Why do cars in America have daytime running lights de-activated? - U.S. Politics Online: A Political Discussion Forum

Danny · #1 (**permalink**) 06-03-2007

In Canada, since about 1991, most cars come with automatic daytime running lights. I think even around the world this is the case. That means it would seem to require more effort to make a change to vehicles to be sold in the US. Its a safety issue and an important one if you asked me. You are way more visible with your lights on even in the day.

I'm in Irvine , CA right now and I almost hit a guy leaving an undergorund parking garage because I didn't see him. My rental doesn't have driving lights either.

Why would Americans want to be less safe? Is there a reason for this?

bigTlilODD · #2 (**permalink**) 06-03-2007

Well, daytime running lights are good and all, but like all safety items like this, eventually you get use to it and it is no longer effective. This is why most places are changing the color of emergency vehicles from red to yellow and street signs are a different type of yellow.

I think drivers should pay more attention, rather than reallying on the automotive industry to make up something like daytime running lights or sensors that tell you when you're about to hit something.

Plus if one of those safety features fail, especially in So. Cal, there will be a huge lawsuit.

Maybe we should have 150db bells that ring constantly, so people will hear the cars too. That would be much more effective than having llights on.

Mrs. M · #3 (**permalink**) 06-03-2007

Some cars do have the daytime running lights but I guess until it's mandatory, we won't see it on all cars. Louisiana passed a law a while back making it mandatory to have the headlights on any time windshield wipers are required. I definitely like that law!
I found this article about the lights interesting:

Quote:

If daytime running lights were mandatory in the U.S., and all vehicles had them, how much extra gasoline would that use each year?

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.

Howstuffworks "If daytime running lights were mandatory in the U.S., and all ve"

proUSA · #4 (**permalink**) 06-03-2007

IMO all lights should automatically come on after the vehicle starts….There are far too many idiots that forget to turn their lights on at dusk or raining or both.

Just the other day, I was driving after dusk and it was down pouring, I almost t-boned a car that pulled out and had no lights on, the car was also a dark blue or black so it was nearly impossible to see. If I knew they had no children in there, I should have hit them just for being stupid !

Danny · #5 (**permalink**) 06-03-2007

Very interesting article Mrs. M.

PS: its beautiful here in Orange county / Newport Beach. I could get used to this. Too bad I'm going back to Montreal tomrow

Donkey_Left · #6 (**permalink**) 06-03-2007

My s-10 always has (albeit relatively dim) lights on.

pramjockey · #7 (**permalink**) 06-04-2007

Actually, the lights aren't de-activated. It's an additional part that's put on for the Canadian market.

Danny · #8 (**permalink**) 06-04-2007

Quote:

Originally Posted by pramjockey

Actually, the lights aren't de-activated. It's an additional part that's put on for the Canadian market.

Or removed for the US market

Anselme · #9 (**permalink**) 06-04-2007

In Belgium you have to, in France, I think it is recommended

In the roads in the forest... with the trees with a dark car, it is sometimes confusing whether there is a car or not...

underboss · #10 (**permalink**) 06-04-2007

Most Americans have something called "commons sense", when they're leaving or entering an underground a garage in the dark - they turn on our lights. Or if you drive some newer model cars like Toyota or a Lexus they usually come on if you have them set to "auto".

Most Americans do not like to rely on the government to mandate such things.