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Comment Re:They are a bit nutty.... (Score 2) 143

You're wrong there. The VW Up exists as both a pure electric and pure gasoline version. The difference in price? 10,000€

That's the price for the battery. In the case of the Up it almost doubles the price (from 12,000€ to 22,000€). And "all the other bits" being expensive? Seriously?

With the switch to pure electric you just god rid of the following: The alternator which provides the energy for all the gizmos in a normal gasoline car. And, more importantly, the transmission, one of the most complicated and intricate mechanical pieces in a car with a combustion engine.

Two complicated parts of the car, just poof! gone like that. The engine itself also just became way more easy - you don't need carefully timed pistons. You don't need the 3-way catalysator and the lambda probe. And so on and so forth. Hell, if you wanted to you could let each of the 4 wheels be driven by a separate motor! (which gets rid of the need for a differential!).

Comment Re:Expert?? (Score 2) 442

Yes. But they're not cheap and the production process is quite involved. And he specifically drew a relation between material used and possible aerodynamics:

[...]Replacing metals with ultralight, ultrastrong materials like carbon-fiber composites can provide safer, lighter and more aerodynamic vehicles that consume severalfold less energy and could be simpler to produce with 80% less capital.[...]

From:"Reinventing Fire: Three Energy Gamechangers for China and the World, Nov. 15th, 2013, pg. 2

He specifically mentioned "more aerodynamic" in addition to "lighter". I'm also not that convinced of "ultrastrong" materials being safer due to the fact that you want a crumple zone to soak up kinetic energy.

Not to mention that "severalfold less energy" is a lie: The BMW i3 already largely consists of carbon-fiber and is not that much lighter and, if you calculate the average energy consumption, doesn't consume that much less energy.

Lastly, carbon-fiber is not more "simpler to produce". Folding, bending and melting metals is easy compared to what you have to go through for carbon-fiber. Not to mention that it's not recycleable. Metal is easy to recycle.

Comment Re:"Dance" = rolling blackouts (Score 1) 442

Well, that's the problem with most renewable energy creators: They're dependent on an external factor. So, keeping some in "reserve" might not exactly yield the result you want. What use are additional windmills is there's no wind? What use are solar panels if it's nighttime or overcast?

Yes, there are others like biogas or waterpower, but most of those would fall under this heading of "energy storage" which this guy proposes to be superfluous. If they aren't storage technologies, they're usually not scalable enough, either due to provisioning problems (biogas) or geographical restrictions (water).

Comment Re:Expert?? (Score 2) 442

I did read some parts of it. For instance, he proposed that switching to carbon-fiber instead of metals that we would be able to create more aerodynamic shapes. Which is rubbish, of course, the shape of a car is not dependent on the material used.

He also proposed that switching to carbon-fiber would reduce costs. Far from it: Production of carbon-fiber is a very expensive process due to the way the shapes are formed. One of the reasons, by the way, why the BMW i3 is quite expensive.

There were a whole slew of conjectures, shoddy/dubious reasoning and exaggerations in there.

Comment Re:Expert?? (Score 3, Informative) 442

Well said. He also forgets that we already have problems with failover and unexpected losses of transmission lines which lead to blackouts.

I mean, one could probably design a system which works as he proposes - however, this would almost certainly mean a complete revamp of the existing electrical grid.

At which point investing in storage technology and facilities will be the cheaper and more reliable solution.

Comment Re:Books (Score 1) 421

I sincerely doubt that teaching matrices in 7th grade raises "understanding and awareness". As I said, I am a teacher and there's a reason why we don't begin with Maxwell's equations when talking about fields.
Again, difficulty of a subject does not automatically yield deeper understanding. You're making the same mistake as anyone who thinks that there's one way to teach: That there's one single way which works best.

There isn't. Teaching effectiveness depends on the pupil, the teacher, the subject, the classmates and a whole slew of other conditions.

And, to drive the point home: Simply raising the difficulty is a very bad way to go about it. Because you will lose the weaker pupils. You're obviously suffering from the notion that what was good for you must be good for others. I'm seeing this all the time: This notion of intellectual superiority just because you yourself mastered some difficult subject or other. Extrapolating from your subjective viewpoint to a general notion is a very big mistake.

Comment Re:Books (Score 1) 421

I have to say that you seem to make the mistake of regarding quantity equivalent to quality.

Take your bragging about how many books you had to read. I find it pretty hard to believe that you took anything meaningful from reading alot of quite difficult books. What's the use of reading so many books? And please don't try to tell me that you actually read and not merely skimmed them. I mean, we usually cover one book per month during lessons (if that much) but in detail.

Furthermore, matrices are indeed something you don't really need before university - I fail to see the use for that. That's coming from a Physics and Chemistry teacher, by the way.

And the Bavarian school system is moronic. They recently punished a teacher for having a class that was too good. They wanted her to grade her pupils on a bell curve. Again, "hard" is not the same as "good". And, yes, their results in tests like PISA are better (sometimes). But only because the sample groups are actually not comparable.

Comment Re:Books (Score 1) 421

Then you were going to the wrong school in Germany. There are quite a lot of "old-language" schools in Germany, I myself went to one of them. We could take latin in 7th grade and old greek in 9th grade (with french being an option in 11th grade).

Vacation time is 6 weeks in summer, 2 in autum, 2 in winter and 2 in spring.

Comment Re:This could be great (Score 3, Informative) 117

Oh, please. Creating explosives is easy (well, the creating part is easy. The "don't blow yourself up prematurely"-part usually not so much).

You merely need nitrating acid which you get by mixing nitric acid and sulfuric acid. Both acids are relatively easy to obtain (Both acids are sold on Amazon over here). Then you mix the nitrating acid with cotton, dry the stuff carefully and you got: Gunpowder Cotton, also called: Smokeless Gunpowder. All you need is a fumehood because mixing the acids is a bit hard on the lungs.

If you want to up the ante: Use glycerin (a laxative, also easily obtainable) instead of cotton. And, you guessed it: You get Nitroglycerin. However, the nitration process is exothermix and you need to be very careful when mixing the acid into the glycerin or it will blow up.

Those are just two examples. Almost the same process is used to produce TNT, by the way.

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