I know nothing about the technology...
So obviously it burns much cleaner overall since it gets such huge MPG. But for the amount of Work per combustion cycle, is it also cleaner there as well?
Nice fuel saving solution!
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I know nothing about the technology...
So obviously it burns much cleaner overall since it gets such huge MPG. But for the amount of Work per combustion cycle, is it also cleaner there as well?
Environmentally, it's an issue. Financially it's not, and that is the only reason you don't see a lot of cars with amazing fuel economy.
Bigus Dickus
Regular
"A few seats and whatnot"?
You mean adding 1000 to 1500 lbs to make it comparable to the average small to mid size car the average person buys. And you think doubling the weight and significantly increasing drag coefficients will increase fuel consumption only 20%? Think again.
Give me a good, efficient 180 hp gas engine, and let me design you a three wheel vehicle with very low weight (at 1.7g I'm thinking very little suspension either), extremely aerodynamic if unpractical body, a pair of seats, no cargo room, no amenities, no safety equipment, no regard for noise or ride... and we'll see what kind of fuel economy I can generate. Give me diesel and it will be even better.
As Gubbi said, size/weight and drag play a substantial role in those figures. You should probably be comparing the performance and economy to a motorcycle, not a car. 10%-20% is good if it is real, and should be looked into further, but it isn't the magical technology those numbers suggest at a glance.
Diesel will soon be gone for good, at least as we know it today. Exhaust limits.
About the thing, I have no way to know anything for sure, just guessing here. And why wouldn't that work, a C220 CDI already needs less than 5l in some optimal driving situations. That's not an impossible jump.
About the thing, I have no way to know anything for sure, just guessing here. And why wouldn't that work, a C220 CDI already needs less than 5l in some optimal driving situations. That's not an impossible jump.
Limits on what, out of interest? Particulates? SO2? CO2?
Old trucks are giving diesel an undeserved bad reputation.
All of those + NOx. We're already doing leaps and bounds to just satisfy the current norms (in normal cars, not trucks
).Aren't they using exhaust limits per gallon instead of per mile? So a SUV can score much better than a small diesel car?
Having just flown in and out of LA recently and seen the colour of the atmosphere
, I would say they need to do more.I dunno, I just know that the coleagues from the calibration team are always whining about CA and it's limits.
Just google for ULEV and SULEV, there you can see how things are developing in the US. We'll be getting EU5, I haven't looked into it yet but from what I heard it should be also rather tight.
Bring back the diesel particulates! (supposedly they reflect sunlight)
Releasing sulfate particulates high the atmosphere has been suggested as a possible quick and dirty fix for global warming, but the drawbacks are enormous.
Absorbing/reflecting more sunlight high in the atmosphere changes the heat distribution in the atmosphere and changes weather patterns, reduces evaporation of water from ground level(one of the suspected reasons for the Sahel monsoon failures of the 80's) and reduces plant growth.
ShootMyMonkey
Veteran
Seems like the bigger challenge then, is to counteract the problems borne of crappy quality diesel fuel, which is really the norm just about everywhere. Low-sulphur diesel and/or synthetic and/or biodiesel is often needed to meet the emissions standards of a lot of states throughout the US(save California which is practically a brick wall regarding diesel -- CA will probably reach the point where at least B50 biodiesel is the only kind allowable if that isn't the case already).All of those + NOx. We're already doing leaps and bounds to just satisfy the current norms (in normal cars, not trucks
If you actually have good quality fuel itself, a lot of those problems are very much diminished (though certainly not eliminated). NOx is probably the big exception to that, though. Urea injection is probably the cheapest solution, but I kind of agree with the EPA's objection to urea (namely that drivers are too absent-minded to fill two tanks regularly).
That is correct -- in fact, the example you bring up is most likely true in all cases. All US emissions standards are measured this way, and likewise, you'll frequently see turbocharged 6-cylinders show better emissions than an N/A 4-cylinder of half the displacement.
The problem with diesel is the particulates. Once you get rid of those you can install catalyst converters on diesel engines and vastly reduce carbon monoxide and NOx (ie. smog problems).
Are catalyst converters even standard in the U.S. ?
With the focus on CO2 emmisions I don't think diesel engines are going away , - quite the opposite.
Cheers
Are catalyst converters even standard in the U.S. ?
With the focus on CO2 emmisions I don't think diesel engines are going away , - quite the opposite.
Cheers
So, it doesn't matter how much you burn, as long as you do it reasonably efficiently and burn gasoline? I expect the US car industry has lobbied successfully for that.
ShootMyMonkey
Veteran
Catalytic converters are standard, and I believe that at least for gasoline-powered, the law requires it on every vehicle. A big difficulty with catalytic converters on diesels is sulphur poisoning, which is why a lot of diesel proponents are trying to push for biodiesel. Even without a converter, it still produces little to no CO and particulates... though NOx isn't that much lower, IIRC.
Well, Americans are kind of backwards on a lot of things. They don't measure fuel consumption (gal/n miles), but fuel economy(mpg). I don't know about you, but I've never heard of anyone who drives by the gallon. Similarly, the emissions standards aren't about the quantity of exhaust based on the distance traveled, but on the overall "air quality" and how many ppm of CO2 and NOx and particulates and so on that results from driving on some fixed schedule. As a general rule, though, when comparing lower consumption vehicles to higher consumption ones, the lower consumption ones will still win most of the time (but then SUVs have different standards than passenger cars, anyway). But when there is something about the higher consumption one that enables it to get a cleaner burn, for instance, then all bets are off. And of course, diesel does worse because it produces certain specific things in its exhaust as part of normal operation which the standards are particularly most stringent about.
One big problem with diesels in the eyes of car manufacturers is that diesels demand beefier parts, and that makes them more expensive to produce and at the same time, they last much longer. Which means people will hold onto the vehicle longer and put more miles on it without buying new. What most any auto manufacturer (not just American) would like is for the buyer to look at automobiles as a consumable good.