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Diesel Cars - High-Tech Low Tech
jonbrewer writes: "The NYTimes is running a great article talking about the growing trend of Diesel cars in Europe, their fantastic mileage, and the fact that America ignores them. While the article wows us with 78mpg for the Audi A2, I'm happy with the 45mpg my TDI Golf makes." Until diesel pumps are everywhere, I think I'll hold out for my solar/hydrogen-fuel-cell/flywheel hybrid.
I've been working on a project at Georgia Tech called FutureTruck, which is sponsored by the Department of Energy and some major automobile manufacturers. If you're interested, the website is here. GT is one of 15 schools from around the US and Canada that were tasked with taking a GM Suburban, a rather poor MPG performer but popular in today's market, and making it cleaner, more efficient, and (if possible) even more consumer-attractive.
;)
Just a couple things I've noticed over the past 2 years of this project:
1. Fuel cell vehicles are still a ways off. The hydrogen containers are bulky and heavy, and a system still costs around $1 million.
2. Diesel/biodiesel looks promising but a few problems remain - more polluting than normal gasoline, different performance issues, and such. However, they are more efficient overall. Paired with an electric motor, diesel engines could turn out to be cleaner and more effective than gasoline-only vehicles.
3. Electric-only vehicles are very limited in range and scope. Batteries are still heavy, even the 'new' kinds of batteries like Lithium-Ion. Combined with the need for a charging/recharging infrastructure, and the (at least) American desire for power, the electric-only vehicle will likely be relegated to shuttle cars on a set path.
4. Hybrids, like diesel-electric or gasoline-electric, seem to be the wave of the near future. I believe all the schools participating in FutureTruck are using a hybrid system of some sort. The Honda Insight is a good example of a production car that is a hybrid vehicle. It can reach about 70 MPG after a bit of driver training/getting-used-to. There are an array of configurations and methodologies for hybrid systems that I won't get into here, due to space considerations. But I believe, and so do a lot of other schools and even car manufacturers, that hybrids will pave the way in the near future. Beyond that... maybe they'll have fusion power worked out by then.
I hope this helps some of you out with what's going on in the alternative fuels/powertrain area. I am by no means an authority on this subject, so visit the Department of Energy, the Argonne National Laboratories, and the Society for Automotive Engineers websites for much more detailed information. Those websites are here, here, and here respectively.
Yeah, but they do it for a different reason, IIRC. Diesel locomotives use a hybrid arrangement because a pure diesel locomotive would have trouble moving away from rest smoothly (imagine changing gears on a locomotive . . . ). I don't know whether they use regenerative braking or not, though . . . as diesel locomotives tend to not brake very often it might not be worth it.
Go you big red fire engine!
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Of course, while petrol is as cheap as water in the US and Australia we'll all keep pouring fuel down our oversized, overpriced and unsafe (both for drivers, passengers and especially for other road users) SUVs. Sigh . . .
Go you big red fire engine!
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
...major improvements in electric engines.
One of the big bitches of electric cars is (besides battery life) the poor power/weight ratio of the electric engine against the gas (petrol) engine. Also, even more damning, is the relative reliability of the gas engine. What we really need are people putting alot more effort into making a better, lightweight electric engine.
We already have the parts to build a really good hybrid gas/electric car (which, face it folks, is the only kind of low-emissions vehicle you will see for years). We have the following parts:
The Honda Inspire and the coming competition from Nissan and Toyota are OK, but face it, we need something about the size of a Honda Accord, not a Honda Civic CRX. I can't see any reason (technically) right now why someone doesn't mass-produce a converted Accord. I mean, you can use the exact same design (maybe cheat and use alluminium body panels), just with a new powertrain (with an electric engine, you should probably have a continuously variable transmission, rather than an "automatic", and definately not a "standard") and still get at least 70+ miles/gallon (that is, 30km/l).
Hell, with the $4k US tax credit for buying a low-emission vehicle, and gas here at $1.75 in the DFW Area, I'd spend $5k more for a converted Accord over a normal one, and still make out like a bandit. So who're the morons in the Marketing Depts at the car manufacturers?
....in many European countries. It was a hot subject in the mid nineties, and heralded as a low pollution fuel** but the taxation in many places has increased to the point where diesel is now more expensive than petrol and thus mitigating some of the savings; fuel consumption differentials still ensure there's a chunk left though.
When diesel was hot, there was a move to increasingly high performance and larger diesels in small cars, thus eliding much of the economy value excpept on long trips - the Citroen ZX TD Volcane is a classic example - 1.9 turbo diesel, around 135 bhp in a small hatchback, makes 50 mpg* or so on the morotway but below 25 mpg* in traffic.
* Imperial gallons - US deduct 20% from those figures
** Ah yes, pollution - diesel produces a lot of unsightly smoke, but there is very little in the way of chemical pollutants, NOx etc in modern diesel exhaust. Diesel smoke is just that, smoke - it is much more environmentally friendly than the stuff you can't see that comes out of a petrol engine, cat or not - catalytic converters just don't work on short journeys. Ever smelled the (catalysed) car in front fart? That's hydrogen sulphide, and it isn't good for you.
Someone designed a wonderful system for dealing with the particulates from a diesel, which would involve placing a cotton wadding filter canister on the tailpipe - these would be washable and exchangeable at fuel stations, once per tank of fuel for a couple of dollars.
Another great thing is lean burn technology for petrol engines - great technology, no political will. There was so much political momentum behind the cat solution (not least because it came from America so must be cool) that superior alternatives got squashed.
I live in the aforesaid land of the free (Austin, TX to be exact) and yes, there is a long way to go in addressing pollution. OK, so they have cats here and people in Texas typically drive far enough for them to have an effect, but there's no emissions check whatsoever in what passes for an annual vehicle inspection in the lone star state. You can quite legally drive a 17 year old petrol Suburban (river barge disguised as a 4x4) that has the energy consumption of a small third world nation, blows more smoke than a badly tuned diesel under full load, and who knows what invisible noxious gases besides, and get away with it until the thing literally rusts apart.
The low fuel prices (petrol is literally half the price of bottled water, currently $1.35 to $1.70 per **gallon** depending on octane) and the local prediliction for having a huge-ass pickup truck as personal transportation don't exactly help - to set context for European readers, over here a Land Rover Discovery literally is a small, economical family car (and that's the 3.9 V8 petrol model, they don't even sell the diesel models).
Europeans just wouldn't understand - Texans really, truly do drive pickup trucks instead of cars, even if they rarely have a passenger and never haul a bigger load in them than a bag of grocery shopping; roughly half the *software dvelopers* in our company drive one (empty of course) to work every day. There is some concession to economy - almost none are 4 wheel drive, and a 3.8 V6 with a manual gearbox is more typical than the traditional 5.x V8 slush-o-matic, but moving a brick shape throuhg the air isn't cheap; 17 mpg US (21 mpg Imp) is considered *good*.
Until diesel pumps are everywhere, I think I'll hold out for my solar/hydrogen-fuel-cell/flywheel hybrid.
But diesel pumps are everywhere, at least near where I live (Toronto), where would many trucks get their fuel? Not many specialized diesel stations around. Almost always cheaper than regular gas, although a bit worse for the environment.
Here in the Bay Area a numbers of cities are running part of their fleets on diesel from recyled cooking oil - it's really wierd you go past one and it smells like fries :-) Apparently its low polluting and cheap, and the main drawback is that you need to replace all the rubber parts in your fuel system with synthetics and be carefull about changing your fuel filter more often
You can't compare a truck motor with the diesel motor that goes into a TDI Golf (or Passat, which I happen to have), especially when it comes to particle emissions.
One problem is very low temperatures. Below -20 Celcius, Diesel can "flock" which prevents the engine from running (even with gas mixed for cold protections you don't get much lower than -20 celcius). Countries like Canada would require some external heating for the motor during winter.
What is also relatively new is that the TDI Diesels get as much horsepower per engine-volume, of course coupled with a much higher torque. My 2.5 V6 TDI has 310Nm torque, which is more than the 2.9 gasoline Passat.
Micro carbon soot from diesel combustion in automobilies is a deadly carcinogeon and causes lung cancer. You know that lovely smell when a truck or bus drives by. Well, that's diesel. Diesel proponents say that magic "filters" can do the job, however, application of such filters reduces engine efficiency making such engines no more effiencent than gasoline. There are many new technologies on the horizon, including a high pressure combustion which works much like diesil but works with any hydrocarbon that are far better than diesel.
Someone you trust is one of us.
Check out the hemp car, a Mercedes Benz touring the U.S.A using hemp-based biodiesel. Hemp is such a great plant, it's a shame the D.E.A won't let us grow it!
Biodiesel could be the next great thing, outside of the US of course. Plus it helps out the farmers of this country that have been struggling to make ends meet.
It's time for the USA to take the lead in adopting new transportation technologies, and time to ditch the gasoline engine. Unfortunately, with the ExxonMobil Bush/Cheney team in command, it's gonna get worse before it gets any better.
~~+++ATH0 . . . END OF LINE