And so, for those 31,250 SDHC cards, I'm going to spend something like $2,343,750! Ouch... I'd rather lug the HDDs or the Blu-Rays. Or, maybe I'll wait for the 64GB SDXC cards... at 41kg, I could actually carry it. Of course, the price wouldn't be a good thing... let's 15,625 SDXC cards, and these things are going to be bigtime expensive for awhile.. probably over $3M. No thanks.
A petabyte is 1,0000,0000 gigabytes... you're thinking of a petabibyte. Same reason you only need 500 of the 2TB (2,000,000,000,000 byte) drives. I did the calculation before I found yours... the BD-R 50s weight less, but cost more than the WD HDDs; you could do it with 640KG worth of BD-R 25s, but it would cost a bit less than the WD drives. Well, at least at their prices... I just bought one of those at Dell for $200, but the on-line coupon was only good for one drive at that price.
That's about 16gm per disc, 50GB each, so you need 20,000 discs... but they total weight is only 320KG, beating the HDDs on weight if not necessarily volume. That's gonna run around $270,000, based on the best "cakebox" price I could quickly find online...goes to $380,000 if you need REs... the HDDs still win here. Going to BD-R 20s, you're going to about double the weight to 640KG with the 40,000 discs needed, but the price would drop to $112,000, also based on per unit prices of today's 50-disc cakeboxes at an online retailer. Obviously, you could get a better deal in this volume... but same goes for the WD drives.
Back in the mid-70s, I built my fourth and final electronic clock (one for each year of high school)... this one was designed to match my stereo system. And it included a relay, to turn on the stereo system (well, actually a quadraphonic system.. this was the 70s, after all), so that I could wake to full volume rock music. That thing is only slightly larger than one of my speakers!
Actually, the 2010 Prius (shipping since late May) is designed to operate as a plug-in hybrid. All belts are gone, electric pumps are there to pump anything that needs to be pumped when the engine is off.
Certainly, the current ones are not plug-ins, but they're currently starting trials on plug-in build, in rental and corporate fleets. http://www.wired.com/autopia/2009/06/plug-in-prius/ http://usnews.rankingsandreviews.com/cars-trucks/daily-news/090604-Toyota-to-Lease-Plug-in-Prius-/ http://technologyexpert.blogspot.com/2008/08/plug-in-prius-fleet-tests-moved-up-to.html
It's not a plug-in roll-out by any means.. they're testing it. This is a move to Li-ion batteries, which means the largest single change since the Prius was introduced in 1998 (1999 model year). Chevy is doing likewise with pre-production Volts. Both are expected to hit the market in 2011/2012 if things go well.
Actually, a parallel system is like Honda's -- the electric motor and ICE always run in parallel.
The Toyota system can behave as either a series or parallel hybrid system, depending on the interactions between the ICE, MG1, and MG2. One easy example... if you're in reverse, and there's not enough juice in the traction battery, the ICE and MG1 will kick on and generate electricity. They have to... the Prius has a permanent, fixed gear set.. there's no mechanical reverse gear.
You wouldn't ordinarily run into a series hybrid mode going forward... it's possible to do it, but the computer would likely opt to directly drive from the ICE, since that's more efficient than a series hybrid mode would be. The series mode would also be limited in speed, just like "stealth" mode (electric-only).
The MG1 motor/generator (the small one) acts as a motor in two conditions. One, as you state, is for starting the ICE... it revs up to 1000rpm, then kicks on the ICE, so it's an instant start with no wear and tear associated with typical ICE startup.
The other time is at higher speeds. When you're driving slowly, MG1 adds drag (by behaving as a generator) in the power split device (the planetary gearbox in which the ICE, MG1, and MG2 meet), effectively simulating a low gear. At higher speeds, MG1 acts as a motor, lowering the effective gear ratio and simulating a higher gear. When this happens, MG2 is dragging a small bit, to generate a small bit of electricity to power MG1 in this. On my 2003 Prius, this mode kicks in somewhere around 60mph.
The Prius is not really a series hybrid... or a parallel hybrid, it's both.
As some have mentioned, a series hybrid (Chevy Volt, diesel-electric train) powers the wheels from an electric motor. When it runs on fuel, the fuel drives a generator, which in turn provides electricity for the motor.
In a Prius, you can do that... the ICE can run, transfer mechanical power to the small electric motor/generator (MG1), generate electricity to the large electric motor/generator (MG2), which then moves the wheels. In fact, you have to run this way if you're in reverse and the traction battery isn't full... there's no gear shifting, thus, no direct-ICE driven reverse gear.
But going through the same simple gearbox (power split device), the ICE can directly drive the Prius final drivetrain... with or without MG2 kicking in. In that mode, it's acting as a parallel hybrid. You can see a Java-based simulator here: http://www.wind.sannet.ne.jp/m_matsu/prius/ThsSimu/index_i18n.html
No, the Fusion hybrid is larger than the Prius or the Insight. The 2010 model has an EPA rating of 41 city / 36 highway, versus the 2010 Prius rating of 51 city / 48 highway... both are based on the new tests that attempt to produce a more real-world rating for hybrid cars. The Fusion is equipped with a 2.5L Atkinson-Cycle ICE, versus the 1.8L Atkinson-Cycle ICE in the Prius, and I think it's got a slightly larger/heavier battery pack. The Fusion's hybrid system IS based on a license of Toyota's technology.
My 2003 Prius was rated 51 city / 45 highway under the old EPA system. I typically get around 45MPG in warm weather, mixed city, country, and highway driving. The best long trip (full tank) ever averaged at just under 52MPG, but that was not typical driving. In winter, I'm usually hovering just above 40MPG (a combination of winter fuel formulations, cold's effect on the battery, and the ICE being run more by the computer to keep things warm).
The new Insight gets a rating of 40 city / 43 highway. It's actually a bit smaller than the Prius, but it's using Honda's "mild" hybrid technology... this is a much smaller electric motor that's essentially acting as a booster to the small 1.3L ICE. You can't run in "stealth mode" (electric-only, ICE shut off) in a Honda. And you're stuck with a conventional transmission (they used to offer a dual-pulley CVT or a stick, not sure about the new version). One of the best things about the Toyota design: it's more reliable than a typical ICE car (no alternator, no starter, no transmission, and the engine is revved up to 1000rpm by one of the AC motors before ignition, so there's less wear on the engine this way).
Actually, GM's hybrid system is simpler than Toyota's... Toyota's is the first that can run as either a series or parallel hybrid system, which is exactly what you want for relatively small battery systems. It's extremely clever... no shifting, two electric motors and one ICE that meet at a set of fixed gears, yet allow either the ICE, the big motor, or both to drive the final drive of the car. The small motor adds drag or push in order to deliver the effect of a CVT, but without the problems (eg, weird pulleys and belts that break).
GM's is a pure series hybrid design... that's an electric car with an on-board gas powered charger, if you want to think about it that way. This is inherently less efficient than Toyota's design when you need the ICE, since the ICE can't directly drive the vehicle's wheel... it's permanently driving a generator, which in turn feeds power to the primary drive motor. I'm sure they optimize the ICE for this, but is only somewhat reasonable as a design given the relatively large battery in the vehicle. It remains to be seen what kind of mileage the Volt will get after the traction battery hits its 30%-charge minimum and the ICE has to kick in. They're saying "around 50MPG", but that's not yet a hard claim.
It may be good enough... I'm really going to be in the market for a plug-in hybrid, once my daughter claims my 2003 Prius in 2011 or so. The Volt is right in there... I have been following it was much as possible since they first spoke publicly about it. Even if they had to die and come back, it's good to see a US company getting serious about technology, not just silly marketing tricks. GM should have been here a decade ago... they could have produced something practical out of the EV1 experiment. Too many politics, at least at the old GM... it wouldn't suck if that was something lost in their re-invention.
The new 2010-model-year Mercedes E-class base model coupe (C207) delivers a Cd of 0.24, the sedan (W212) delivers a Cd of 0.25. The new 2010-model-year Prius (shipping since May) delivers a Cd of 0.25. Not much difference here, but sure, if you want bragging rights (assuming you have one of these, of course). The Mercedes looks to have more frontal area than a Prius, so I wouldn't expect better mileage based on this tiny difference (and the new high mileage, 4-cylinder versions get 44MPG according to Mercedes, but they may not show up on this side of the pond). The old Insight had a Cd of 0.25 since back in 1999 (with a tiny Cd x A of 5.10 ftÂ)... they decided to clone the look of the Prius for this year's all new model, but didn't get it quite right... they're all the way up there at 0.28. Typical passenger vehicles range up to about 0.45.. the Hummer H2 has a Cd of 0.57 (and a Cd x A of 26.3 ftÂ).
Why does the Mercedes look better than the Prius? Well, some of that's certainly personal taste. But I would suggest the rest of is it money: US$48,925 for the base model Mercedes versus $21,000 for the base model Prius. At more than twice the price, it had better look pretty. I think it may have to do my laundry and cook my dinner for me, too.
It shouldn't be surprising to note that many performance cars could have similar coefficients of drag... it's not usual for designers to increase this (some of those whale tails and other tail end aerodynamics) in order to decrease lift. It shouldn't be surprising either that, 10 years after the Prius first hit the streets, other companies might be thinking seriously about green car technology. Mercedes is one of them, and they're claiming they'll hit 0.20 within the five years.
I think they've been smart about it... $110K for a SuperCar (at least off the line, if not anything like top-end speed) isn't bad, so they were in the right kind of place with the Roadster. The Model S will be about half of that, and it's aimed at established luxery sedans... if it's close enough, they'll probably sell a bunch of these to rich Californians tied of squeezing into their Prius hybrids. The next one is supposed to use new battery technology and cut the price in half again.. that's more my speed.
I'm surprised it doesn't do better... the Prius is only about 32% efficient (the new ones.. and the numbers vary a bit...for my 2003, it was claimed to be 26%). That's of course based on the current state of well to pump efficiency being pretty high, and the ICE just sucking rocks on efficiency. I guess it's the opposite with the Tesla... well to plug is not so good, but battery (80%) and motor (90-95%) are great.
Given the great energy density of gasoline and the awful efficiency of gasoline engines (even Atkinson-cycle engines as in the Prius) versus the wonderful efficiency of multi-phase AC electric motors and the horrible energy density of batteries, the Tesla had better use less than half the energy per mile. Of course, this also explains why the Prius goes 500-600 miles on a tank, while the Tesla goes half that at best (and the Model S, half again).
That's conventional Li-ion chemistry for you, sure enough. Anyone with an iPhone and a few months left on their AT&T contract can sympathize.
Unfortunately, last news I have read claims they're using the laptop cells for the "S" as well: http://www.autobloggreen.com/2009/06/24/tesla-to-keep-laptop-cells-until-3rd-gen-car-new-roadster-sales/
It's also something like 42kWhr, 160mile range to start with... other battery packs available in time.
The Roadster's packs are based on off-the-shelf laptop cells... at least they were. That's 300-500 charges, depending on just where you draw the line (usually it's "dead" when it only holds 80% of the original charge)... quite a bit better than 200 charges, but still, that's an expensive replacement. Also, with standard Li-ion cells, you also have aging.. they don't last terribly long, even with light use... 3-5 years, that's about it. Most folks know this... particularly iPhone users, who are lucky if their Li-poly cells outlast their AT&T contracts.
But there are definitiely many new technologies in the lab now, and many have been Coming Real Soon Now for several years. GM's claiming the cells used in the Volt (CPI/LG Chem 16kWhr Li-Mn) will be good for about 4,500 charges... proof is yet to come, I rekon, but they did a big trial with new tech batteries from several vendors tested. They're also taking the usual NiMh hybrid route and only partially cycling the battery, using only 55% of the range... not practical in a BEV. The first pre-production Volts, with all the right stuff in the all the right places, came off the line a week or two ago, and they're no going out to prove it all works.
With all that said, on the subject of the Model S, this is the last I read on it: http://www.autobloggreen.com/2009/06/24/tesla-to-keep-laptop-cells-until-3rd-gen-car-new-roadster-sales/
Basically, they're sticking with the laptop cells, which means, replace the whole battery pack in about three years. Also, the stock Model S is supposed to have only a 42-kWh battery pack, which should deliver a 160-mile range (however they specifically measure it). They plan to offer optional, larger capacity packs as future options/add-ins.
In those days, just the battery pack cost around $30,000 to make. And it was expected to last about three years. That was one big problem.
The film wasn't bad, but there was plenty of religion and myth mixed in with the facts. I had been following this whole thing as it happened (though the press, the regular EE Times, IEEE, and other articles on various bits of technology, etc) and there were very good reasons for not bringing the EV-1 to production in 1996. The problem was that, after all they, they gave in to the FCEV people within GM or whatever, and pretty much just dropped the technology. People forget, this was a technical trial, it wasn't a product, yet. Technical trials are supposed to lead to products, but when they don't, they should lead back to the drawing board and, eventually, another technical trial. That's how you learn.
Unfortunately, GM wasn't a good environment for this in the late 90s, and it got worse in the 2000's. We've all seen the end result this year.
Actually, the EV-1 was long dead before GM bought the consumer division of AM General to make the Hummers. Within GM, it was the problems with batteries (the fully cycled NiMh batteries in the EV-1 were only expected to last about three years) as much as range (75-100 miles on a charge) that killed the project. There are lots of conspiracies, of course.. there's a film about it, too. I also understand there was a big push by the fuel cell people in GM to cancel the EV as a dead-end... thus funneling that money into FCEVs. That was stupid... any FCEV is probably a hybrid anyway, and definitely an EV... all of that tech would have been jump-started.
There was also the problem that, profitably sold, the EV-1s would have cost over $100,000 at the time. Keep in mind, Stanley Ovshinsky had only recently invented the NiMh cell (the first model of the EV-1 used lead-acid cells, and had a 35-50 mile range)... this was cutting edge stuff, and still very expensive.
Today, it's still the battery. So far, no one's got a commercial battery for these things yet... maybe Real Soon Now, lots of things are in the labs, but not just yet. Even the Chevy Volt is pushing hard on battery technology... their requirements are for about 10x the normal charge/discharge cycles versus the usual Li--ion/Li-poly cells (up to around 500... GM's claiming 4,500 for the Volt's cells). You can cheat on a hybrid... the Prius only cycles over 60% of the capacity of the cell, for example... not practical when you need to squeeze significant range out of it.
Only the turbulent component of drag goes up as the square of velocity. That's very dependent on vehicle aerodynamics. The laminar component is linear with velocity.
Most NiMh cells can be charged at C*4 (four times the rated capacity) without exploding, as long as they're thermally monitored. So, if you can provide enough current, that's a fastest-possible time of 15 minutes, whatever the capacity. Most Li-ions support less than half of that, which is just about what they're suggesting here.
Some of the new battery technologies are working to change this... new anode and cathode materials in the lab are promising Li-ion based cells that can fully charge in a few minutes, and survive thousands of charge/discharge cycles without much loss in capacity. None of that easily solved how in the world you'd get that much power into a full BEV battery, even if it's ok to do so. But that kind of long life is ultimately the thing that's needed to make BEVs practical. Without that, the secondary sticker shock, when everyone's 3-5 year old battery cars need new cells, will kill the market before it really catches on.
My 2003 Prius does. It only hold 11.7 gallons, but does pretty well on mileage:-) My record is actually just over 600 miles, but that was a very good day, and not at my usual highway speeds. I don't think most new cars get 500 miles, but in general, they're ranging farther than they once did. That's been a trend... in college, I had a 1961 Thunderbird... it did about 200 miles on a tank (10mpg and 20 gallons of tank).
The advantage of all-electric... I could do most of my driving on 100% renewable energy, since I'm getting 100% renewable electricity these days (in Jersey, you can choose your power source... I think that's spreading across the country, too). I keep a truck (Toyota Tacoma) for my tree farm work, and my wife has a newish Camry (about 350-400 miles on a tank of gas), so this would be totally practical.
In fact, I'm likely to replace the Prius with either an all-electric or a plug-in hybrid, depending on how things go with this new technology. The main concern I have with BEVs is that, when they're fully cycled, current battery technologies don't last that long. The Prius battery is only cycled over 40% of its capacity (60% in the 2004+ models), that's what keeps it going for a few hundred-thousand miles. There's been a great deal of lab work on micro/nano-engineering anode/cathode materials to prevent battery demise, but until that's proven in the field, the BEV is an expensive proposition. The current Tesla sports car, using off-the-shelf laptop batteries, has an expected battery life of 3-5 years, last I read.
Actually, that's the down-sized model... the original came out in 1970 or so, and while it wasn't any 70lbs monster, it was pretty substantial, at least 25-30lbs. I learned programming on one of these; it was some years before my Dad started bringing home the smaller version for my weekend hacking.
I taught myself to program on a machine of practically the same vintage. Starting in about '73, my Dad used to lug home a TI Silent 700, and a couple of rolls of thermal paper, for my computing needs every weekend (with timesharing on a CDC machine at Bell Labs, where he was a Department Head). I don't know about 70lbs, but it was a pretty substantial suitcase, probably a good 25-30 lbs or more. And it hooked right into a phone, but of course, you had to have a Bell Standard handset, not a touchtone... they wouldn't fit the suction cups. I think the first Silent 700 came out in around 1970...
A few years into this, he switched me over to a compact version of the Silent 700... much smaller body, with exposed "suction cups" on the top, rather than in the body as before. That was only around 15lbs, I would guess.
I'm quite happy with my Drobo, and it basically met all the requirements you mention, without the finicky nature of a traditional external RAID. The one downsize... like most external drives, it's too slow for some kinds of work. But it's a great place to keep all the stuff I want online, for daily backups, etc.
You do have to wait some time when you change drives... I replaced a 500GB drive with a 1.5TB drive a month or so ago, and it was a good 14+ hours before it had integrated that drive. Doing that swap on the other 500GB drive was pretty quick, though (now at 5TB total). That's about the only issue... what it's actually doing is occasionally a bit spooky.
When I first got the unit, I had a few small issues, and wrote back and forth with some of the engineers at Data Robotics. They definitely knew their stuff, and by the next software release, all was fixed. My only real complaint now is that FW800 under Windows XP is too buggy to use (TI chipset on ePCI... you'd think if anything would work, that would be it), so when I'm in Windows I'm usually stuck on USB to the Drobo.
Of course, they have new 8-slot unit with GigE/iSCSI out... just a bit pricey for me, but it's nice to see them doing well.
He's actually correct on point #2/3... he's just using confusing terminology. He's taking about a Filesystem-level RAID, like a Windows stripeset of mirror, under the banner of "Software RAID". And he's right... if your SATA controller dies, and you move those stripeset drives to another SATA controller, you can re-mount the partition.
You're correct on those points as related to a BIOS-level software RAID, which he's calling "host RAID".
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And so, for those 31,250 SDHC cards, I'm going to spend something like $2,343,750! Ouch... I'd rather lug the HDDs or the Blu-Rays. Or, maybe I'll wait for the 64GB SDXC cards... at 41kg, I could actually carry it. Of course, the price wouldn't be a good thing ... let's 15,625 SDXC cards, and these things are going to be bigtime expensive for awhile.. probably over $3M. No thanks.
A petabyte is 1,0000,0000 gigabytes... you're thinking of a petabibyte. Same reason you only need 500 of the 2TB (2,000,000,000,000 byte) drives. I did the calculation before I found yours... the BD-R 50s weight less, but cost more than the WD HDDs; you could do it with 640KG worth of BD-R 25s, but it would cost a bit less than the WD drives. Well, at least at their prices... I just bought one of those at Dell for $200, but the on-line coupon was only good for one drive at that price.
That's about 16gm per disc, 50GB each, so you need 20,000 discs... but they total weight is only 320KG, beating the HDDs on weight if not necessarily volume. That's gonna run around $270,000, based on the best "cakebox" price I could quickly find online...goes to $380,000 if you need REs... the HDDs still win here. Going to BD-R 20s, you're going to about double the weight to 640KG with the 40,000 discs needed, but the price would drop to $112,000, also based on per unit prices of today's 50-disc cakeboxes at an online retailer. Obviously, you could get a better deal in this volume... but same goes for the WD drives.
Back in the mid-70s, I built my fourth and final electronic clock (one for each year of high school)... this one was designed to match my stereo system. And it included a relay, to turn on the stereo system (well, actually a quadraphonic system.. this was the 70s, after all), so that I could wake to full volume rock music. That thing is only slightly larger than one of my speakers!
Actually, the 2010 Prius (shipping since late May) is designed to operate as a plug-in hybrid. All belts are gone, electric pumps are there to pump anything that needs to be pumped when the engine is off.
Certainly, the current ones are not plug-ins, but they're currently starting trials on plug-in build, in rental and corporate fleets.
http://www.wired.com/autopia/2009/06/plug-in-prius/
http://usnews.rankingsandreviews.com/cars-trucks/daily-news/090604-Toyota-to-Lease-Plug-in-Prius-/
http://technologyexpert.blogspot.com/2008/08/plug-in-prius-fleet-tests-moved-up-to.html
It's not a plug-in roll-out by any means.. they're testing it. This is a move to Li-ion batteries, which means the largest single change since the Prius was introduced in 1998 (1999 model year). Chevy is doing likewise with pre-production Volts. Both are expected to hit the market in 2011/2012 if things go well.
Actually, a parallel system is like Honda's -- the electric motor and ICE always run in parallel.
The Toyota system can behave as either a series or parallel hybrid system, depending on the interactions between the ICE, MG1, and MG2. One easy example... if you're in reverse, and there's not enough juice in the traction battery, the ICE and MG1 will kick on and generate electricity. They have to... the Prius has a permanent, fixed gear set.. there's no mechanical reverse gear.
You wouldn't ordinarily run into a series hybrid mode going forward... it's possible to do it, but the computer would likely opt to directly drive from the ICE, since that's more efficient than a series hybrid mode would be. The series mode would also be limited in speed, just like "stealth" mode (electric-only).
The MG1 motor/generator (the small one) acts as a motor in two conditions. One, as you state, is for starting the ICE... it revs up to 1000rpm, then kicks on the ICE, so it's an instant start with no wear and tear associated with typical ICE startup.
The other time is at higher speeds. When you're driving slowly, MG1 adds drag (by behaving as a generator) in the power split device (the planetary gearbox in which the ICE, MG1, and MG2 meet), effectively simulating a low gear. At higher speeds, MG1 acts as a motor, lowering the effective gear ratio and simulating a higher gear. When this happens, MG2 is dragging a small bit, to generate a small bit of electricity to power MG1 in this. On my 2003 Prius, this mode kicks in somewhere around 60mph.
The Prius is not really a series hybrid... or a parallel hybrid, it's both.
As some have mentioned, a series hybrid (Chevy Volt, diesel-electric train) powers the wheels from an electric motor. When it runs on fuel, the fuel drives a generator, which in turn provides electricity for the motor.
In a Prius, you can do that... the ICE can run, transfer mechanical power to the small electric motor/generator (MG1), generate electricity to the large electric motor/generator (MG2), which then moves the wheels. In fact, you have to run this way if you're in reverse and the traction battery isn't full... there's no gear shifting, thus, no direct-ICE driven reverse gear.
But going through the same simple gearbox (power split device), the ICE can directly drive the Prius final drivetrain... with or without MG2 kicking in. In that mode, it's acting as a parallel hybrid. You can see a Java-based simulator here:
http://www.wind.sannet.ne.jp/m_matsu/prius/ThsSimu/index_i18n.html
No, the Fusion hybrid is larger than the Prius or the Insight. The 2010 model has an EPA rating of 41 city / 36 highway, versus the 2010 Prius rating of 51 city / 48 highway... both are based on the new tests that attempt to produce a more real-world rating for hybrid cars. The Fusion is equipped with a 2.5L Atkinson-Cycle ICE, versus the 1.8L Atkinson-Cycle ICE in the Prius, and I think it's got a slightly larger/heavier battery pack. The Fusion's hybrid system IS based on a license of Toyota's technology.
My 2003 Prius was rated 51 city / 45 highway under the old EPA system. I typically get around 45MPG in warm weather, mixed city, country, and highway driving. The best long trip (full tank) ever averaged at just under 52MPG, but that was not typical driving. In winter, I'm usually hovering just above 40MPG (a combination of winter fuel formulations, cold's effect on the battery, and the ICE being run more by the computer to keep things warm).
The new Insight gets a rating of 40 city / 43 highway. It's actually a bit smaller than the Prius, but it's using Honda's "mild" hybrid technology... this is a much smaller electric motor that's essentially acting as a booster to the small 1.3L ICE. You can't run in "stealth mode" (electric-only, ICE shut off) in a Honda. And you're stuck with a conventional transmission (they used to offer a dual-pulley CVT or a stick, not sure about the new version). One of the best things about the Toyota design: it's more reliable than a typical ICE car (no alternator, no starter, no transmission, and the engine is revved up to 1000rpm by one of the AC motors before ignition, so there's less wear on the engine this way).
Actually, GM's hybrid system is simpler than Toyota's... Toyota's is the first that can run as either a series or parallel hybrid system, which is exactly what you want for relatively small battery systems. It's extremely clever... no shifting, two electric motors and one ICE that meet at a set of fixed gears, yet allow either the ICE, the big motor, or both to drive the final drive of the car. The small motor adds drag or push in order to deliver the effect of a CVT, but without the problems (eg, weird pulleys and belts that break).
GM's is a pure series hybrid design... that's an electric car with an on-board gas powered charger, if you want to think about it that way. This is inherently less efficient than Toyota's design when you need the ICE, since the ICE can't directly drive the vehicle's wheel... it's permanently driving a generator, which in turn feeds power to the primary drive motor. I'm sure they optimize the ICE for this, but is only somewhat reasonable as a design given the relatively large battery in the vehicle. It remains to be seen what kind of mileage the Volt will get after the traction battery hits its 30%-charge minimum and the ICE has to kick in. They're saying "around 50MPG", but that's not yet a hard claim.
It may be good enough... I'm really going to be in the market for a plug-in hybrid, once my daughter claims my 2003 Prius in 2011 or so. The Volt is right in there... I have been following it was much as possible since they first spoke publicly about it. Even if they had to die and come back, it's good to see a US company getting serious about technology, not just silly marketing tricks. GM should have been here a decade ago... they could have produced something practical out of the EV1 experiment. Too many politics, at least at the old GM... it wouldn't suck if that was something lost in their re-invention.
The new 2010-model-year Mercedes E-class base model coupe (C207) delivers a Cd of 0.24, the sedan (W212) delivers a Cd of 0.25. The new 2010-model-year Prius (shipping since May) delivers a Cd of 0.25. Not much difference here, but sure, if you want bragging rights (assuming you have one of these, of course). The Mercedes looks to have more frontal area than a Prius, so I wouldn't expect better mileage based on this tiny difference (and the new high mileage, 4-cylinder versions get 44MPG according to Mercedes, but they may not show up on this side of the pond). The old Insight had a Cd of 0.25 since back in 1999 (with a tiny Cd x A of 5.10 ftÂ)... they decided to clone the look of the Prius for this year's all new model, but didn't get it quite right... they're all the way up there at 0.28. Typical passenger vehicles range up to about 0.45.. the Hummer H2 has a Cd of 0.57 (and a Cd x A of 26.3 ftÂ).
Why does the Mercedes look better than the Prius? Well, some of that's certainly personal taste. But I would suggest the rest of is it money: US$48,925 for the base model Mercedes versus $21,000 for the base model Prius. At more than twice the price, it had better look pretty. I think it may have to do my laundry and cook my dinner for me, too.
It shouldn't be surprising to note that many performance cars could have similar coefficients of drag... it's not usual for designers to increase this (some of those whale tails and other tail end aerodynamics) in order to decrease lift. It shouldn't be surprising either that, 10 years after the Prius first hit the streets, other companies might be thinking seriously about green car technology. Mercedes is one of them, and they're claiming they'll hit 0.20 within the five years.
I think they've been smart about it... $110K for a SuperCar (at least off the line, if not anything like top-end speed) isn't bad, so they were in the right kind of place with the Roadster. The Model S will be about half of that, and it's aimed at established luxery sedans... if it's close enough, they'll probably sell a bunch of these to rich Californians tied of squeezing into their Prius hybrids. The next one is supposed to use new battery technology and cut the price in half again.. that's more my speed.
I'm surprised it doesn't do better... the Prius is only about 32% efficient (the new ones.. and the numbers vary a bit...for my 2003, it was claimed to be 26%). That's of course based on the current state of well to pump efficiency being pretty high, and the ICE just sucking rocks on efficiency. I guess it's the opposite with the Tesla... well to plug is not so good, but battery (80%) and motor (90-95%) are great.
Given the great energy density of gasoline and the awful efficiency of gasoline engines (even Atkinson-cycle engines as in the Prius) versus the wonderful efficiency of multi-phase AC electric motors and the horrible energy density of batteries, the Tesla had better use less than half the energy per mile. Of course, this also explains why the Prius goes 500-600 miles on a tank, while the Tesla goes half that at best (and the Model S, half again).
That's conventional Li-ion chemistry for you, sure enough. Anyone with an iPhone and a few months left on their AT&T contract can sympathize.
Unfortunately, last news I have read claims they're using the laptop cells for the "S" as well:
http://www.autobloggreen.com/2009/06/24/tesla-to-keep-laptop-cells-until-3rd-gen-car-new-roadster-sales/
It's also something like 42kWhr, 160mile range to start with... other battery packs available in time.
Tata bough Jaguar and Rover from Ford recently... so you can actually do that with "real" cars, now.
The Roadster's packs are based on off-the-shelf laptop cells... at least they were. That's 300-500 charges, depending on just where you draw the line (usually it's "dead" when it only holds 80% of the original charge)... quite a bit better than 200 charges, but still, that's an expensive replacement. Also, with standard Li-ion cells, you also have aging.. they don't last terribly long, even with light use... 3-5 years, that's about it. Most folks know this... particularly iPhone users, who are lucky if their Li-poly cells outlast their AT&T contracts.
But there are definitiely many new technologies in the lab now, and many have been Coming Real Soon Now for several years. GM's claiming the cells used in the Volt (CPI/LG Chem 16kWhr Li-Mn) will be good for about 4,500 charges... proof is yet to come, I rekon, but they did a big trial with new tech batteries from several vendors tested. They're also taking the usual NiMh hybrid route and only partially cycling the battery, using only 55% of the range... not practical in a BEV. The first pre-production Volts, with all the right stuff in the all the right places, came off the line a week or two ago, and they're no going out to prove it all works.
With all that said, on the subject of the Model S, this is the last I read on it:
http://www.autobloggreen.com/2009/06/24/tesla-to-keep-laptop-cells-until-3rd-gen-car-new-roadster-sales/
Basically, they're sticking with the laptop cells, which means, replace the whole battery pack in about three years. Also, the stock Model S is supposed to have only a 42-kWh battery pack, which should deliver a 160-mile range (however they specifically measure it). They plan to offer optional, larger capacity packs as future options/add-ins.
In those days, just the battery pack cost around $30,000 to make. And it was expected to last about three years. That was one big problem.
The film wasn't bad, but there was plenty of religion and myth mixed in with the facts. I had been following this whole thing as it happened (though the press, the regular EE Times, IEEE, and other articles on various bits of technology, etc) and there were very good reasons for not bringing the EV-1 to production in 1996. The problem was that, after all they, they gave in to the FCEV people within GM or whatever, and pretty much just dropped the technology. People forget, this was a technical trial, it wasn't a product, yet. Technical trials are supposed to lead to products, but when they don't, they should lead back to the drawing board and, eventually, another technical trial. That's how you learn.
Unfortunately, GM wasn't a good environment for this in the late 90s, and it got worse in the 2000's. We've all seen the end result this year.
Actually, the EV-1 was long dead before GM bought the consumer division of AM General to make the Hummers. Within GM, it was the problems with batteries (the fully cycled NiMh batteries in the EV-1 were only expected to last about three years) as much as range (75-100 miles on a charge) that killed the project. There are lots of conspiracies, of course.. there's a film about it, too. I also understand there was a big push by the fuel cell people in GM to cancel the EV as a dead-end... thus funneling that money into FCEVs. That was stupid... any FCEV is probably a hybrid anyway, and definitely an EV... all of that tech would have been jump-started.
There was also the problem that, profitably sold, the EV-1s would have cost over $100,000 at the time. Keep in mind, Stanley Ovshinsky had only recently invented the NiMh cell (the first model of the EV-1 used lead-acid cells, and had a 35-50 mile range)... this was cutting edge stuff, and still very expensive.
Today, it's still the battery. So far, no one's got a commercial battery for these things yet... maybe Real Soon Now, lots of things are in the labs, but not just yet. Even the Chevy Volt is pushing hard on battery technology... their requirements are for about 10x the normal charge/discharge cycles versus the usual Li--ion/Li-poly cells (up to around 500... GM's claiming 4,500 for the Volt's cells). You can cheat on a hybrid... the Prius only cycles over 60% of the capacity of the cell, for example... not practical when you need to squeeze significant range out of it.
Only the turbulent component of drag goes up as the square of velocity. That's very dependent on vehicle aerodynamics. The laminar component is linear with velocity.
Most NiMh cells can be charged at C*4 (four times the rated capacity) without exploding, as long as they're thermally monitored. So, if you can provide enough current, that's a fastest-possible time of 15 minutes, whatever the capacity. Most Li-ions support less than half of that, which is just about what they're suggesting here.
Some of the new battery technologies are working to change this... new anode and cathode materials in the lab are promising Li-ion based cells that can fully charge in a few minutes, and survive thousands of charge/discharge cycles without much loss in capacity. None of that easily solved how in the world you'd get that much power into a full BEV battery, even if it's ok to do so. But that kind of long life is ultimately the thing that's needed to make BEVs practical. Without that, the secondary sticker shock, when everyone's 3-5 year old battery cars need new cells, will kill the market before it really catches on.
My 2003 Prius does. It only hold 11.7 gallons, but does pretty well on mileage :-) My record is actually just over 600 miles, but that was a very good day, and not at my usual highway speeds. I don't think most new cars get 500 miles, but in general, they're ranging farther than they once did. That's been a trend... in college, I had a 1961 Thunderbird... it did about 200 miles on a tank (10mpg and 20 gallons of tank).
The advantage of all-electric... I could do most of my driving on 100% renewable energy, since I'm getting 100% renewable electricity these days (in Jersey, you can choose your power source... I think that's spreading across the country, too). I keep a truck (Toyota Tacoma) for my tree farm work, and my wife has a newish Camry (about 350-400 miles on a tank of gas), so this would be totally practical.
In fact, I'm likely to replace the Prius with either an all-electric or a plug-in hybrid, depending on how things go with this new technology. The main concern I have with BEVs is that, when they're fully cycled, current battery technologies don't last that long. The Prius battery is only cycled over 40% of its capacity (60% in the 2004+ models), that's what keeps it going for a few hundred-thousand miles. There's been a great deal of lab work on micro/nano-engineering anode/cathode materials to prevent battery demise, but until that's proven in the field, the BEV is an expensive proposition. The current Tesla sports car, using off-the-shelf laptop batteries, has an expected battery life of 3-5 years, last I read.
Actually, that's the down-sized model... the original came out in 1970 or so, and while it wasn't any 70lbs monster, it was pretty substantial, at least 25-30lbs. I learned programming on one of these; it was some years before my Dad started bringing home the smaller version for my weekend hacking.
I taught myself to program on a machine of practically the same vintage. Starting in about '73, my Dad used to lug home a TI Silent 700, and a couple of rolls of thermal paper, for my computing needs every weekend (with timesharing on a CDC machine at Bell Labs, where he was a Department Head). I don't know about 70lbs, but it was a pretty substantial suitcase, probably a good 25-30 lbs or more. And it hooked right into a phone, but of course, you had to have a Bell Standard handset, not a touchtone... they wouldn't fit the suction cups. I think the first Silent 700 came out in around 1970...
A few years into this, he switched me over to a compact version of the Silent 700... much smaller body, with exposed "suction cups" on the top, rather than in the body as before. That was only around 15lbs, I would guess.
I'm quite happy with my Drobo, and it basically met all the requirements you mention, without the finicky nature of a traditional external RAID. The one downsize... like most external drives, it's too slow for some kinds of work. But it's a great place to keep all the stuff I want online, for daily backups, etc.
You do have to wait some time when you change drives... I replaced a 500GB drive with a 1.5TB drive a month or so ago, and it was a good 14+ hours before it had integrated that drive. Doing that swap on the other 500GB drive was pretty quick, though (now at 5TB total). That's about the only issue... what it's actually doing is occasionally a bit spooky.
When I first got the unit, I had a few small issues, and wrote back and forth with some of the engineers at Data Robotics. They definitely knew their stuff, and by the next software release, all was fixed. My only real complaint now is that FW800 under Windows XP is too buggy to use (TI chipset on ePCI... you'd think if anything would work, that would be it), so when I'm in Windows I'm usually stuck on USB to the Drobo.
Of course, they have new 8-slot unit with GigE/iSCSI out... just a bit pricey for me, but it's nice to see them doing well.
He's actually correct on point #2/3... he's just using confusing terminology. He's taking about a Filesystem-level RAID, like a Windows stripeset of mirror, under the banner of "Software RAID". And he's right... if your SATA controller dies, and you move those stripeset drives to another SATA controller, you can re-mount the partition.
You're correct on those points as related to a BIOS-level software RAID, which he's calling "host RAID".