I don't really mind if it's on cars that now have them (though still think it's become a case of well, Audi fit them so every other manufacturer wants to follow suit because somehow it's considered cool by the Proleteriat) , but really don't see a need to retrofit. For example I wouldn't be seen dead with a third/high level brake light on my current car as it didn't have one as standard.

Soon we'll have flashing lights on our cars, then everyone (well at least on here) will want to retrofit them.

If you can't make appropriate use of the correct lights at say dusk or at night, then you are an idiot basically.

Did you know driving with your headlights on all the time wastes fuel? they make your altenator work harder "So using more fuel" and the cost of fuel now i dont think its worth it?

Bri said:

Did you know driving with your headlights on all the time wastes fuel? they make your altenator work harder "So using more fuel" and the cost of fuel now i dont think its worth it?

Click to expand...

and when you die because some idiot doesn't see you?

Having your lights on uses a minimal amount of fuel.

trackdayqueen said:

If you can't make appropriate use of the correct lights at say dusk or at night, then you are an idiot basically.

Click to expand...

Amen to that. At least compulsory DRL's mean that everybody will be visible at least to some extent at all times of the day.

Bri said:

Did you know driving with your headlights on all the time wastes fuel? they make your altenator work harder "So using more fuel" and the cost of fuel now i dont think its worth it?

Click to expand...

Lol! I doubt it's a noticeable amount.

Tbh our with our Classic Pandas we just go around with the headlights on all the time, but they're a 60 second job To change the bulbs on, which do blow slight more frequently due to being on all the time, the we Pandas however though and my Stilo, headlight bulb changes are not 60 second job to change (not sure about on the 500) and changing them at the rate they normally blow is enough of a headache.

DRL is a useful safety feature. On a sunny day headlights are not that visible and noticeable. Furthermore constantly running with headlights would require more frequent bulb replacement and probably some waste of fuel.

The good feature of proper DRL - they are noticeable by crossing pedestrians and other drivers and that exactly what you need on the road. However, to achieve that you need powerful LED DRL. Cheap Xmass tree decoration LEDs may look nice, but useless from safety point of view.

Or..................just always drive with your lights on like I have for the past 20+ years. Then you'll get all the helpful folks flashing you to tell you have your lights on.

Click to expand...

Like AB100, I just drive around with my headlights on 24/7. You could argue that the extra electrical power will reduce your fuel consumption - but really is it enough to worry about?

John

I just changed the headlight bulbs in my MJ, they lasted for 3½ years and I always have the headlights on. Properly aimed headlights are every bit as noticeable as DRLs.

A new set of brand name H4 bulbs costs less than £10 and take about 5 minutes to change. I can live with that, considering I only have to do it every 3-4 years or so.

Consider the power usage. H4 bulbs use 55W on the low beam. A 1.2 Panda's engine develops 44000W. The power usage is negligible.

lesnick said:

...constantly running with headlights would... probably some waste of fuel.

Click to expand...

I bet you like watching the movie Apollo 13?

lesnick said:

DRL is a useful safety feature. On a sunny day headlights are not that visible and noticeable. Furthermore constantly running with headlights would require more frequent bulb replacement and probably some waste of fuel.

The good feature of proper DRL - they are noticeable by crossing pedestrians and other drivers and that exactly what you need on the road. However, to achieve that you need powerful LED DRL. Cheap Xmass tree decoration LEDs may look nice, but useless from safety point of view.

Click to expand...

I'm sorry but that's rubbish.

Firstly, the amount of fuel burnt to power headlights is minimal.

Secondly, headlights are noticeable, hence why in countries like Finland your headlights have to be on all the time whilst you're moving. Our Subaru always has its headlights on as it's green and being in a green part of the world it tends to blend in which isn't good. Headlights on makes things much more safe.

306maxi said:

Our Subaru always has its headlights on as it's green and being in a green part of the world it tends to blend in which isn't good.

Click to expand...

My Panda is grey and being in a grey part of the world it tends to blend in...

That's the urban jungle for you!

306maxi said:

Firstly, the amount of fuel burnt to power headlights is minimal.

Click to expand...

Not perhaps as minimal as you might think. On dipped beam, the additional load is about 135W; roughly equivalent to running with the heated rear window on continuously.

Comparing my own single-trip mpg figures, driving with the headlights on increases fuel usage by around 5% & is a significant factor in lowering fuel economy during the winter months.

Serious ecoDrivers will notice greater differences as the extra fuel needed to power the headlights is simply a function of the time you have them switched on.

I'm not for a moment advocating driving without the appropriate lighting for the prevailing conditions, but using lighting when you don't need it wastes petrol unnecessarily.

DRLs have their place in making the car more visible in marginal conditions but IMO making their use mandatory is just another piece of daft bureaucratic nonsense. Driving down the M1 in brilliant sunshine with the lights on is in my mind the motoring equivalent of running your central heating in summer with the windows open.

At the rate we're going, it'll soon be mandatory for pedestrians & cyclists to wear a high vis jacket whenever they are within 25 metres of a public highway

Dipped beams are 110watt together and affect the fuel consumption by nowhere near as 5%.

Winter driving using more fuel is normally down to longer warm up periods and people driving slower in snow etc and normally doing it in incorrect gearing.

I've tracked my MPG for the last 5 years and my father even longer and there is no significant difference in consumption at all between when driving with no headlights on during the day, to having them on 24/7 to then running with LED DRLs.

I'm not saying headlights being on doesn't use more fuel, buy certainly not enough to make it noticeable, same as AC. A common urban myth that your MPG drops to -12 when it's switched on.

jrkitching said:

At the rate we're going, it'll soon be mandatory for pedestrians & cyclists to wear a high vis jacket whenever they are within 25 metres of a public highway

Click to expand...

It might even be sensible if we're heading for a visibility arms race where you'll get run over if you're not lit up like a Christmas tree.

Most Easterly Pandas said:

Dipped beams are 110watt together and affect the fuel consumption by nowhere near as 5%.

Click to expand...

135W is the additional electrical load you'll see if you turn the lights on. remember you also need to add in the power consumed by the side repeaters, rear lights & numberplate light.

I've taken careful measurements on both 500 and Panda & stand by my mpg reduction figure.

Fair play on the 13watts, I'd forgotten to take into regard the other lights that come on with headlights.

Most Easterly Pandas said:

Fair play on the 13watts, I'd forgotten to take into regard the other lights that come on with headlights.

Click to expand...

In fairness to you also, the difference will be much less for a larger car, or for a Panda/500 driven more enthusiastically.

TBH I was surprised to find such a great difference when I first started to take notice of such things and at first didn't really believe it myself. Thinking it through, though, theoretical calculations would seem support the figures I've observed. Taking account of generator losses, that 135W will probably put about an additional 250W load on the engine. Now I'm guessing a little here but it wouldn't surprise me if the latest ecoPandas can maintain a steady 50mph on 5kW of engine power - and there's your 5%!

Another way of looking at it is to think about the fuel burn. My Panda can return about 60mpg overall in mixed driving at an overall average speed of around 30mph, so it's burning about half a gallon of petrol per hr. A gallon of petrol has an energy content of about 150,000BTU and a petrol engine will typically convert about 20% of that into useful energy. That's 15,000BTU/hr, which is around 4 1/2kW - and if I'm losing 250W of that to power the alternator when the lights are on, there's my 5% again.

Power requirements increase roughly as the cube of the speed, so cruise at 70-75mph & that 5kW becomes more like 15kW, and then that additional load of 250W will have far less significance & I doubt you'd be able to measure it.

Once you start moving into the rarefied world of the 60mpg petrol car, the little differences really do get magnified!

jrkitching said:

Taking account of generator losses, that 135W will probably put about an additional 250W load on the engine.

Click to expand...

Electrically it wouldn't as the alternator should be at least 80% efficient. But there's drag off the drive belt added to that as well.

Something Hyundai do on the i20 and the 1.0L i10 is where possible the alternator only provides power on engine overrun. This must go some way towards the i20's 119g/km C02 which is pretty impressive for a Punto sized car without start&stop.

Geddes said:

Something Hyundai do on the i20 and the 1.0L i10 is where possible the alternator only provides power on engine overrun.

Click to expand...

Think I've mentioned this before but that's a simple and effective way of squeezing a bit more efficiency out of the car - a sort of 'poor man's hybrid'. Fitting a heavy duty battery and permitting it to discharge to 50% of capacity, combined with smart generator control software is IMHO the way to go.

Drifting off topic but another thing I feel carmakers could do is to improve performance during warmup in colder climates - thermostatically controlled radiator shutters being one example. In a typical UK winter, a small commuting car probably only spends a small percentage of its time running at an optimal temperature.