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User: Rei

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  1. Re:That's it? on Progress On Electric Cars · · Score: 1

    How'd you arrive at that?

    Let's say the Aptera is a $15k premium over a traditional, 30mpg car, and let's assume no tax credits. $15000 / $5 = 3000 gallons = 90,000 miles = 7.5 years. With interest on the purchase premium, let's say 9 years. Throw in an extra year for the (uber-cheap) cost of electricity. The average car today lasts two decades, and with little steel to rust and lithium phosphate (very long-life) batteries, you should expect at least that. Let's say no difference in maintenance even though EVs have a small fraction as many moving parts to break -- meh, let's say that's because a battery pack replacement or something (even though a decade from now, battery packs will be a fraction of the price). The premium paid for your car pays itself off and then earns money for over half its lifespan. How's that not a winning proposition?

    It bugs me that most people don't look more than a few years ahead when planning their finances. Can you imagine if businesses took that same tack? No large factory would ever be built, no large mines ever developed, etc.

    (Oh, and if your argument is, "I won't keep my car until it dies; I change every several years"? Probably the biggest factor in determining the depreciation rate is how cheap it is to run. A Hummer costs 1.5 times as much as a Prius but depreciates 3 times as fast. And compared to even a 30mpg car, an Aptera is dirt cheap to run. So, expect a low depreciation rate.)

  2. Re:Here's what we need... on Progress On Electric Cars · · Score: 1

    Gas pumps don't work without power, either.

    If power's out at your home, then for those rare days, you need to go elsewhere to fill up. But again, that's the exception, not the rule.

  3. Re:That's it? on Progress On Electric Cars · · Score: 1

    100Wh/kg for batteries, 200Wh/mi for highway-speed consumption in a typical EV. You decide.

    Also, if there's any relevant percentage of EVs on the road, expect AAA and the like to start carrying high-power generators or battery packs around.

  4. Re:That's it? on Progress On Electric Cars · · Score: 4, Informative

    The most common number for the lower-cost EVs for range seems to be about 100 miles. About what percent of Americans do you think travel more than fifty miles to work and then 50 back? I'd bet under 10%. Probably under 5%.

    but don't kid yourself, anything approaching a 10% adoption rate of EVs could easily crush the grid

    This has been studied, over and over again. No, they don't. EVs are actually a rather sedate grid load in that they don't suddenly kick in, draw a huge amount of current, then stop; it's a steady load. And easily most of the time, it's a nighttime load, which is a boon for the grid, not a bane.

    But yes, our grid could use some overhaul because it's not good at dealing with our current loads. We need HVDC for long-distance transmission, a smart grid for timing loads, and EVs for variable loads and, potentially, V2G.

  5. Re:Soon, gas stations will be replaced by on Progress On Electric Cars · · Score: 2, Informative

    But I remember reading that conservation organizations are trying to shut down wind farms because of the damage they do to birds and (more recently) bats. Is this still the case?

    Even the Audubon Society supports Cape Wind. The "environmentalists" opposing these "controversial" wind farms are mostly just wealthy landowners who don't want the value of their homes to drop. The bird thing is largely a myth. Even taking into account the relatively small percent of our power that comes from wind, wind farms are just blips on the radar in terms of bird deaths in comparison to glass windows and housecats. The Audubon Society supports wind farms because pollution from fossil fuel power plants is a lot worse for birds than the very rare turbine-caused bird deaths.

    Although this seems astoundingly short -- I wonder what current would be required?)

    Depends on the size of your pack. On Oahu, they already have a network of AeroVironment Posicharge chargers, 60kW. Aerovironment makes them as big as ~250kW. As for generator capacity, the really big chargers use their own battery banks, which they trickle charge. And in the future, hopefully, will be able to smart charge and even feed power back.

  6. Re:Even coal is better than gasoline (no, really!) on Progress On Electric Cars · · Score: 1

    Actually, they are. One of the curious things about EVs is that the more power the drivetrain has, the *more* efficient they get. Just the opposite of gasoline cars.

  7. Re:That's it? on Progress On Electric Cars · · Score: 3, Interesting

    Yep. Batteries don't advance as fast as computers, but they've advanced a heck of a lot faster than anything in the transportation industry. In the past 15 years, battery energy densities have tripled, and power densities even more than that. And they show no signs of slowing down; check out the list of recent li-ion tech breakthroughs that promise 2-4 fold increases in energy density. The odds of every last breakthrough on that list failing to make it to commercialization seems vanishingly small.

  8. Re:Here's what we need... on Progress On Electric Cars · · Score: 2, Interesting

    I see it just the opposite. I, personally, am not fond of discovering that I have to go out of my way home from work to fill up with gas in the middle of a blizzard. I'd much rather just plug in each night and know that I never have to go out of my way to "fill up" except on long trips (i.e., the exceptions, not everyday life).

    I think the "500 km" requirement is not borne of anything actually related to driving, but simply is an artifact of "lets be like gas cars!" Gas cars need long range in order to cut down on how frequently you have to deal with the annoyance of having to fill up the tank in your everyday life. When it comes to long trips, the times you actually need range, you're supposed to get out and stretch every couple hours anyway. So so long as there's good enough infrastructure that there are frequent enough rapid charging stations (fast charging EV) / battery swap stations (battery-swapping EV) / gas stations (range extending trailer or PHEV), 150 miles range seems just peachy.

  9. Re:Wheee! 1,000 HP! on Progress On Electric Cars · · Score: 1

    You're thinking of gasoline engines. Electric drivetrains are highly efficient across their entire torque/RPM range. "Optimal" is generally something like a third of maximum torque and a third of maximum RPM, but even the worst case (which is usually high torque / very low RPM) is usually only like 70% or so efficiency. Not a huge difference between that and the peak of 90-95% efficiency or so.

    And actually, "over-sizing" electric drivetrains makes them *more* efficient. You have to use fatter cables to be able to handle the peak currents, which means that a given "cruising" current will encounter less resistance. The Tesla Roadster got something like 15 miles extra range when they upgraded to Powertrain 1.5 in order to compensate for removing the 2-gear transmission that kept breaking because there was too much torque.

  10. Re:Math on Progress On Electric Cars · · Score: 1

    A typical aerodynamic EV draws just over 200Wh/mi. A hyper-aerodynamic one like the Aptera can use much less, but let's ignore that for now and say 200Wh/mi * 200 mi = 40kWh. 40kWh / 235 (voltage drop) / 0.90 typical fast-charger efficiency * 6 = 1100 amps.

    And yes, some people are skeptical of this claim. It's not that delivering this sort of power is impossible -- far from it. Aerovironment's PosiCharge line goes up to the 250kW range -- that's the upper end of what's known as "L3" charging. But as far as I'm aware, that's normally done at higher voltages, with only a few hundred amps and a cooled cable. These sorts of powers sound extreme, and they are compared to what's in a typical wall outlet, but on the scheme of things, they're smaller than what goes into the switch at even a small industrial facility *24/7*. The only thing novel about this application (charging) is the requirement to be able to safely attach and detach this kind of current.

    Note that the only commercially-available batteries I'm aware of that could potentially meet these charging requirements are AltairNano's "nano-titanate" cells (a similar chemistry to Toshiba's SCiB). They could meet it easily, but they're super-expensive -- $2/Wh. Much cheaper are spinels and phosphates, but they're generally limited to 15-20 minutes for a full charge.

  11. Re:That's it? on Progress On Electric Cars · · Score: 1

    It actually gets worse. Clarkson is big into the hydrogen hype, and according to him, even if the drive had gone perfectly, he still would have consigned it to the dustbin because he feels electric cars are a dead end.

  12. Re:Soon, gas stations will be replaced by on Progress On Electric Cars · · Score: 1

    It's just over 50%. After coal comes nuclear and natural gas (near-zero emission and low emission, respectively), which are nearly tied at just under 20% each, then hydro at 6.5% (near-zero emission), then oil and renewables at about 3% each. However, two points:

    1) Renewables are very rapid growing. A third of the power that went onto our grid last year was wind alone. And that percent of renewables keeps rising, and is likely to rise even faster under the new administration.

    2) Power plants are more efficient than internal combustion engines, and only get more efficient over time. Transmission and charging losses for EVs are minimal -- 92.8% US average transmission losses and typically 92-93% efficient chargers, 96-99% efficient li-ion batteries. Electric drivetrains are ~85-90% efficient in typical operation. Oh, and EVs that charge at night, like most do, can reduce the amount of spinning standby (wasted power) and increase power generation efficiency (many generator types are inefficient at reduced capacity).

  13. Re:That's it? on Progress On Electric Cars · · Score: 1

    Aptera is voluntarily meeting most federal safety standards, and exceeding many by very wide margins. Yes, they get to pick and choose what makes the car safest and what's not important, but at least they're choosing to do so. The car was designed in parallel with aerodynamics and crash modelling software from Abaqus and CD-Adapco, both top notch. It has a full compliment of typical car safety features, long crumple/deflection zones, and one heck of a strong composite construction.

    Three wheels helps them get a vehicle to market faster and cheaper, that's quite true. But there are also a wide range of other benefits. Insurance is cheaper. The car can more easily follow the optimal teardrop shape. Reaction time to driver input is faster. Cost of construction is lower. Maintenance is lower. The car is lighter, and thus has less rolling drag. Lower rolling drag and lower aero drag means faster charging times and less power consumed. And so on down the line.

  14. Re:Aptera on Progress On Electric Cars · · Score: 2, Informative

    I haven't checked the site for a while, but all of their proposed plans had REAR wheel drive.

    The switch was made last January, but wasn't publicly announced until December. Switching to FWD gave a huge number of benefits, including much better regen, handling, and more room in the back.

    the plan was ~20k, but last I checked the total was closer to ~30k

    The plan hasn't been ~20k since mid 2007. You have been following them for a while! ;) When the Typ-1, Mk1 ("Zen") was unveiled in late '07, the announced prices were $27k for the Typ-1e and $30k for the Typ-1h. When they switched to the FWD 2e, they announced a price range of $25-$45k for the 2, depending on "options and drivetrain", and that there will be "a number of drivetrains" and "many options".

    I didn't like the plan for the windows to be static (immovable)

    Steve announced very early on that the windows *would* roll down in the final version.

    Unfortunately after a quick navigation of the website, I could not find the information I had once perused.

    Yeah, unfortunately, their site is in a bit of a transitional state right now. I'm not too impressed with Saxony Creative (who does their web work), personally.

  15. Re:That's it? on Progress On Electric Cars · · Score: 1

    Now, the info on safety is a little sparse from my quick look at Aptera's website, with the faq saying "It will match other commuter vehicles". Faq here. Safety Here

    The old version of the website was more detailed; it's kind of in transition right now. Yes, they have a full compliment of airbags, ABS, etc. Crash testing has been modelled by the same software BMW uses. It's a layered composite, like exotics (ever seen an exotic wrecked at 100+ mph, and the driver walks away? Composites are great that way). Here's a copy of an article whose author was introduced to the Aptera by its manufacturers handing them a sledgehammer and letting them wail on a shell. They nearly knocked their teeth out on the rebound and couldn't even scratch it. Roof and door crush strength have been reported to be over double the NTSB standard for cars.

    First up is the single back wheel. Won't that make the vehicle a rollover hazard?

    No. Here's excerpts from a great Road and Track article on the subject of three wheel stability. Net results of their testing of various delta (one-wheel forward), tadpole (one-wheel backward), and four-wheel vehicles? The deltas were always prone to oversteer and rollover, and no amount of tuning could change that. The tadpoles, like four-wheelers, were prone to understeer -- even a bit more than the four wheelers -- and were just as stable. Plus, they had a lower moment of inertia, and thus had a faster reaction time. When you think about it, it makes sense. When you brake, your CG shifts forward, putting it between the wide front stance. There's not much weight on the backside of a four-wheel vehicle when braking/turning.

    I presume the front wheels are extended to help mitigate this issue, but one good blowout looks like it could send that sucker fishtailing right into roll. (And for that matter, how servicable is that tire?)

    The panels on the side come off. Same with the front wheels.

    My second issue is the power-train. Generally you want as much weight sprung as possible, and electric motors are heavy. Aptera seems to understand that as it appears there is an axel linkage on the front wheels. Presumably this is how power is transmitted.

    Correct, except for the "electric motors are heavy" part. Electric motors are exceedingly light for how much power they produce. Batteries are heavy.

    Is having that axel exposed going to cause any safety and reliability issues?

    Driveshafts are typically exposed on the underside of a 4WD vehicle, right where rocks are getting kicked at them. Anyway, if there was any problem, they'd just shroud it.

    Could'nt the steering be accomplished by swiveling independent pods rather than linking them?

    The pods do swivel. The entire front of the car doesn't turn at once. There are CV joints at the wheels.

    It should also be noted that it's been reported that the batteries are mounted low, as is the passenger seating, so your CG is low. Anyone who's not familiar of the gains of mounting batteries low should take a look at videos of a Commuter Cars Tango ;) Tall, narrow little vehicle, looks like the most unstable thing in the world, yet it barely budges side to side on turns.

  16. Even coal is better than gasoline (no, really!) on Progress On Electric Cars · · Score: 5, Informative

    According to a DOE study conducted at PNL, switching to EVs is a net win even on our current grid. The main reason is that power plants are a lot more efficient than gasoline-powered cars at turning fuel into energy, while transmission and charging are very efficient. Also, EVs, which mainly charge at night, reduce the need for spinning standby, allow plants to operate more efficiently at night, and so on. The net result is that you could switch 84% of our cars over on our existing grid and you'd cut CO2 emissions by a third, increase PM somewhat, NOx would drop slightly, SOx would stay the same, and CO and VOCs would be nearly eliminated. The pollutants that would be emitted would be emitted on average much further from people's lungs and so affect them less.

  17. Big list on Progress On Electric Cars · · Score: 4, Informative

    I've compiled a big list of upcoming EVs and their stats here.

  18. Re:Tell me, where is Obama's name on Obama Sides With Bush In Spy Case · · Score: 1

    Didn't notice that, but that's simply because the administration changed, so the case name changed. It's still Bush administration people running the DOJ, and will be for weeks. Possibly months, depending on how much the Republicans can stall.

  19. Re:So much for not sacrificing ideals for safety. on Obama Sides With Bush In Spy Case · · Score: 1

    And it's myths like this that have led to disastrous economic policies for so many.

    No, They Do Not. You've obviously never known anyone who's poor. And it's actually a rather insulting suggestion to pretend that they do.

  20. Re:So much for not sacrificing ideals for safety. on Obama Sides With Bush In Spy Case · · Score: 1

    Americans will drop $5k on a 60" hdtv, but don't want to spend a dime on doctor bills to have a baby. WTF?

    Those aren't the Americans we're talking about. It never ceases to amaze me how distant so many people are from the economic reality of many tens of millions of Americans. The lowest quintile in the US has a household income of under $20k. $4k is a fifth of their entire combined annual household income. Pretax.

  21. Re:So much for not sacrificing ideals for safety. on Obama Sides With Bush In Spy Case · · Score: 5, Insightful

    Oh come on, it took an entire 3 days for a Deputy Assistant Attorney General under Alberto Gonzales who is acting Attorney General until Obama's pick is confirmed step on that promise, I think he's doing better than bush already!

    Corrected that for you.

  22. Tell me, where is Obama's name on Obama Sides With Bush In Spy Case · · Score: 5, Informative

    in this document? Does that look like his Attorney General's name to you? No, that's Deputy Assistant Attorney General Michael F. Hertz, who served under Alberto Gonzales; Obama's AG hasn't been confirmed yet.

    The US government didn't magically transform itself at the stroke of noon on Tuesday.

  23. Same as the old boss... *literally*. on Obama Sides With Bush In Spy Case · · Score: 5, Interesting

    Didn't it occur to anyone here that Obama's attorney general pick hasn't even been confirmed yet? Obama is only nominally in charge of the DOJ at this point. So who do you think it is filing these papers? Well, the names are right in the PDF, starting with Michael F. Hertz. Yes, Michael F. Hertz, Deputy Assistant Attorney General under Alberto Gonzales.

  24. Re:Remind me again... on Ink Breakthrough Heralds Bendy PC Screens · · Score: 2, Insightful

    Why, exactly, do we need bendy computer screens?

    You got the... the light... from the console... keep you... lift you up. They shine like... ... little angels...

  25. Re:What? on Obama Edicts Boost FOIA and .gov Websites · · Score: 1

    Only within the context of whether photos of atrocities should be destroyed or preserved.