator is being driven constantly by the belt, therefore I can't see how using the lights uses any more fuel.

If the alt was driven from a clutch then yes you could disengage it and then it won't spin when not needed.

But I can't see the 'uses more fuel' argument on the majority of cars.

Or am i being thick? Its been a long day.

The alernator has more resistance when the lights are on so uses more of the engine to turn it. but like i said IMO its a completely negligable amount
 
dipped lights is a good idea.... but why on earth do chavs leave their fogs on:bang:

Because they are ignorant :tosser: and attention seeking morons who FAIL to understand the difference between fog and clear driving conditions! If they need to attract attention by having front fogs on then they're obviously attention whores.
 

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What am i missing here? Alternator charges battery, but the alternator is being driven constantly by the belt, therefore I can't see how using the lights uses any more fuel.

Switching on the lights (as with any electrical circuit) creates a load and a greater demand for electrical power. This causes a greater draw of current from the battery, which in turn creates a greater demand from the alternator to keep the battery charged up to predetermined levels. If the battery is fully charged then the alternator effectively switches off electrical generation, which reduces the charge in the windings (an alternator consists of electrical windings on a rotating shaft housed by magnets). This then reduces magnetic resistance, which in turn causes a reduction in drag from the alternator pulley to the crankshaft pulley. This reduces the load on the engine, which over time means that the engine will use less power over set driving conditions. It's also one of the reasons why cars in the UK tend to be more uneconomical during the winter as they tend to have lights/ heaters on more so than in the summer.

An analogy is to think of a car driving along a flat road and then driving up a hill. The flat road is "lights off", and the hill is "lights on". To go up the hill the engine needs more energy to keep the car in motion when compared with driving on the flat. Once you've gone up the hill and reached a level gradient again the engine needs less energy to move the car compared with going up the hill. It's very much a question of supply and demand of energy.

As per the laws of physics, you cannot create energy out of nothing. You can only convert it from one form to another, so to generate electricity you are converting a small amount of engine power into electrical charge via the alternator. Over a year this is significant enough to add a noticeble cost on your fuel bill.


:)
 

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Can I put that simply Chas? :D
When you turn your lights on it increases current flow in the system. The more current an alternator puts out the more effort is needed to spin it...more effort means a bigger demand on the engine and as such more fuel is burnt.
Flick your main beam or HRW on at tickover and you will hear the engine revs drop slightly, this is due to the alternator loading up and slowing down the engine.
 
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Can I put that simply Chas? :D
When you turn your lights on it increases current flow in the system. The more current an alternator puts out the more effort is needed to spin it...more effort means a bigger demand on the engine and as such more fuel is burnt.
Flick your main beam or HRW on at tickover and you will hear the engine revs drop slightly, this is due to the alternator loading up and slowing down the engine.

That's what I meant, but I used 500 more words to say it! :eek:
 
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