Headlights during the day.

[Snowball]

Today's press (Daily Mail) reports that a new EU directive has been agreed, which will require vehicle headlights to be switched on whilst driving during daylight hours. It says that the rules come into force in 2011 and relate to new cars. If this is correct as written, does it mean that cars already on the road will not have to have their lights on? I think not. I believe it probably means that, on new cars, it will not be possible to turn off the headlights without switching off the engine, and that the rest of us had better remember to switch them on.
But then again, in referring to this ruling regarding its effects on consumption of more fuel, producing more CO2, at the end of the article it comments that this threat is diminished by restricting the measure to new cars only.
So it appears that some of us will be driving legally without our headlights on, whereas others will be illuminated in order to be legal.
Who else but the EU mandarins could come up with this kind of dual standard?

A failed headlight bulb will then become another source of revenue (via number plate recognition cameras?), and you can bet the authorities will pursue that to the limits; e.g. catching drivers on a motorway, when a bulb has just failed and there is no place to safely stop and replace it.

[98selitb]

I can't see the point.

At the moment I'm in Italy, and I have noticed that practically every car, even on a sunny day, has their headlights on all the time. Maybe it is already compulsory here?

In Sweden, it is compulsory to have your headlights on at ALL times when driving. This is why every Volvo you see always has its lights on. This is a sensible rule for Scandinavia, where for geographical reasons the days can be short and very dark, especially in winter. But it makes no sense at all anywhere more than 5 or 10 degrees south of the Arctic Circle.

[MrDanno]

Does seem rather a stupid Idea for a country like ours, As Snowball said the extra fuel used to provide the energy to power the headlamps at all times would increase pollution and more importantly in my opinion - It would increase fuel consumption (more revenue for the tax pot).

I know some bus companies have a policy of headlamps at all times but, I cannot see how that makes it safer. If you can't see a bus coming then you need to get your eyes checked.

I remember this subject being in the papers in the early '80s.

Anyway, Alot of cars if not all new ones have a 'dim-dip' headlamp system that powers the dipped beam at around 20% of its normal output when the sidelights are on and the engine is running.

[Snowball]

Having started this thread, I am now beginning to carry out an autopsy on my first observations.
(1) Referring to my onboard computer, I have never really noticed any significant change in mpg when travelling the same route during daylight or darkness, when my headlights would be on.
Since the extra demand on the alternator acts like a brake, then this braking effect would be transferred to extra load on the engine. Given the mechanical advantage that the engine has over the alternator, I would imagine the extra load to be small. But as it exists, it must use a little more fuel.
(2) The ruling only applying to new cars from 2011 suggests very little improvement in road safety for some considerable time.
(3) Touching on points raised in another thread, about insurance costs, on the safety argument, are insurers going to rate the older cars less safe, since they don't have to/may not bother to switch on their headlights during the daytime?
(4) Isn't there a danger of this becoming a conflict of "how easily we must be seen" versus "how much we should use our eyes"?

[Rolebama]

I think there is a tie-in with what is probably the most common comment after a collision: "I didn't see you!". So driving round with headlights on, in a flourescent pink car with flashing neon lights and a brass band on the roof is probably next on the agenda, along with national speed limit of 4mph, with the addition that you must be preceded by a man waving a red flag.

[Rolebama]

By the way, the average headlamps being 55W mean a producing approx an extra 0.17bhp to account for a general usage of 130W (give or take a couple of dashboard lights), so cruising at 30mph you are probably increasing fuel consumption by about 2 - 3%. So much for reducing carbon footprint.

[Snowball]

That is for a static load, Rolebama. I think the kinetic energy produced by the vehicle would considerably reduce that load.

[Rolebama]

I base the figures on a need of 8 - 10bhp necessary to maintain a steady speed of 30mph, which is what I have been led to believe is necessay because of wind resistance, tyre friction, and mechanical friction within the drive train. The only time kinetic energy would take over, would be on overrun because of downhill gradients, or coming to a standstill. As most of our journeys necessitate the eventual return to our starting point, these are benefits are nullified as the gradients would have be ascended, and the initial pulling away. Even if the figures and/or my science is wrong, I am sure you get my drift.

[Snowball]

Well, yes. As nobody has yet solved the secret of perpetual motion, then there has to be a trade off of fuel for power used.

[galaxymadbaz]

THE BIG WORRY, as mentioned on other forums, is if dipped headlights are on permanantly on all cars, it negates the use of daylight running lamps (DRL's) on motorcycles and I'm sure there will be a rise in RTI's involving motorbikes. I was in favour for DRL's but when the above point was made I have to change my thinking, what they should do is make it mandoraty for automatic dipped headlights to be on when the windscreen wipers are on or heated screens or if outside temp is low.