Not so long ago here, there were lots of people that loved to talk about their vehicles and their nuiances, how to get the most fuel economy. Discussions were based on actual driving experiences with vehicles they have. It was people doing things. Actions are more valid than polictical rants and endless arguements on serial hybrid availablity, or for that matter it could be plug-in hybrids or fuel cell vehicles. (not that I object to rational discussions of those...)

I suppose "the next level" is encouraging people to join as total strangers for the pleasure of argruments. I must have missed the point by getting a hybrid instead of agitating.

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

I can well understand that there are those such as yourself, whose interest in hybrids is strictly the pragmatic business of your own personal vehicles and their merits, maintenance and performance. I have no problem with that, but if that is your interest, then I would suggest you have no purpose to be on this thread, and no purpose to be on this particular forum topic, there are forums dedicated to your particular interest.
If I did own a hybrid, I might well be interested in the same, but I don't and I'm not.

My interest is in the EV/hybrid technology, just as I'm interested in Nuclear Reactor design, Nuclear Fusion Technology and other Energy Production & Distribution issues - so according to you, If I don't happen to own one of those - there is no point to my interest. The world of science and technology would be awfully boring if everyone had your attitude.
I also happen to be interested in the politics behind the suppression of EV technology - and any logical argument must conclude that this is the most important of all EV/hybrid issues at this time. It has world shaking ramifications and could conceivably be the difference between our survival or the collapse of western civilization.

Your obvious sensitivity on this is surprising. I would be tempted to conclude that you are a pro-Bush conservative, who is finally realizing that he is not "The Moral Right" President you thought he was, instead you are beginning to see that he is a servant to Oil Interests, he invaded Iraq for their benefit, created this obvious disaster (as a CIA report has just confirmed) and if that isn't bad enough he is cooperating with their devious and utterly Immoral efforts to suppress EV technology.

Over here in Europe we had one for a while, it was a battery electric Renault Kangoo van, with a tiny gasoline (or natural gas) range extender engine to get you places when the 50 mile battery had run out.

Sadly, I think it is no longer sold though....

http://mysite.wanadoo-members.co.uk/ecotech/ecot.htm

Must be a very dry sense of humor - numerous times I've had unflattering things to say about the current administration's energy policies. Not one post that could be construed as an endorcement. People familiar with my posts know I echew politics unrelated to green issues - it gets exciting enough being on-topic. For general politics, you might want to check out Volconvo Debate Forums

Talk being superior to action is strange logic. Al Gore at the end of his movie An Inconvient Truth was making a call to action... it influenced the green laws Gov Schwartzenegger just signed...

I know if the average US vehicle got 40mpg it would not only be bigger green effect than all the rhetoric in the world, but it would seriously prompt the Bush administration and politicians of every stripe to do something. That's not something to dismiss.

Moving right along....

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

So, you didn't know the battery technology.
I can't find any specification about the capacitors at Telsa's site. It should be listed if it supplies a certain amount of energy.
Please let us know how much power and how long the Telsa's capacitors can supply.
Our discussion was not such things, it is enough no not.
The point was reducing the battery weight 110kg/280kg means we lose 60% of battery power based on W/kg specification.

Ken@Japan

I've never seen that particular spec on a battery, at least in that way, usually manufacturers instead list a maximum rec'd current drain on a specific battery (along with a variety of other specs), using a W/Kg listing is unusual but in someways a better method.
All PEM's/PWM's have capacitors on the DC bus, what rating the Tesla's have I don't know. But since they have a large battery bank, being a BEV rather than an HEV, it would not be necessary to store regenerative braking energy in capacitors, but can be dumped into the batteries. To optimize an HEV's design, more efficiency can be obtained by using ultra-capacitors on the DC bus as the primary energy storage device - that is for regenerative braking energy for which 1 kwh would be more than sufficient. This way the generator would charge the DC bus directly almost always bypasses the battery pack and thus its energy would be supplied without the 86% charging efficiency factor, reducing overall efficiency. The battery pack would then charge the capacitor bank when needed (and vice-versa) through a DC to DC convertor. This technology would also improve the efficiency of the parallel hybrid. The Prius captures some of the braking energy (up to .3 kwh) and stores it instead in a much larger battery bank of 1.2 kwh, or else the battery bank would have a short life expectancy due to the rapid cycling of the battery.
Yes, that is correct. But as I pointed out that still leaves more than ample battery power to drive the Tesla's electric motor at max power that the battery pack would need to provide.

It seems you don't understand the Tesla too.
http://www.teslamotors.com/
They never mentioned such ultra-capacitors nor DC to DC convertors.
The 1 kwh ultra-capacitors are huge and there are none of them shown on their site.

Ken@Japan

Tesla do not say who produces their 18650 cells, but Sanyo, Kokam, LG-Chem and A123 all have LiIon cells capable of putting out up to 3.5 kW per kg. Admittedly, these are their "power" cells, but you could produce the Tesla's 200 kW with a LiIon pack weighing as little as 57 kg (a fifth of the current Tesla pack weight).

http://mysite.wanadoo-members.co.uk/ecotech/ecot.htm

I've thought for a while that this would be a good starting point for a series-hybrid engine:

http://www.daihatsu.com/motorshow/to...dex.html#2cddi

2 cylinder 659 cc diesel engine, 37kW at 3,500 rpm, meets Japan 2005 emissions regulations. I can't find the weight listed anywhere, but it must be prettly light.

http://mysite.wanadoo-members.co.uk/ecotech/ecot.htm

Do you really have to use such annoying language - how would you like it if others talk that way to you?


Tesla doesn't give out much information on their energy storage system, but I suspect that they do not use ultracapacitors, at this time, undoubtably for good reasons - availability, design & production cost, simplicity, etc. , although they certainly do have large capacitors on the DC bus.
To supply the energy off of their DC bus for the peak load would require .2 kwh. However, since they have ample power capability in their battery pack, it would not be necessary for them to use ultracapacitors, it would just be more efficient as you would loose ~15% of regen energy by recharging the batteries, and also reduce the life of the battery pack. With the series hybrid, more significant energy gains can be obtained by using capacitors, since the generator output would also not loose the 15% charging inefficiency factor that the Tesla looses by storing all of its energy in the battery bank.

1 kwh of ultracapacitors would weigh 8 lbs, according to:
http://thefraserdomain.typepad.com/e..._ultracap.html
Certainly you don't need to use ultracapacitors in the series hybrid design, nor likely would you if you were modifying a Tesla, as that would be excessive redesign - you would simply use a large enough battery pack to do the job. This is exactly the same problem that the Prius has in sizing their battery pack to store some of the regen energy - .3 kwh out of their 1.2 kwh battery pack. So with the Tesla with at most 5 times more energy to store 5 x 1.2 kwh = 6 kwh. About what I estimate would be an appropriate size for a Tesla series hybrid. Of course, you could also go larger if you wanted, esp if you want plugin capability.

The mature design of either the most energy efficient EV or Series HEV or even Parallel HEV, for that matter, would be to use ultracapacitors to store regen energy incl. that of normal hills - and batteries for anything excess to that.