Daytime running lights are coming
Daytime running lights are coming
Author
Discussion

dingocooke

Original Poster:

670 posts

243 months

Monday 30th October 2006
quotequote all
The euromeddlers want us to have headlights on all the time, heres an interesting piece of info from th enormally not so environmetal USA explaining the cost of such a proposal in the USA; not a carbon neutral move from brussels then??

quote:

For several years now Canada has required all new cars sold to have daytime running lights. Any time the car is running the headlights are on, but the taillights and other lights are off. You have to turn on these other lights from the dashboard at night. Studies seem to indicate that having the headlights on during daylight hours reduces the number of multiple vehicle accidents (although there has been some controversy about people forgetting to turn on their other lights at night -- a mistake that causes extra accidents, and a good example of the "law of unintended consequences"!).
The US has not adopted this law, but if it did they would definitely consume gasoline. Headlights require power, and a car's engine produces power using gasoline. If you make a few assumptions, it is possible to estimate how much gas the law would consume.

A typical headlight bulb uses about 55 watts; sometimes the daytime running lights run at a lower wattage so they use a little less power. Let's say the daytime running lights use 100 watts since there are two bulbs.

To calculate the energy used, we need to figure out how much time people will spend with their lights on. According the to NHTSA, vehicles in the US drove 2,560 billion miles in 1997. We need to make a guess at the average speed people drive including stops in order to figure out how much time people spent driving their cars. Let's guess 30 mph, which means each mile takes two minutes. That makes 5,120 billion minutes or 85.3 billion hours. Now if each car normally drives at night about half the time, that means that the daytime running lights would be on 42.6 billion hours a year. Multiplying by the 100 watts we get 4,260 billion watt-hours or 4.26 billion kilowatt-hours. The U.S. uses about that much electricity nationwide in 12 hours.

Now we need to figure out how much electrical energy we can get out of a gallon of gas. A gallon of gas contains about 60 kilowatt-hours of chemical energy, but this energy has to go through two conversion processes before we can use it in a light bulb. First the chemical energy must be turned into mechanical power by the engine of the car. Car engines don't do this very efficiently -- only about 25% of the chemical energy can be turned into mechanical power, and the rest is wasted as heat. After the engine gets done with our gallon of gas we have 15 kilowatt-hours left.

Now the alternator on the car has to turn the mechanical power from the engine into electrical power. The alternator does this a lot better than the engine, but it is still only about 70% efficient. In the end we get about 10.5 kilowatt-hours of electrical energy out of a gallon of gas.

To calculate how many gallons of gas this is, you can divide the 4.26 billion kilowatt hours of energy that the daytime running lights consume each year by the 10.5 kilowatt-hours of energy each gallon of gas yields. If daytime running lights were on all the vehicles in the U.S., we would burn an extra 406 million gallons of gas each year. That's only a couple gallons for each vehicle, but in total it is more than all of the vehicles in the country burn in a day. At $1.50 a gallon, that's $600 million per year. Looking at it another way, an extra 8 billion pounds of Carbon Dioxide would be added to the atmosphere by this law.

It's an interesting question because it shows how a simple idea like, "let's have everyone turn on their headlights all the time" can have a real cost when you try to implement it! Whether the benefit is worth the cost is an important question in almost any public policy decision.

Scraggles

7,619 posts

247 months

Tuesday 31st October 2006
quotequote all
EU wont care about the environmental cost of anything unfortunately - once one of their guys has a thing they want to do, it comes out soon.

my car has auto sensing lights that come on when needed and off when not. works fine.

what next snow chains in case it gets a bit icy or maybe have winter tyres and summer tyres like finland also has ?

rich 36

13,739 posts

289 months

Tuesday 31st October 2006
quotequote all
How about an assistant
replet with say... a red flag

to walk briskly ahead in urban areas,

where risk of collision with pedestrians
are most likely

jubileejim

153 posts

233 months

Wednesday 1st November 2006
quotequote all
I thought that there was a study done that found that headlight lights during the day can make a vehicle appear further away. If this is true then this law may actually increase accidents.

LuS1fer

43,204 posts

268 months

Monday 6th November 2006
quotequote all
Volvos had them for years. Not sure if they still do but is there any evidence they have stopped any accidents? I doubt it.

Podie

46,647 posts

298 months

Monday 6th November 2006
quotequote all
LuS1fer said:
Volvos had them for years. Not sure if they still do but is there any evidence they have stopped any accidents? I doubt it.


Certain countries legislate DRL's, so it's a legacy of that.

When I was living in Poland years back, lights had to be on between October and March when the engine was running...

aston67

872 posts

253 months

Monday 6th November 2006
quotequote all
driving on a motorway during the day when all the car are with the lights on is quite painful and distracting especially if you have to drive for long hours

also spotting motorbikes is more difficult



Edited by aston67 on Monday 6th November 12:50

vipers

33,408 posts

251 months

Tuesday 7th November 2006
quotequote all
aston67 said:
driving on a motorway during the day when all the car are with the lights on is quite painful and distracting especially if you have to drive for long hours

also spotting motorbikes is more difficult



Edited by aston67 on Monday 6th November 12:50


Motorbikes are a bloody nusience, I dont mind them having the headlight on, coz their a small target to see, but WHY DO THEY INSIST ON HAVING FULL BEAM ON IN DAYLIGHT.

Not wishing to tar all our motorcysle members with the same brush, but consider this, my volvo has an auto dimming rear view mirrow for nightime driving, but you cant manually dip it during the day, so a motorcyclist on FULL BEAM behind me is so BLOODY ANNOYING.

The first post re cars in Canada having front lights on and not the rear ones, is surely dangerous, whats to stop someone driving into the evening seeing their front lights on, and forgetting to put the rear ones on?

negative creep

25,794 posts

250 months

Wednesday 8th November 2006
quotequote all
is it me or are there a large number of bikes who also drive around with coloured lights? That's even more annoying. Anyways, I really don't see the point; a car with sidelights on in good light can be a distraction. If every car were doing it I can only imagine it would be worse

Plus, you'll get loads of muppets with their fog lights on at the same time

aston67

872 posts

253 months

Wednesday 8th November 2006
quotequote all
plenty of wan4ers in London with fog lights on as well!

they must have seen the Fast and the Furious once too many

tigger1

8,447 posts

244 months

Wednesday 8th November 2006
quotequote all
A lot of bikes have the headlight hard wired nowadays, there's no switch (can't give any explanation of coloured lights though, other than maybe it's to stand out as a motorbike amongst all the DRL's?)

So, how difficult would it be to produce a camera that detects a car running with no lights then?

Jared_m

252 posts

245 months

Wednesday 8th November 2006
quotequote all
I think they're a good idea... I first encountered them in Sicily when I noticed many drivers drove with the lights on. I could see cars in my rear-view mirror easily, even if the Sun was behind me.

Now, I often drive with dipped beams during the day because I do believe it improves my visibility.

It works in some parts of Europe, standard on all Volvos, obviously not a revenue raising scheme (unless the oil companies are behind it?), I think it makes sense...

negative creep

25,794 posts

250 months

Thursday 9th November 2006
quotequote all
Jared_m said:
obviously not a revenue raising scheme (unless the oil companies are behind it?



It's all a big conspiracy by the bulb manufacturers. They'll wear out quicker so we have to buy more!