There's lot of news today about the latest attempt at a viable electric car. This one is called the Tesla Roadster:
tinyurl.com/m6v3l
tinyurl.com/hmokw
To summarise, it has a range of 250 miles (when new), does 0-60 in four seconds and can hit 130mph. It's made by Lotus (on behalf of the American company that invented it) here in the UK, in Norfolk. It will sell in the US for $100,000 a car. Obviously, costs could come down considerably if mass marketed.
Sounds great on paper doesn't it? They claim a life span of 125,000 miles before the batteries are worn out. Not so bad, eh?
However, when you do the maths it doesn't make any sense to me at all. The ultimate life of 125,000 miles is based on the typical 500 charge cycles multiplied by the 250 mile range, i.e. they have assumed you will always do the maximum range before re-charging, never a partial charge.
In the real world, this isn't going to happen, and in any case, isn't 500 charge cycles less than 2 years of daily use before the battery is worn out?
No doubt, like the lithium-ion batteries in mobiles phones and laptops, the battery range is likely to diminish over time, such that the actual range could be much less than 250 miles towards the end of the cars life.
Quote:
"Li-Ion batteries lose their capacity with every charge/discharge cycle. The slope is such that after about 100 charges the effective capacity is reduced to about 75%-85% of the original."
It doesn't even help if you don't use the car much:
"Li-Ion batteries stored for any time irreversibly lose capacity. The clock starts from the time the cell is made, and runs whether the battery is used or not. It loses approximately 10%/year."
From:
tinyurl.com/ms8fa
That's a loss of 25 miles a year on range, even without taking charge cycle degradation into account...
So, is it back to the drawing board, or has the internal combustion engine finally met its match? Is this technology likely to remain a play thing for the rich few or will it make it into our daily commute one day in the form of a Tesla Focus or a Tesla 3-series?
Opinions please...
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I think it's very cool, but as with all electric cars its environmental credentials depend entirely on how the electricity used to charge it is generated.
I bet it's great fun to drive though!
cheers
DP
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Well, we need to reduce our dependence on oil - or eliminate it altogether - as much for political and security reasons as ecological ones. This could be the way.
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True, but will a range of 250 miles that constantly decreases from when the battery is made and gets worse the more often you charge it be acceptable to Mr Average as a replacement for the ICE?
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Disposal of the batteries is a problem.
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TourVanMan TM < Ex RF >
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It's a cool car. Electric cars are generally a con as the sandal wearers don't want the pollution in their leafy suburb - they prefer it coming out of the power station where all the plebs live instead :-) Depending on how much energy is used in manufacture would show how environmentally friendly the car actually is. Until we have dust to dust comparisons of all cars then it is difficult to tell how green it is. Some info on the ABD site suggested a hummer was more environmentally friendly than a prius when you calculated the dust to dust costs of production and everything into its total environmental cost. I haven't read the full paper and I expect to find some strange assumption rendering it meaningless :-)
teabelly
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The characteristics of LiIon batteries are such that 4 quarter-discharge cycles use up roughly as much life as 1 full-discharge cycle. At least, that's the way I understand it from all the guides to maximising battery life on consumer gadgets I've seen.
As for the problems of disposal, I would suggest that disposing of 6000 cells from 1 car will be somewhat more straightforward than disposing of 6 cells from each of 1000 iPods, in that the economic viability and likelihood of recycling will be greatly enhanced by being in such bulk. Toyota certainly have recycling schemes in place already for their own hybrids, and offer something like a £150 bounty for returned packs.
Also, don't fall in to the trap of assuming that all batteries are particularly environmentally hazardous. The current technologies of NiMH and LiIon are not a significantly worse disposal problem from all the other horrible things found in a car. This is in contrast to their NiCad predecessors, or indeed the lead-acid battery in your own car.
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Fascinating thread for anyone worried about the long-term future of the privately owned automobile.
Obviously recycling is the key to battery-powered cars. The idea can be taken a step further, however. Power dealers - probably the present oil companies - could own all the batteries and lease them to motorists. Service stations could extract the used battery pack from the car and put in a newly recharged one. Perhaps the system could be refined, pace further improvements in battery technology, by the car having two battery packs to be used in sequence: when one runs out of juice the car carries on using the other until a fuel station is reached, when it can be replaced.
Same system as with bottled gas for yr country cottage gas cooker. Batteries will need to be smaller and lighter of course, and to maintain a positive full charge for many rechargings. Of course the battery monopolies will be able to find ways advantageous to themselves of ironing all these problems out.
I wouldn't be surprised if some of these things happened. Better than having no wheels (note lowercase).
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GM in the States offered electric cars to a retirement community as part of an advertizing campaign.These cars were supposed to have a range of 100-150 miles on a charge.However,there were complaints of batteries going flat after 40-50 miles and,on investigation,it was found that the drivers were making use of all the performance-ie. foot flat to the floor plus heater,a/c, and wipers.Years ago,it was stated that the i/c engine was on the way out because new battery technology would replace it with electric cars with longe range ability-we are still waiting for this technology.
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I still think the compressed air powered car is still the coolest option. Annoyingly it doesn't seem to be any nearer to production than when I first heard of it 5 years ago! That has a similar range but you can at least stop in any filling station and refill (albeit slowly) from the tyre pumps. You also gain free A/C with the air expansion, which is nice. Although not a great deal of use in the UK when you'd want to ideally save all the heat that went into the compression to stop you freezing to death in winter.
teabelly
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Yes Lud you have hit the nail on the head.
Its the support structure requirements that will make or break alternate fuels.
At the moment we have a support structure (refineries, pipelines, storage tanks, tanker network, filling stations) all using a common unified power source (petroleum products) to keep us mobile.
Hence my car will only 600 miles on its power source, before a recharge (filling up) but I KNOW i will be able to recharge anywhere, anytime.
If all cars had battery packs that were to a universal standard and fitting, could be whipped out and replaced fully charged in 5 minutes, lasted between 400 - 600 miles to the next charge RELIABLY, and I know it could be done anywhere any time then yes Battery power is just another convenient tank of gas.
This is your classic case of chicken and egg tho. The support structure players wont put it in place untill there is a large majority of cars using it, and the car makers wont make them till there is a support structure in place.
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TourVanMan TM < Ex RF >
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TVM / Lud,
That's exactly what we need, but the technology is nowhere near good enough yet for a reliable 300 mile range, never mind 600 miles. But the support infrastructure would soon develop if the cars were economically appealing or enough gov't incentive was applied. For instance, despite a relatively small number of users, there's still quite a few LPG pumps around, thanks to previous Powershift grants and discounted fuel duty.
Electric cars with complementing recharge/swap stations could happen, but not until the technology is good enough. If we try to create the infrastructure or incentivise the second-rate solutions, then it will backfire and put people off the electric car technology for good.
On the plus side, the existing filling station network is an excellent basis on which to build a battery swap/recharge support system.
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I don't particularly want to sit on a large tank of compressed air,hydrogen or a large lead/acid battery;gasoline is bad enough-diesel is probably safest.
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Check out the details in my post: the Tesla Roadster uses the same Li-Ion batteries that current mobiles and lap-tops use.
Mostly safe, although the much publicised Dell problems are a bit of a concern...
tinyurl.com/bxytk
If a laptop with a small Li-ion battery can explode in such a fashion as to cause real personal injury, what can the monster in the Tesla do?
Hmm, maybe you've got a point jc2!!
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Will the Tesla Roadser succeed? No - the 250 mile range will see to that.
At $100,000 the early adopters will buy for image, green conscience or curiosity alone, not value for money. But their enthusiasm won't last loing enough for the cost of production to fall if they're left stranded on the hard shoulder with a flat battery!
Will hybrids succeed, and through them, will battery technology develop enough to make an electric car viable? Yes - because your Prius won't leave you stranded in the meanwhile.
My best guess is that electric/fuel cell hybrids will be the technology most readily accecpted by the market. And for those of you who "don't particularly want to sit on a large tank of compressed air,hydrogen or a large lead/acid battery", I should add that hydrogen is safer than gasoline. A hydrogen leak disperses upwards to atmosphere, whereas liquid fuel forms a combustible puddle under the car.
(BTW, people often quote the Hindenburg disaster as proof that hydrogen is dangerous - but except for two crew working at the top of the balloon when it caught fire, all the deaths were caused by passengers jumping from the gondola. Those who followed the crew's instructions all escaped the crash.)
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One of the points that has been overlooked is the fact that this and similar cars are silent.
Having driven electric cars some years ago, including a Peugeot 106 example in France, I can vouch for the fact that it is very strange, but even more so for pedestrians.
Several times people were about to walk out in front of the car and then realised the possible danger.
I believe some companies introduced an artificial engine noise to overcome this problem.
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"but except for two crew working at the top of the balloon when it caught fire, all the deaths were caused by passengers jumping from the gondola. Those who followed the crew's instructions all escaped the crash."
them hot flame things looked fairly dangerous to me
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TourVanMan TM < Ex RF >
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come winter, what's the heater like?
JH
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Whatever the technology, it will still be taxed here.
Electricity delivered for driving use will be 55p per kwh compared to 8p per kwh for home use
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>>Whatever the technology, it will still be taxed here.>>
Energy is already taxed - just another lump sum for a certain Scottish gentleman.
Got two kids to look after now....
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What\'s for you won\'t pass you by
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