VW TDI vs. Gas comparison

[trebuchet03]

Originally Posted by theunchosen

I didn't. LD50 measurements are taken over the lifetime of an animal.

Incorrect
LD50: The size of a single dose of a chemical necessary to kill 50 percent of the organisms in a specific test situation. Cite

LD is not reliable for long term effects and ignores secondary illness.

1800 grams In a single dose will not kill you right away. 1800 grams is just the point at which the lifespan is shortened.

Incorrect... LD50 is mean lethal does... 50% of all subjects died.

the .5 figure is the marked up number that refineries generate per gallon(which compared to avg mpg of diesel cars/small trucks does not meet the new emissions policies) was an estimate. Nevertheless that's minutiae, because even if it produces 10 grams per gallon there is still vastly more CO2 damage than NOx. original requirements were less than 1 gram per mile?(average was 23 mpg for diesels) so 23 grams per gallon average. Still more CO2 using diesel from the 80s. Diesel today is refined further to ensure that less pollutants are emitted if you just burn it in open air. Nevertheless since I am apparently not capable to calculate that number maybe you should tell me and we'll go from there.

Can you please cite?

Clean Air Fleets | Emissions Standards

So heavy duty diesels (which as Deelzer pointed are showing mpg reductions) and I think they're the largest consumer of diesel fuel... The first standard was 10.7 g/bhp-hr... Unfortunately, not the same unit... But, I imagine it's safe to assume that emissions just prior were either greater or matched.

So lets say a tractor trailer requires 50hp to maintain 65mph on the road (if you can find documentation for an actual number, I'd appreciate it). So in one hour, it produces 535g... Lets say 10mpg - that's 53.5g/mi * 295 = 15782GWP
CO2 would be 20lb = 9071g = 907g/mi * 1 = 907GWP Those number seem grossly far apart - but the standards of yore are vastly far from the standards today....

And where you quoted me. . . my first answer was not scrub CO2. It was to reclaim it. Reclaim means to rescue from an undesirable state. C02 emissions are undesirable states and changing them to something else could easily be construed as reclaiming them. So any emissions policies taken towards CO2 would be reclaiming them. I also addressed the idea of using bacteria or algae to convert it to something either not harmful or something useful.

My apologies But even that said - why not put forward higher mpg standards? CO2 is purely a symptom of a problem. Increase efficiency and reclamation won't be necessary. Having both would be awesome - but if I had to pick one, it would be higher FE but I'm not willing to release other emissions standards as a result.

Really, we both want the same thing here - lower systemic emissions.... But, we disagree on how to do it (which is fine and I'm happy the discussion has been allowed thus far). I want higher goals for emissions quality for both cars and refineries. But honestly, I'm having a hard time nailing down exactly what it is you want (I can see what you don't want, however).

[theunchosen]

Yep emissions for heavy duty diesels are producing more NOx than CO2. although you divided the grams by 10 instead of 65 miles traveled.

Yes the LD50 is administered all at once but the test for non-common application chemicals is over several hours testing periodically to check vitals on animals to see if more extensive testing is needed, but tests for more common chemicals Benzene for example is tested on vast numbers of animals over animal lifespan and includes larger mammals as well.

The LC50 of Benzene or the amount needed to cause near immediate death in 50% is over 3,000 PPM. Chlorine is 293 and most swimming pools are 5 PPM. Much closer to an LC50 than the air anywhere in the world.

Also most Chemistry TA's are going to absorb much more than LD50 of Benzene at some point in their career as well as hearty-doses on a monthly basis for anyone teaching organic. Its not that terribly deadly.

We both do want the same thing. All I am saying is that gasoline engines have a cat to weed out a few grams of HC at the cost of several MPG. if you snip that and improve exhaust efficiency(how fast can you get it away from the engine for free without breaking the valves) you drop the amount of CO2 you produce per mile because you get more miles per gallon. For instance if you did that on the above mentioned civic with variable trans you could probably get it to the 50-55 mark instead of the 40-45 mark. The noise regulations that mandate the engine has to go 4-2-1(also EPA) robs substantial amounts of power and FE, but if you still have a restrictive cat in place then it takes over and you see very small gains.

Pop, both port your exhaust out under the drivers side door(or passneger depending on exhaust and engine layout) with some baffles as it exits the car and you gain tremendous HP and MPG.

I originally thru-piped my cat and muffler for power gains and it was easily noticeable. Changing the exhaust pipes is a little harder and requires some fabrication because finding 4-1 pipes is difficult since its not legal for sound pollution reasons.

[tasdrouille]

Average diesel fuel price back below mid-grade gasoline nationwide

[NewTDI2010]

Hey guys ... maybe I'm lucky for being in a part of the country where I don't see the disparity of costs between diesel and gas, but $1 difference I've really never seen. Diesel is indeed more expensive than the low grade gasonile (regular unleaded), but in the mountain states Diesel is about .10-.15 centes higher (i've seen in the past as high as .25 c), but never $1 higher. If compared to premium gas, it's either the same or lower. If using these numbers, and considering the 30-42 mpg city/hwy for the TDI's, which is quite higher mpg than its comparable gas engine, the fuel cost savings is fairly significant, coupled with the fact that the diesel engine will simply last longer, I feel there's little comparison. Just my 2 cents ... no pun.

[arb]

Originally Posted by trebuchet03

So lets say a tractor trailer requires 50hp to maintain 65mph on the road (if you can find documentation for an actual number, I'd appreciate it). So in one hour, it produces 535g... Lets say 10mpg - that's 53.5g/mi * 295 = 15782GWP
CO2 would be 20lb = 9071g = 907g/mi * 1 = 907GWP Those number seem grossly far apart - but the standards of yore are vastly far from the standards today....

You are off by a factor of over 2x. My Jeep Wrangler requires 47 hp to maintain 65. All the big rig drivers I know say they get about 4.0 - 4.5 mpg hauling down the freeway.

Something to consider is the approach Detroit Diesel is taking with their current clean diesels - The DD15. It is a turbo compound that gets 10% free HP (50 hp) and an reduction of 5% fuel burn. It uses the same technology as the panicle in gas piston engines used in the last non-jet airliners - the Constellation - a turbo charger running the usual way, and an additional turbo down wind of the primary. This secondary does not have a compressor wheel to compress air, but rather is connected (serious gear ratio) to the crank shaft to convert lost energy out the exhaust into useful work.

My Dodge Caravan with a VW diesel gets 40 mpg at 70 mph, and 25 mpg hauling a large pop-up camper at similar speeds :-) GO DIESEL !!! Here its only 20 cents higher than low grade. so less than 10% - considering the 40% less fuel burn and 30% less CO2, I think its a bargain !!

[Bearleener]

My 2 Eurocents worth:
In Germany diesel has almost always been *cheaper* than gasoline, because it's subject to less fuel tax (presumably to help the truckers). As a result, people are buying diesels like mad, even in the smallest cars, despite higher purchase prices and higher vehicle taxes. As a result, demand for diesel is increasing and, because you can only get a certain amount of diesel out of a gallon of crude, the price disparity has recently been whittling down.
Diesel engines are inherently more efficient (something like 35% vs. 29%), but NOx and particulate emissions remain a problem. The latter is being addressed by particle filters, which fortunately are being delivered in most new diesel cars.

[arb]

There is a refiner in California that makes ONLY diesel fuel from crude oil. In the old school simple distillation method you get a set amount from a barrel of crude. In modern refineries, you do this first, than "crack" the longer chains to from what you want and link the shorter chains.

All this when so much EuroDiesel is being "Splash and Dashed" from our biodiesel laws ($1 per gallon for every gallon of diesel, no mention of the % of biodiesel - so entire tankers full of diesel have been brought here for a few gallons of our biodiesel so they get the $$$)

[roflwaffle]

Originally Posted by arb

My Dodge Caravan with a VW diesel gets 40 mpg at 70 mph, and 25 mpg hauling a large pop-up camper at similar speeds :-) GO DIESEL !!! Here its only 20 cents higher than low grade. so less than 10% - considering the 40% less fuel burn and 30% less CO2, I think its a bargain !!

Jeez, done already? I need to look up your thread on the GTD forums again! I gotta say, I do feel for that little 1.6l having to push around a Caravan.

[Peter7307]

[QUOTE=Daox;74924
How do diesel prices compare in non-US countries?[/QUOTE]

Here in Australia diesel is consistently higher than unleaded (gasoline) usually by about 6 to 10 cents per litre.

This has nothing to do with making the stuff either.
It is all down to taxation and other government charges.

Normally the costs for most diesel versions of the similar model are around 5 to 10 percent higher than their gasoline counterparts but it varies from maker to maker.

Cheers , Pete.

[Duffman]

Edmonton Gas Prices - Find Cheap Gas Prices in Alberta

Gas always come down in the winter while diesel goes up though. In the summer at the Flying J its usually 10 to 15 (as high as 19) cents per Litre (x3.78 to convert to U.S. Gal) lower for diesel.