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I want one of those manly Vauxhauls.
I applaud the OPs thoughtfulness. I trust you also apply the handbrake whenever stopped to avoid dazzling those waiting behind you with brake lights? Some of the newer Audi & Merc ones are so bright they make me feel nautious.
Saves fuel to run sidelights only on my car.
Ok, sounds likel it's time for a quick fag packet calc. Sidelights are 5w. Dipped headlight 55w. So 100w extra for two.
The efficiency of an engine in converting fuel to electricity via the alternator is around 20% (so says Google). So that 100w extra output needs 500w extra input.
A litre of petrol has around 34.5MJ of energy in it. the lights need 500 J/s. So a litre of fuel would in theory power the extra lights for 69,000 seconds. Or 19 hours ish. Assume fuel is £1.30/l. That's around 7p an hour saved in fuel if you drive round with side lights instead of dipped. Don't spend it all at once!
*These numbers might not be right 😁
Ah but you’re forgetting aerodynamics.
ADH that Lancia has working headlights? 😉
"Ok, sounds likel it’s time for a quick fag packet calc. Sidelights are 5w. Dipped headlight 55w. So 100w extra for two."
"So a litre of fuel would in theory power the extra lights for 69,000 seconds."
What if the poster has a Zoe or a Tesla ?
Or if switching on too many luxuries, such as lights sees the Voltmeter dive through the floor. Causing a petrol car to run out of electricity.
What if the poster has a Zoe or a Tesla ?
He doesn't, or he wouldn't have said:
Haha, have got to admit the fuel consumption thing did cross my mind, but only in a theoretical sense, I definitely notice the engine note changing when I run AC etc.
Or if switching on too many luxuries, such as lights sees the Voltmeter dive through the floor. Causing a petrol car to run out of electricity.
Then it's new battery and/or alternator time
thatll be the OP but not the guy suggesting he uses more fuel .
he may also have a dynamo and thus limited electrickery
I trust you also apply the handbrake whenever stopped to avoid dazzling those waiting behind you with brake lights? Some of the newer Audi & Merc ones are so bright they make me feel nautious.
Unfortunately on the Merc the brakelights are linked to the automatically handbrake. Hence you can pull up to the traffic lights, putting your foot on the brake will automatically put the handbrake on in the 'Hold' position and leave the brake lights on.
I guess Audi uses a similar system.
Even at 20mph, I wouldn't want to lose the benefit of being able to see reflective stuff.
do we even have cateyes on a 20mph residential street
Not generally, but I did encounter a pair of cat's eyes riding through my village last night. I wouldn't have seen the moggy at all without throwing some lumens up the road.
I'd rather meet someone with side lights on than the numpties that are stuck on main beam.
ADH that Lancia has working headlights?
Amazingly, yes. They're about the only electrical system on the car which does work ... and it is 5 years since it last passed an MOT ... but all the lights work fine 🙂