Water==hydrogen. And it seems there's about a liter of water per cubic meter. Which I think as 'plentiful'.
Where are you getting that from? They found about 100L (0.1 m^3) of water in the ejecta from a crater about 20m across and about 4m deep. That's a volume of about 1700 cubic meters if you assume a cone -- probably more in the real world. That means that water made up about 60 ppm of the ejecta. That's trace.
There's a lot of carbon on the Moon, but in the form of carbides, not carbon dioxide.
Yes, there are carbides on the moon... but only in about 200ppm quantities, evenly distributed across the surface. We require carbon in massive quantities for industry and agriculture. Nitrogen is in about 100ppm quantities.
Self-sustaining Lunar colony will probably look a bit like 'steampunk' novels. I.e. metal will be cheap, massive constructions will be easy (because of gravity), and there will be little complex automation.
Metal, too, requires the massive production chains of modern technology for self sufficiency. And yes, the chains do at points *require* automation. Name a metal and I'll start breaking down its dependency chains for you to give you an idea of what I mean (assuming this post doesn't scroll off my comments list before I get a reply...)
And it's not that unrealistic. Take for example the Biosphere 2 project, it didn't really required that much of advanced technology.
1) It failed. 2) It was not self-sustaining; it had no ability to repair things in the long-term, just the short term. 3) It could not expand.
Agriculture will be the most important application, because there won't be a life without it. The rest can be deferred until Moon colony can produce spaceships.
Not if you want to produce almost anything. Again, life on the moon requires extensive modern technology, and there are consumables and things that wear out. Esp. on the moon, with its electrostatic dust gunking up every joint. And modern technology has *huge* dependency supply chains.
1) You compared the *fuel* used in gasoline cars to *electricity* generated, not to the *fuel* used to generate that electricity. So generation losses were already factored into the equation, but gasoline losses were not. 2) Power plants are more efficient than cars. Even coal plants in the US average 32% efficient (higher in Europe). NG baseload plants average about 42%. And transmission losses are tiny (92.8% average efficiency).
It's the same reason why companies invested in fuel cells -- a long-term hail mary pass. Certainly li-air beats all of the techs mentioned (with the possible exception of digital quantum batteries) in terms of energy density. But it has huge challenges that may or may not be able to be met. Probably not. And yes, there is (or at least was) little patent coverage in that arena.
Also note that batteries aren't only about electric cars. This is IBM we're talking about here. Think laptops and cell phones: they're low power, efficiency and lifespan aren't as important, but energy density is. So there's a much more immediate application.
No. Bond energy released in combustion is not equivalent to tensile strength.
Let's be more specific. The energy released from burning graphite (basically equivalent to SWNTs in terms of bonding structure) is about 32.8 MJ/kg and 72.9 MJ/l. So that's energy density. By the calculations within the digital quantum battery paper, the SWNTs with a 10nm anode tip won't fail until the capacitor hits 62 GJ/m^3 (62 MJ/l). But there is another issue: they note that while they use 62GPa as the tensile strength for carbon nanotubes (the best nanotubes we've tested so far), the actual theoretical limit is about 300GPa. Most nanotubes we've produced have defects along their length.
Now, obviously, adding a whole bunch of other bulk materials to the battery lowers the battery's total energy density significantly. But the key point is that the energy stressing the CNT anode without breaking it can be notably higher than the energy released from burning said anode. Not even counting the mass of the oxygen for combustion.
Furthermore, this is energy released as electricity, not heat. This means ~4 times more work done than if it were delivered as heat. And it also means a more power-dense drivetrain, which is the *real* issue; a drivetrain that takes up less mass and volume means more mass and room for batteries.
The luxury of not having to fuel your car at home? It's a luxury *to* fill your car at home. So you, you know, never have to drive out of your way to a gas station in your daily life and stand outside (sometimes in very adverse weather) while you fumble for payment, filling, etc.
One of the many reasons we don't burn it in our cars;)
I often like to joke, when people boast about the sort of mileage they get in their diesel cars and don't seem to understand that diesel is a denser fuel than gasoline and has a lot more pollution emitted per gallon, that I could modify my car to burn a fine beryllium slurry and easily get over 100mpg, and wow, wouldn't that be an eco-car -- 100mpg, right?:)
Look, you're not going to get me to defend the Iraq war. It's indefensible;)
The money from the Iraq war would pay for 3.5 Apollo programs. But I'd rather it pay for, for example, half a dozen revolutionary next-gen launch system to get space access costs down by an order of magnitude -- metastable fuels, next-gen reusables, scramjets, and even exotic things like launch loops. Apollo-style programs are certainly glamorous, but they don't move us ahead. If we ever want to truly conquer space, we need way cheaper access to space.
Don't feel bad about not being familiar with the NNSI; it's sort of a wonkish topic.:) Lots of people make the mistake of applying the CPI or GDP deflator for estimating what older NASA projects would cost today. But the inflation rates aren't the same. The CPI and GDP deflator are based on a grab bag of random consumer products. Back in the 1960s, most consumer products were made in the US without all that much automation. Today, inflation and outsourcing are widespread, keeping prices down. But the same isn't true with NASA. NASA still builds parts in low volumes and still employs very expensive US labor. As a consequence, their inflation rate is a lot higher than the CPI and GDP deflator.
Not even close. For example, beryllium blows it away in both volumetric and gravimetric energy density (and hydrogen blows beryllium out of the water in gravimetric comparisons, but sucks at volumetric).
Hydrogen was included in TFA comparison.
Nice try at changing the subject away from the fact that you're quite simply wrong about gasoline being the most energy-dense or nearly most energy dense substance in the universe. It's not even close. If you really want to find the most energy dense chemicals, you need to look at metastable solids. Cubane and nitrogen rings, for example. And there are some theoretical ones that may be even higher, such as triplet helium. These things way, way outclass gasoline in terms of energy density.
Energy is still stored in the electrical field in matter. A quantum battery needs a lot of infrastructure to handle the forces, so at least 50% of the weight will be wasted. (compare to the weight of a clamp holding a spring.)
1) "Still"? Chemical batteries don't store energies in electrical fields. 2) You're trying to bond energy released in a chemical reaction with tensile strength. Tensile strength != energy. And no, they're not related. A beryllium cord has a *lot* less tensile strength than a carbon nanotube cord (orders of magnitude), but releases significantly more energy when it burns.
No, A small VW diesel has up to 40% efficiency.
"Up to" != "Average usage". Duh. Diesel cars average about 25% efficiency in typical mixed usage. Engines only get their peak efficiency within a narrow power band.
An elelctric car may have 90%, but you can only use 60% of the battery without damaging it in a few cycles, so overall, 2x is conservative.
Wrong on so many different levels.
1) Efficiency has nothing to do with pack capacity. You're equating the two. 90% *efficiency*. Versus 20% *efficiency*. 2) The Tesla Roadster uses over 90% of its pack's capacity. Most li-ion BEVs are in the 75-90% DoD range. Not 60%. The Volt uses 50%, but only because A) they're taking an extremely conservative approach, and B) it's a small-pack PHEV.
You are partially correct. A brushless electric motor can have very high intermittent power density. maybe 10x of a gas engine. It is only limited by cooling. For continous power its power density is the same as a gas engine.
First off, you're confusing DC and AC motors. All AC motors are brushless. Brushless is a category of DC motors. Secondly, no. The Tesla Roadster can do anything but track duty without a liquid cooling system. With a liquid system it could easily due track duty. And even with just air cooling, it beats the hell out of non-sports cars in sustained power output, despite having an engine much smaller than even non-sports-cars that run on gasoline. And furthermore, how important is track duty to the average person?
It is actually quite complicated to cool an electric motor.
No. You can buy motors with the cooling already in place.
Think 100kW power, and 10kW heat.
First off, 100kW power is something you'll only ever get during very high acceleration or extremely high speeds. Cruising power is more like 10kW, meaning 1kW heat. Secondly, since gasoline cars average about 20% net efficiency, 100kW of gasoline power output equals *80* kW of heat that you need to get rid of. It's much, much easier for the EV.
Find an electric motor that had higher energy density than a gas engine for continous output, and I will stand corrected, and learn something new.
The very one we're talking about. The Roadster's motor can do 2/3rds of its peak output as sustained. And peak output does 0-60 in under 4 seconds.
Note that the Roadster's motor is hardly the most power dense electric motor out there. Look at the PML Flightlink in-wheel motors used in the Lightning GT, for example. Each in-wheel motor is rated for 120kW peak and are.. well, the size of a wheel.
Hydrogen is not plentiful on the moon. Nor is carbon. Water *was* found on the moon recently, but if you compare the estimated volume of water with the volume of the plume, it was only in trace quantities.
Sorry, but production chains for modern parts do include computers.
Don't need much nitrogen and phosphorus? Nitric and phosphoric acid are among are most widely used industrial chemicals. Both elements are critical in large quantities for agriculture. I could give a list a mile long of important things they're used for.
Gasoline at 50MJ/kg is pretty much the most dense energy storage possible in this universe excluding nuclear energy.
Not even close. For example, beryllium blows it away in both volumetric and gravimetric energy density (and hydrogen blows beryllium out of the water in gravimetric comparisons, but sucks at volumetric). And comparing any of them to nuclear energy is laughable.
This is kind of a fundamental limit as to how much energy can be stored in *any* system using potential energy of the electric field of matter.
No, it isn't. Nor is beryllium. Energy doesn't even have to be stored in chemical bonds (see, for example, digital quantum batteries).
You may get 2x better efficiency in an electric motor,
Try 4x in typical driving conditions.
but I can not see how a battery can approach this value.
It doesn't need to. A motor the size of a watermelon propels the Tesla Roadster from 0-60 in under 4 seconds. In gasoline cars, the fuel is light and the engine is heavy. In EVs, the motor is light and the "fuel" (the battery pack) is heavy. It's a reversed paradigm. You have to compare the mass and volume of the engine + fuel to the mass and volume of motor + fuel. And with current battery tech, you'll find that EVs are about 1/4 to 1/3 of the way to matching gasoline cars. But batteries have increased nearly 5-fold in energy density the past 21 years, and show no signs of stopping.
The annual energy usage of automobiles is more than the current electricity usage in the US.
True but grossly misleading.:) The average car has a tank-to-wheel average efficiency in normal combined city/highway driving of about 20%. Your average li-ion electric vehicle has a plug-to-wheel average efficiency under the same conditions of about 85%.
The person who responded to you first is indeed correct. It's not about patents; you're mixing up this with the old EV1 debacle. The Roadster uses 18650-format cobalt/graphite li-ion cells, which are already in mass production. They did this for obvious reasons; when they started out, the phosphates and spinels that everyone else is now using weren't really available.
As for fire, which the previous person commented on, each cell is contained within its own can that's designed to isolate failures to just that cell. It's a pretty complex pack indeed. Future EVs won't have such a complex pack. It's doubtful that even the Model S will, even though it's still going to be based on cobalt tech (that's what Tesla has experience with, after all -- and despite all its downsides, it is quite energy dense)
If you're curious as to how the pack is structured, there are 11 "sheets", each one made of 9 "bricks", and each of those made of 69 cells. Each of the cells in a brick are wired in parallel. The failure of one, therefore, has relatively little impact on the performance of the brick. The bricks and sheets are wired in series. Each sheet monitors the performance of all of its bricks and does load balancing on them, as well as logging failures. It's a pretty impressive piece of engineering.
8 hour charge for how many miles? I don't know about you, but my daily commute isn't 600 miles.
It's level 1 or level 2 charging at home, and level 3 or higher for long trips. And that's what it's going to be for probably the next century. It doesn't make sense to do it any other way. You only need fast charges when you're taking long trips, so you need fast charging stations available on the road. Around home, you want slow charging, which is gentler on the batteries (and, not to mention, the grid), as well as being more efficient.
By the way, for those who are curious:
Level 1: ~110V, 20A or less. US standard: SAE J1772 or the ever-common NEMA 5-15 plug. Level 2: ~220V, 80A or less. US standard: SAE J1772. European standard: Mennekes, based on IEC 60309. Level 3: ~440V, up to "hundreds" of amps. No official standard, but the TESCO connector seems to be becoming dominant.
The most powerful EV charger I'm aware of is an 800kW charger created by Aerovironment for TARDEC. That's ~800V and ~1000A, if I recall correctly. It's about the size of four vending machines pushed together.
Yeah, really explosive. And those are cobalt-based cells, the kind that everyone worries about but which are not used in most EVs (just Tesla and Tesla-derivatives).
How much worse of an accident do you get than one in which you end up with an SUV sitting on top of your car and your battery pack fully bashed in?
Oh, and also, to help you "extrapolate" properly in the future:
* EV drivetrains are currently handmade in small volumes, so they're very expensive. Even a low-end AC drivetrain will cost you about $10k (say, a DMOC445, AC24LS, and a Manzanita Micro PFC charger). A good one like the AC-150 that the Roadster's drivetrain was originally based on will run you more like $25k.
* The Tesla Roadster's pack is very, very different from the Volt's, so it's not a good idea to compare the two. The Roadster's is a high capacity based on cobalt cells with a massive cooling system and a high DoD. The Volt's is low capacity based on manganese cells with a smaller cooling system and a low DoD.
* The Tesla Roadster is a luxury carbon fiber sports car that does 0-60 in under 4 seconds. You get what you pay for.
Well, for the record, GM says the Volt's pack costs under $10k. And that's first-generation. The raw materials in these types of cells are dirt cheap, so there's major potential for prices to drop in volume production.
The Prius depreciates a lot as soon as you drive it off the lot, but less than half as much each year after that -- despite being a more expensive vehicle.
Well, since the average driver drives about 12,000 miles a year, and the average car is on the road for nearly two decades....
Sure, an individual owner doesn't keep it that long, but what that means is that your depreciation will be lower, since the vehicle remains cheap to operate. Once the luxury of a luxury vehicle wears off, or the style of a stylish vehicle becomes dated, you don't have much left. But efficiency is always a seller. A Hummer doesn't cost that much more than a Prius, but it depreciates three times as fast.
Slashdot Mirror
Water==hydrogen. And it seems there's about a liter of water per cubic meter. Which I think as 'plentiful'.
Where are you getting that from? They found about 100L (0.1 m^3) of water in the ejecta from a crater about 20m across and about 4m deep. That's a volume of about 1700 cubic meters if you assume a cone -- probably more in the real world. That means that water made up about 60 ppm of the ejecta. That's trace.
There's a lot of carbon on the Moon, but in the form of carbides, not carbon dioxide.
Yes, there are carbides on the moon... but only in about 200ppm quantities, evenly distributed across the surface. We require carbon in massive quantities for industry and agriculture. Nitrogen is in about 100ppm quantities.
Self-sustaining Lunar colony will probably look a bit like 'steampunk' novels. I.e. metal will be cheap, massive constructions will be easy (because of gravity), and there will be little complex automation.
Metal, too, requires the massive production chains of modern technology for self sufficiency. And yes, the chains do at points *require* automation. Name a metal and I'll start breaking down its dependency chains for you to give you an idea of what I mean (assuming this post doesn't scroll off my comments list before I get a reply...)
And it's not that unrealistic. Take for example the Biosphere 2 project, it didn't really required that much of advanced technology.
1) It failed.
2) It was not self-sustaining; it had no ability to repair things in the long-term, just the short term.
3) It could not expand.
Agriculture will be the most important application, because there won't be a life without it. The rest can be deferred until Moon colony can produce spaceships.
Not if you want to produce almost anything. Again, life on the moon requires extensive modern technology, and there are consumables and things that wear out. Esp. on the moon, with its electrostatic dust gunking up every joint. And modern technology has *huge* dependency supply chains.
There are two problems with what you wrote.
1) You compared the *fuel* used in gasoline cars to *electricity* generated, not to the *fuel* used to generate that electricity. So generation losses were already factored into the equation, but gasoline losses were not.
2) Power plants are more efficient than cars. Even coal plants in the US average 32% efficient (higher in Europe). NG baseload plants average about 42%. And transmission losses are tiny (92.8% average efficiency).
It's the same reason why companies invested in fuel cells -- a long-term hail mary pass. Certainly li-air beats all of the techs mentioned (with the possible exception of digital quantum batteries) in terms of energy density. But it has huge challenges that may or may not be able to be met. Probably not. And yes, there is (or at least was) little patent coverage in that arena.
Also note that batteries aren't only about electric cars. This is IBM we're talking about here. Think laptops and cell phones: they're low power, efficiency and lifespan aren't as important, but energy density is. So there's a much more immediate application.
No. Bond energy released in combustion is not equivalent to tensile strength.
Let's be more specific. The energy released from burning graphite (basically equivalent to SWNTs in terms of bonding structure) is about 32.8 MJ/kg and 72.9 MJ/l. So that's energy density. By the calculations within the digital quantum battery paper, the SWNTs with a 10nm anode tip won't fail until the capacitor hits 62 GJ/m^3 (62 MJ/l). But there is another issue: they note that while they use 62GPa as the tensile strength for carbon nanotubes (the best nanotubes we've tested so far), the actual theoretical limit is about 300GPa. Most nanotubes we've produced have defects along their length.
Now, obviously, adding a whole bunch of other bulk materials to the battery lowers the battery's total energy density significantly. But the key point is that the energy stressing the CNT anode without breaking it can be notably higher than the energy released from burning said anode. Not even counting the mass of the oxygen for combustion.
Furthermore, this is energy released as electricity, not heat. This means ~4 times more work done than if it were delivered as heat. And it also means a more power-dense drivetrain, which is the *real* issue; a drivetrain that takes up less mass and volume means more mass and room for batteries.
The luxury of not having to fuel your car at home? It's a luxury *to* fill your car at home. So you, you know, never have to drive out of your way to a gas station in your daily life and stand outside (sometimes in very adverse weather) while you fumble for payment, filling, etc.
Indeed -- about half of the mpg gain is due to greater efficiency, and the other half is simply due to the higher density of the fuel.
One of the many reasons we don't burn it in our cars ;)
I often like to joke, when people boast about the sort of mileage they get in their diesel cars and don't seem to understand that diesel is a denser fuel than gasoline and has a lot more pollution emitted per gallon, that I could modify my car to burn a fine beryllium slurry and easily get over 100mpg, and wow, wouldn't that be an eco-car -- 100mpg, right? :)
Not all fuels are created equal. ;)
Look, you're not going to get me to defend the Iraq war. It's indefensible ;)
The money from the Iraq war would pay for 3.5 Apollo programs. But I'd rather it pay for, for example, half a dozen revolutionary next-gen launch system to get space access costs down by an order of magnitude -- metastable fuels, next-gen reusables, scramjets, and even exotic things like launch loops. Apollo-style programs are certainly glamorous, but they don't move us ahead. If we ever want to truly conquer space, we need way cheaper access to space.
Don't feel bad about not being familiar with the NNSI; it's sort of a wonkish topic. :) Lots of people make the mistake of applying the CPI or GDP deflator for estimating what older NASA projects would cost today. But the inflation rates aren't the same. The CPI and GDP deflator are based on a grab bag of random consumer products. Back in the 1960s, most consumer products were made in the US without all that much automation. Today, inflation and outsourcing are widespread, keeping prices down. But the same isn't true with NASA. NASA still builds parts in low volumes and still employs very expensive US labor. As a consequence, their inflation rate is a lot higher than the CPI and GDP deflator.
Not even close. For example, beryllium blows it away in both volumetric and gravimetric energy density (and hydrogen blows beryllium out of the water in gravimetric comparisons, but sucks at volumetric).
Hydrogen was included in TFA comparison.
Nice try at changing the subject away from the fact that you're quite simply wrong about gasoline being the most energy-dense or nearly most energy dense substance in the universe. It's not even close. If you really want to find the most energy dense chemicals, you need to look at metastable solids. Cubane and nitrogen rings, for example. And there are some theoretical ones that may be even higher, such as triplet helium. These things way, way outclass gasoline in terms of energy density.
Energy is still stored in the electrical field in matter. A quantum battery needs a lot of infrastructure to handle the forces, so at least 50% of the weight will be wasted. (compare to the weight of a clamp holding a spring.)
1) "Still"? Chemical batteries don't store energies in electrical fields.
2) You're trying to bond energy released in a chemical reaction with tensile strength. Tensile strength != energy. And no, they're not related. A beryllium cord has a *lot* less tensile strength than a carbon nanotube cord (orders of magnitude), but releases significantly more energy when it burns.
No, A small VW diesel has up to 40% efficiency.
"Up to" != "Average usage". Duh. Diesel cars average about 25% efficiency in typical mixed usage. Engines only get their peak efficiency within a narrow power band.
An elelctric car may have 90%, but you can only use 60% of the battery without damaging it in a few cycles, so overall, 2x is conservative.
Wrong on so many different levels.
1) Efficiency has nothing to do with pack capacity. You're equating the two. 90% *efficiency*. Versus 20% *efficiency*.
2) The Tesla Roadster uses over 90% of its pack's capacity. Most li-ion BEVs are in the 75-90% DoD range. Not 60%. The Volt uses 50%, but only because A) they're taking an extremely conservative approach, and B) it's a small-pack PHEV.
You are partially correct. A brushless electric motor can have very high intermittent power density. maybe 10x of a gas engine. It is only limited by cooling. For continous power its power density is the same as a gas engine.
First off, you're confusing DC and AC motors. All AC motors are brushless. Brushless is a category of DC motors. Secondly, no. The Tesla Roadster can do anything but track duty without a liquid cooling system. With a liquid system it could easily due track duty. And even with just air cooling, it beats the hell out of non-sports cars in sustained power output, despite having an engine much smaller than even non-sports-cars that run on gasoline. And furthermore, how important is track duty to the average person?
It is actually quite complicated to cool an electric motor.
No. You can buy motors with the cooling already in place.
Think 100kW power, and 10kW heat.
First off, 100kW power is something you'll only ever get during very high acceleration or extremely high speeds. Cruising power is more like 10kW, meaning 1kW heat. Secondly, since gasoline cars average about 20% net efficiency, 100kW of gasoline power output equals *80* kW of heat that you need to get rid of. It's much, much easier for the EV.
Find an electric motor that had higher energy density than a gas engine for continous output, and I will stand corrected, and learn something new.
The very one we're talking about. The Roadster's motor can do 2/3rds of its peak output as sustained. And peak output does 0-60 in under 4 seconds.
Note that the Roadster's motor is hardly the most power dense electric motor out there. Look at the PML Flightlink in-wheel motors used in the Lightning GT, for example. Each in-wheel motor is rated for 120kW peak and are.. well, the size of a wheel.
You never give your parrots showers? Poor birds!
My DYH amazon loves to be misted. :)
The *average* age of a car on the road today is 9.4 years and rising.
I did respond to it. What he wrote was complete pseudoscientific nonsense.
Let's pick another car. The Jetta TDI isn't as efficient as the Prius, and hence it doesn't score as well, but it still beats most cars.
It's all about operating costs.
Hydrogen is not plentiful on the moon. Nor is carbon. Water *was* found on the moon recently, but if you compare the estimated volume of water with the volume of the plume, it was only in trace quantities.
Sorry, but production chains for modern parts do include computers.
Don't need much nitrogen and phosphorus? Nitric and phosphoric acid are among are most widely used industrial chemicals. Both elements are critical in large quantities for agriculture. I could give a list a mile long of important things they're used for.
And you feel the need to charge at that rate *at home* why....? Do you have a 500 mile commute?
I only ever need rapid refill capability in my vehicle when taking trips, but perhaps your life is different.
Gasoline at 50MJ/kg is pretty much the most dense energy storage possible in this universe excluding nuclear energy.
Not even close. For example, beryllium blows it away in both volumetric and gravimetric energy density (and hydrogen blows beryllium out of the water in gravimetric comparisons, but sucks at volumetric). And comparing any of them to nuclear energy is laughable.
This is kind of a fundamental limit as to how much energy can be stored in *any* system using potential energy of the electric field of matter.
No, it isn't. Nor is beryllium. Energy doesn't even have to be stored in chemical bonds (see, for example, digital quantum batteries).
You may get 2x better efficiency in an electric motor,
Try 4x in typical driving conditions.
but I can not see how a battery can approach this value.
It doesn't need to. A motor the size of a watermelon propels the Tesla Roadster from 0-60 in under 4 seconds. In gasoline cars, the fuel is light and the engine is heavy. In EVs, the motor is light and the "fuel" (the battery pack) is heavy. It's a reversed paradigm. You have to compare the mass and volume of the engine + fuel to the mass and volume of motor + fuel. And with current battery tech, you'll find that EVs are about 1/4 to 1/3 of the way to matching gasoline cars. But batteries have increased nearly 5-fold in energy density the past 21 years, and show no signs of stopping.
The annual energy usage of automobiles is more than the current electricity usage in the US.
True but grossly misleading. :) The average car has a tank-to-wheel average efficiency in normal combined city/highway driving of about 20%. Your average li-ion electric vehicle has a plug-to-wheel average efficiency under the same conditions of about 85%.
The reality is that almost no new generating capacity is needed.
The person who responded to you first is indeed correct. It's not about patents; you're mixing up this with the old EV1 debacle. The Roadster uses 18650-format cobalt/graphite li-ion cells, which are already in mass production. They did this for obvious reasons; when they started out, the phosphates and spinels that everyone else is now using weren't really available.
As for fire, which the previous person commented on, each cell is contained within its own can that's designed to isolate failures to just that cell. It's a pretty complex pack indeed. Future EVs won't have such a complex pack. It's doubtful that even the Model S will, even though it's still going to be based on cobalt tech (that's what Tesla has experience with, after all -- and despite all its downsides, it is quite energy dense)
If you're curious as to how the pack is structured, there are 11 "sheets", each one made of 9 "bricks", and each of those made of 69 cells. Each of the cells in a brick are wired in parallel. The failure of one, therefore, has relatively little impact on the performance of the brick. The bricks and sheets are wired in series. Each sheet monitors the performance of all of its bricks and does load balancing on them, as well as logging failures. It's a pretty impressive piece of engineering.
8 hour charge for how many miles? I don't know about you, but my daily commute isn't 600 miles.
It's level 1 or level 2 charging at home, and level 3 or higher for long trips. And that's what it's going to be for probably the next century. It doesn't make sense to do it any other way. You only need fast charges when you're taking long trips, so you need fast charging stations available on the road. Around home, you want slow charging, which is gentler on the batteries (and, not to mention, the grid), as well as being more efficient.
By the way, for those who are curious:
Level 1: ~110V, 20A or less. US standard: SAE J1772 or the ever-common NEMA 5-15 plug.
Level 2: ~220V, 80A or less. US standard: SAE J1772. European standard: Mennekes, based on IEC 60309.
Level 3: ~440V, up to "hundreds" of amps. No official standard, but the TESCO connector seems to be becoming dominant.
The most powerful EV charger I'm aware of is an 800kW charger created by Aerovironment for TARDEC. That's ~800V and ~1000A, if I recall correctly. It's about the size of four vending machines pushed together.
Yeah, really explosive. And those are cobalt-based cells, the kind that everyone worries about but which are not used in most EVs (just Tesla and Tesla-derivatives).
How much worse of an accident do you get than one in which you end up with an SUV sitting on top of your car and your battery pack fully bashed in?
Oh, and also, to help you "extrapolate" properly in the future:
* EV drivetrains are currently handmade in small volumes, so they're very expensive. Even a low-end AC drivetrain will cost you about $10k (say, a DMOC445, AC24LS, and a Manzanita Micro PFC charger). A good one like the AC-150 that the Roadster's drivetrain was originally based on will run you more like $25k.
* The Tesla Roadster's pack is very, very different from the Volt's, so it's not a good idea to compare the two. The Roadster's is a high capacity based on cobalt cells with a massive cooling system and a high DoD. The Volt's is low capacity based on manganese cells with a smaller cooling system and a low DoD.
* The Tesla Roadster is a luxury carbon fiber sports car that does 0-60 in under 4 seconds. You get what you pay for.
Well, for the record, GM says the Volt's pack costs under $10k. And that's first-generation. The raw materials in these types of cells are dirt cheap, so there's major potential for prices to drop in volume production.
Accord. Prius.
The Prius depreciates a lot as soon as you drive it off the lot, but less than half as much each year after that -- despite being a more expensive vehicle.
Efficiency = low depreciation for the long run.
Um... huh?
Could you elaborate?
Well, since the average driver drives about 12,000 miles a year, and the average car is on the road for nearly two decades....
Sure, an individual owner doesn't keep it that long, but what that means is that your depreciation will be lower, since the vehicle remains cheap to operate. Once the luxury of a luxury vehicle wears off, or the style of a stylish vehicle becomes dated, you don't have much left. But efficiency is always a seller. A Hummer doesn't cost that much more than a Prius, but it depreciates three times as fast.