Kidding's only hurdle is clearing GMs dick, before he swings on it.
Electrics *already* have a bit of a hurdle. VW Golf et al lightfoots
already claim near-60 mpg, and I think I read somewhere of diesels getting
Even tho the 100 mpge's of all electrics sound iimpressive, if you do the $$
calcs, the savings is perty small over 70 mpg..
Sheeit, Ed, you been ig'ing my posts? That closet fagit Kidding ALREADY has
a 75+++ year ROI over my shitty li'l 40 mpg Fit... which is ackshooly a
great car -- assuming the unwashed asses out there don't require leather
seats.... Why assholes prefer to sweat on leather, Idk.... no pun
The main pro'leng with these high effic diesels is they are (apparently)
expensive to build, expensive to maintain, very expensive to fix. Proly not
as 'spensive to fix as the Volt, but still.....
Now, this article purports that the new diesels, by lowering compression
ratio, solve the above costs AND improve efficiency.... I doubt it.
If they've dropped the CR to 14 (from a max of 22, iiuc), why not drop it to
to 10? or 7?
They claim better mixing from the lowered CR, for better effic.... OK
But what about effic LOSSES from the lowered CR?
Increased effic from reduced engine weight?? PLease.... why not just
reduce the weight of the frame/body, instead, and keep the high
"Unfortunately, the fuel and air at top dead-centre are rarely mixed as
thoroughly as necessary for complete combustion. And because ignition takes
place in the presence of a surplus of oxygen (from the highly compressed
air), this incomplete combustion produces soot particles and smog-forming
nitrogen oxides-the curse of traditional diesel engines."
Incomplete combustion from surplus oxygen??? Dats not what Moi lerntid in
So, ahm not really disagreeing with the article, just questioning some of
the causal connections.
I hope these diesels DO deliver.... I just don't think the above are
thoroughly cogent explanations.
AND, the BIGGIE Q: What will the upfront banging of the consumer be??
Will my shitty li'l Fit hand these diesels a(nother) 50+ year ROI
Some time ago 2-stroke engines were being bandied about as the New
(poh-tential) Green Thing.
Long live the Kawasaki H3 750 2-stroke triple. If they put wings on dat
thing, it woulda taken off into the air.... lol
On Mon, 8 Jul 2013 22:06:41 -0400, "Existential Angst"
As I said, that's a non-technical article that tells you where the car
manufacturers are going with diesels. They're getting close to 50%
thermal efficiency. Another 20%, as the article claims is coming,
would put them up in the range of the very best combined-cycle
electric powerplant generators -- close to 60%.
As for the technical side, there really is only one place to get your
answers: the Society of Automotive Engineers. They have hundreds of
white papers on the subject. They cost a bundle, but the abstracts are
free, and you can get the bottom lines from them. Trying to figure it
out from chemistry and elementary physics won't do it. The dynamics of
those engines are very subtle.
On Tue, 9 Jul 2013 08:08:02 -0400, "Existential Angst"
That one threw me, and it's probably a mistake. HOWEVER -- and this is
where things get subtle -- a lean mixture first gets a little hot as
you start to lean it out, and then it gets COLD as you lean it out
further. Less fuel burning in a given volume of gas puts less heat
into the burning mixture. With spark ignition, you quickly reach a
point where it won't even ignite -- except with stratified-charge,
direct injection, designed to burn very lean mixtures. There are such
engines in the labs.
What I think is that they meant more *air*, not more oxygen. But I
don't know. I'd need to see an engineering report on it because I can
visualize a lean mixture that's burning too cold to get complete
combustion of some of the higher-flash-point components of the fuel.
I'm not about to assume anything. _The Economist_ is pretty good at
And before you dismiss reporters/writers/editors, I'll remind you that
I'm a reporter/writer/editor, and I check things like that out
carefully before publishing anything. d8-)
The question is whether hybridizing these diesels would produce enough
benefit to bother with the electrics at all. The Europeans seem to
think the answer is no. Remember, the gain for diesel hybrids is less
than half that of spark-ignition hybrids, as we discussed before.
I'd like to see some results from those Bosch/Citroen experiments with
diesel hybrids, but not enough to spend time looking for them.
I don't think it's the education as much as a traditional background
in journalism. I started as an editor for the only trade magazine in
history that won the National Magazine Award outright (American
Machinist, 1969). We took accuracy *very* seriously. At least three
editors read everything before it was published, and the first two
were responsible for checking facts.
And then I spent 6 years as a medical editor, where one mistake could
get an editor fired.
The crap on the Internet is not written by journalists. They may be
educated, but they have never absorbed the ethics and discipline of
the business. They all want to be pundits, where anything goes.
That was part of your OJT education. The chemistry profs told us that
college only prepared us to understand the lessons we would hear on
Watching big-name reporters interview politicians clearly reveals
which were popularly chosen as leaders. There isn't a single network
newsperson I'd vote onto the town's budget committee.
We see them here during the NH Primary debates. So far I've managed to
stay off camera by prompting the reporters to share their own opinions
and pretending to care what they think.
This last election the photographers seem to have switched from Banana
Republic beige to North Face black for their distinctive uniform. Or
maybe I don't see them often enough to keep up. All black or black +
jeans was the tribal costume for backstage personnel when I was in
I was just checking to see if you were awake.... lol
By "benefit", I'm assuming part of that is ROI.
As some of the banter here has shown, very little added cost over a base ice
40 mpg car (like, uh, my Fit) can be supported, even for 100 mpge -- to
Kidding's ignerint chagrin..
Heh, when GM drops the price for the Gen2 Volt by $10K, dumbfuckKidding
won't be able to give his volt away.... and I'm sure he had all kinds of
resale value built in to his bullshit ultra-low cost to own.... LOL
Heh, but I got a great idea: Kidding can keep his Volt as a quiet backup
generator for his barn.... which oughtta be quiet, for $40K.... iffin he
can figger out how to drop 350 V to center-tapped 220.... lol
On Tue, 9 Jul 2013 09:24:16 -0400, "Existential Angst"
No, I mean strictly in terms of fuel economy.
Of course, it depends on fuel prices. In Amsterdam right now, a US
gallon of gas costs $9.09.
And it depends somewhat on whether you value driving in something
other than a shitbox. <g> I drove my Focus out to Chicago last Fall. I
can tell the difference between that and my Sonata, which I usually
drive out there. I could put a value on it, if I had to.
If you're really serious about ROI, consider a moped. d8-)
OK, is this "thermal efficiency" the same as thermodynamic efficiency?
I find that hard to believe, and 50 + 20 = 70%, which seems impossible
thermodynamically. Certainly, I don't think there's anything like that
out on the road now.
I know a bunch of people worked on adiabatic Diesels some time ago,
and it seems a concept that ought to work. Recover all that heat in
the exhaust and use it to heat the intake air, then you can manage
with lower compression. Compressing the air requires energy, but
if you can extract it from (free) waste heat, you get a big benefit.
It's 50% plus 20% of that 50% = 60%. But they're not there yet. There
are some small diesels in the labs that approach or slightly surpass
50%. A few car-sized HCCI engines have gone well over 50%. The latest
automotive turbodiesels are doing between 40% and 45%; possibly one or
two percent more. And large, stationary diesels get up to 54%.
The theoretical Carnot efficiency of a diesel operating between 298K
and 1750K is 83%. The potential is higher than for any turbines,
including combined-cycle stationary electrical generators. They've
made some breakthroughs over the past few years and I expect to see
50% within a year or two, for engines available in passenger cars.
With alternative fuels and the aforementioned HCCI, lots of lab
engines are getting over 50% now.
It is exciting. I've never seen as much research activity on engines
as we have going on now. The SAE papers are flying like snowflakes,
and the researchers are trying every combination of fuels, ignition,
supercharging, and so on that you can think of.
The ones to watch, short term to long term, are diesel and
turbodiesel; homogeneous-charge, compression-ignition (HCCI);
combined-fuel (two or more fuels at once, or at different times in the
combustion cycle); and combinations of two or more of these things.
Meantime, we have Atkinson-cycle engines for hybrids and gasoline
spark-ignition with direct injection that still have more development
room left in them.
Diesels, particularly, are being re-thought from the ground up.
I think that SOFC is Solid Oxide Fuel Cell; this may be the chief
long-term danger to internal combustion engines. If they can get the
practical details worked out.
Yeah, practicality is the big roadblock for alternatives. That, and
limited availability of solar and wind power, plus a real distribution
difficulty for hydrogen. When you're getting your electricity from
conventional sources and your hydrogen is reformed natual gas, there
isn't a lot to encourage proliferation of alternative power sources.
Interesting. I've been waiting most of my lifetime for one of those
brilliant alternatives to make it out of the science pages of the
newspapers, and I'm getting old enough that it's been a very long
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