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Comment: Re:Pao Wants "Safe Spaces" for Shills and Ideologu (Score 1) 370 370

Humans are infamous for their groupthink in general. The Slashdot variety is actually pretty mild, if you have any baseline for comparison.

The telling thing is that people complain from all sides of various issues. For example, if you ask a libertarian, they'll tell you that Slashdot groupthink is liberal leaning socialist. If you ask a liberal, it's libertarian. But truth is, you see +5-modded comments from practically any perspective. About the only way to be consistently downmodded here without being a troll (or sufficiently troll-like in behavior, even if not deliberate, to make no difference) is to be a hardline creationist.

Comment: Re: FP! (Score 1) 587 587

You have no clue what you're talking about. The Wolfram page calculates torque given force and distance from a rotational axis, not rpm. I guess you've never turned a wrench in your life: when you have a long wrench on a stuck bolt, and it isn't moving, do you really think you're not exerting any torque on it?

Comment: Re: FP! (Score 1) 587 587

1) LOL, if you believe less energy is consumed at higher RPM in an electric motor, I've got perpetual motion machine to sell to you. A transmission allows you to operate the car at highway speeds at a much lower engine RPM.

Yes, you can get slightly decreased energy usage at lower rpms because of lower friction and less slip on an induction motor (the kind used by Tesla), but throwing a multispeed transmission in there adds weight and complexity, and also increases drivetrain losses (transmissions are inherently lossy), though the amount of loss over a single-speed gearbox is probably not much.

As I've asked before, what other applications have an electric motor paired with a multi-speed transmission? Train locomotives like these? Dump trucks like this one? Ship propulsion units like these? No, these all have motors either directly driving their loads, or using a single-speed reduction gear. And trains at least have a much higher typical speed range than cars do (0-150+mph for Acela Express, 0-220mph or more for high-speed trains outside the US).

Comment: Re:Hmmm... (Score 1) 81 81

Burning empty buildings and train tracks isn't "terrorism", it's "sabotage" and "arson". Messing up some train tracks to inconvenience people, and then calling it in so the train doesn't go over the tracks and no one gets hurt, isn't "terrorism", by definition, because there's no "terror" involved. This goes even more so for blowing up power lines, which rarely hurts anyone (unless it's in the middle of a heat wave or something, or cuts the power to a hospital).

This is like calling sit-in protesters "terrorists".

People taking their clothes off and marching to court? Are you kidding me? There's nothing remotely "terroristic" about that. That's a pure and simple protest. Protesting is not the same as terrorism.

Comment: Re: FP! (Score 4, Informative) 587 587

"Don't need" is highly debatable since even bicycles have gears for the sake of efficiency.

Bicycles are not powered by electric motors, and human legs do not resemble electric motors in any way at all. Human legs have a very limited speed range, just like gasoline engines; that's why transmissions exist.

Imagine driving your ICE car on the freeway in the 3rd gear -- that's going to cause a lot of engine wear and tear due to high engine RPM and drastically reduce mileage.

Electric motors are not like ICEs. Electric motors generate peak torque at stall (that's 0 rpm in case you didn't know). ICEs produce zero torque at stall, and don't even run that way, which is why they have clutches or torque converters, to allow them to idle. ICEs produce peak torque near the top of their speed range, completely the opposite of electric motors.

How many other applications can you think of where electric motors drive something through a transmission (I mean one with multiple gears, not a single-speed gearbox)? There are none. Train locomotives don't, ships don't, they all have direct-drive from their electric motors.

And if you're worried about speed, EVs don't run their motors slower, they run them faster than road speed, using a reduction gear. Go read your own link where that's mentioned. The Roadster only used a 2-speed transmission so they could get away with a smaller (lower torque, lower current) motor, but that really isn't a great idea because the complexity and weight of the transmission negates any cost, efficiency, or space gains you get from using a smaller motor. Higher speeds in an ICE are a problem because there's so many moving parts, and a bunch of them aren't rotating, they're reciprocating (think of the con-rods). This isn't the case in an electric motor, where there's only 1 moving part (aside from the balls in the bearings) and it rotates; higher speeds aren't much of a problem here, within reason.

Comment: Re:Dumb Design Choices (Score 2) 587 587

What sort of an idiot makes a car where the battery cannot be changed at a service station?

What sort of idiot thinks it'd be a great idea for someone to exchange their brand-new but discharged $20,000 battery for an old, worn-down battery that's been recharged at that station, and is now worth about $5,000 because it's near the end of its life, or worse, has bad cells and is on the brink of outright failure?

Whose bright idea was it to force consumers to plug their cars in for charging?

Maybe someone who realized people who commute every day would rather recharge at home, which takes no extra time at all, than waste time taking a separate trip to a service station?

Comment: Re:Gas, CO2, and heat pumps (Score 1) 587 587

I'm currently looking into replacing my gas furnace with a heat pump, powered by a combination of solar-, wind-, and hydro-generated electricity.

The negative is that my winter heating costs will double.

Maybe, maybe not; it entirely depends on the relative prices of electricity and gas in your area. I used to live in NJ and the natural gas prices there were atrocious; it would have been cheaper to heat the house with electricity (and in fact, that's what we ended up doing after we figured out how much gas heat was costing us: we turned the house heat way way down to just keep the pipes from freezing, and then used portable electric radiator-style heaters, because it was much cheaper that way).

Comment: Re:That pretty much sums it up (Score 1) 587 587

Chevy volt, nissan leaf, i3, etc are all pure POS in which the car sales have been going down, not up as expected. In general the leaf and i3 are too weird looking and offer equal or less performance to ICE cars BY DESIGN. Interestingly, all of the electric cars could EASILY blow away ICE cars. Why do they not? Because it would gut the sales of ICE so, none of the car companies want that.

This seems like BS, I'm sorry, at least if you're referring to range. On an EV, range is solely dictated by battery capacity. Batteries are expensive; they're easily the most-expensive component on a Tesla. If it weren't for the battery cost, we'd all be driving EVs now, because everything else on an EV is either the same or cheaper or not needed, compared to a gas car (brakes/steering/suspension: same; radiator/transmission: not needed; electric motor: cheaper than complicated ICE). Tesla's pushing down the battery costs, but it's taking a while. Unless I'm missing something, it simply isn't economically possible to build an EV under $30k with 200+ mile range, and it's all because of the batteries. Tesla has good range, but their car costs over $100k too.

You could be right about them being a top 5 carmaker within a decade, though, since they have a first-mover advantage, while the other carmakers have been doing little to nothing with EV technology. It's hard to say, though; it wouldn't be that hard for an existing company to jump on the bandwagon, since so many parts of a car are the same with EV propulsion (just not the engine). And IIRC Tesla gave out free access to their patented technology so that'll make it even easier.

Comment: Re:FP! (Score 1) 587 587

How long does it take to recharge to get that range back?

Not very long. You can plug the car in overnight at home so it's ready to go the next day for your daily commute, or you can go to a Supercharger station and recharge in 30 minutes. You do need to stop and use the bathroom and eat, don't you?

I take 2 or 3 trips a year touring

Simple answer: if stopping for 30 minutes at a Supercharger station is a problem for you, then rent a car for your rare trips. Or, use your other car. You do have two cars, don't you (assuming you're married/in a relationship)? Anyone rich enough to afford an EV of any kind, and who isn't single, has two cars in their family.

which gets about 200 miles per tank

What kind of shitty car do you have that only gets 200 miles per tank? Any decent car these days can go 3-400 miles per tank. If all you can afford is a 1975 AMC Gremlin, then no, an EV probably isn't in your budget.

Comment: Re:FP! (Score 1) 587 587

1) Range - short range compared to 250 or 300 miles of ICE cars.

My new Mazda has a range of over 400 miles. However, the Tesla Model S has a 200-250 mile range, so it's really not that far off. Of course, the Model S also costs over $100k for the one with that range.

2) Price - Why do EVs cost 2x or more compared to ICE cars when EVs have fewer amount of hardware components?

It's mostly in the batteries, and partly in the lack of competition. Tesla's the only really serious EV builder, and the other entries are kinda lame and some of them are just "compliance models", meant to appease government regulators and show them "look, we're trying to sell EVs, but no one wants them!"

If there were more automakers making serious EVs, and pushing the battery suppliers to do better, we'd see somewhat lower prices, and better progress in pushing prices down and performance (range, recharge time, etc.) up.

Comment: Re:The reason is more simple (Score 0) 587 587

Internal combustion folks (heh!) will NEVER ever like EVs. You can say EVs are three times more efficient, or that the byproducts are easily dealt with -- it doesn't matter. The guys have a Mechanical Engineering diploma... in their minds, fsck electricity!

Which is really ridiculous, considering how much electronics and software are involved in running modern ICEs.

Comment: Re:The reason is more simple (Score 4, Insightful) 587 587

According to a responder here, the Leaf's price is closer to $30k. And the Leaf is butt-ugly, and looks and drives like an econobox. A comparable gas car is probably about $15k, if not less. Crappy suspension and handling, cheap interior materials, lack of features; you're not getting much for your money that way.

That's the problem with EVs now; they're much more expensive than comparable gas cars. I've driven a Tesla Model S, and it's a great car, but it also cost $108,000. I just picked up a Mazda3 that has most of the features (including things like blind-spot warnings, lane-departure warnings, collision warning and automatic emergency braking, navigation, etc.) for under $30k, less than your Leaf, plus it gets over 35mpg (39mpg EPA hwy rating) and it has great power and excellent handling, maybe not quite sports-car level, but far better than a typical econobox.

When (if) Tesla comes out with their Model 3 in the mid-$30k price range, and if it has similar range to the Model S and still has good appointments compared to gas cars in that range, then we're going to see some real changes in the auto market. Electric cars are coming, it's just taking a while because of the battery cost.

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