ZEBRA electric school bus



Then why did you suggest it?
Care to try another strawman?
I haven't covered this issue yet but I'm guessing it would take up to six years, about the time diesel is $25/gallon, to electrify most basic food crop farms.
In overall costs, grid battery is already competitive or cheaper than diesel in many areas. It would be foolish to replace an old diesel with a new diesel when grid battery will not skyrocket in operating cost.

You don't think intellectual property requires work, both the original concept as well as the development? You think copyright laws and patent rights are a scam?
Maybe Madison screwed up with Art. I, Sec. 8 of the U. S. Constitution?
Or are you so ashamed of your "contributions" you won't share them with anyone?
Maybe you are a loser in your own mind.
If you are a loser in your mind, then you are certainly a loser in my mind.
Bret Cahill
"Only nobodies are ever modest."
-- Goethe
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We've done the math.
Diesel is already 35 cents / kW hr.
Battery + grid is only 30 cents / kW hr, 27 cents in the TVA area.

Where is this bio diesel being produced?
Is there a pipeline that delivers it anywhere?
Grid battery is all off the shelf.
Bret Cahill
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Pathetic.
Totally huge.
Nope.
Ain't gonna happen.
Nuke.
Cite?
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wrote:

--
True, but the error was. ;)

http://www.merriam-webster.com/dictionary/negligent
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...

English is not my native language, but I should have known better anyway. Thanks for pointing out the (other) error.
Rob
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wrote:

--
My pleasure.

BTW, your English is excellent.
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No, we always do that. Not 10 or 100, just 1,000.

I've read that basic Li-ion batteries are available for $500/Kwhr. Zebra batteries are meant to be cheaper than that.
However, from Wikipedia: "The ZEBRA battery has an attractive specific energy and power (90 Wh/ kg and 150 W/kg). The liquid electrolyte freezes at 157 C, and the normal operating temperature range is 270-350 C. The -alumina solid electrolyte that has been developed for this system is very stable, both to sodium metal and the sodium chloroaluminate. Lifetimes of over 1500 cycles and five years have been demonstrated with full-sized batteries, and over 3000 cycles and eight years with 10- and 20-cell modules. Vehicles powered by ZEBRA batteries have covered more than 2 million km. Modec Electric Van uses ZEBRA batteries for the 2007 model."
3,000 charges for a $20,000 battery would be 7c plus amortisation costs.

You should be able to get night time electricity more cheaply.

Or the life has to treble, which is already achievable.
The problem with Zebra is that it needs to be kept at 250C or so. So it needs to be very well insulated. That's less of a problem for a 100KW (1 ton) battery than a 13KW car battery.
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Good points ! Thanks.
You are right : with 3000 charges, capital cost should be around 7cts/kWh, and with lower cost night-time electricity (maybe 7cts/kWh), brings overall cost (excluding maintenance and failure etc) to around 14 cts/kWh (rather than the conservative 33cts/kWh that I calculated).
Pricing of batteries (wholesale) is always somewhat murky. There are no pricelists on-line, and you have to read between the lines. For example, the ZEBRA-bus report stated $20,000 for the 107kWh pack ($200/kWh) for ZEBRAs ordered in volume (the report states order of 30,000 ZEBRAs). In small orders they are still more expensive (around $500/kWh). Lithium-ion seems to be also in that range, although the Wiki page refers to a Chinese manufacturer that apparently sells 10kWh Li-ion packs for $2000 (in volume).
The ZEBRA indeed has to be kept 'hot', but that might not be too problematic. I read that it requires only 40W to keep the pack hot, and it takes days before the pack solidifies if left unattended. For bus operators, that should not be a problem, since typically busses return to their terminal at the end of the day. Instead of filling them up with diesel, they would now just have to be plugged in. Once plugged the pack keeps itself hot (using 40W).
Either way (lithium-ion or ZEBRA, temp-management or not), the calculations show that electric busses should be quite cost-competitive with diesel right now. I'm curious to see how bus operators and manufacturers respond to this. It's an interesting time.
Thanks again !
Rob

No, we always do that. Not 10 or 100, just 1,000.

I've read that basic Li-ion batteries are available for $500/Kwhr. Zebra batteries are meant to be cheaper than that.
However, from Wikipedia: "The ZEBRA battery has an attractive specific energy and power (90 Wh/ kg and 150 W/kg). The liquid electrolyte freezes at 157 C, and the normal operating temperature range is 270-350 C. The -alumina solid electrolyte that has been developed for this system is very stable, both to sodium metal and the sodium chloroaluminate. Lifetimes of over 1500 cycles and five years have been demonstrated with full-sized batteries, and over 3000 cycles and eight years with 10- and 20-cell modules. Vehicles powered by ZEBRA batteries have covered more than 2 million km. Modec Electric Van uses ZEBRA batteries for the 2007 model."
3,000 charges for a $20,000 battery would be 7c plus amortisation costs.

You should be able to get night time electricity more cheaply.

Or the life has to treble, which is already achievable.
The problem with Zebra is that it needs to be kept at 250C or so. So it needs to be very well insulated. That's less of a problem for a 100KW (1 ton) battery than a 13KW car battery.
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Nope, pity about the capital cost.
Which might just be why so few bother with any form of electric bus.

Its obvious, they'll keep ignoring it.
It makes much more sense to use LPG or CNG in gasoline engines if you care about the cost of diesel.

Not with busses it aint.

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On Wed, 30 Jul 2008 07:07:26 +1000, "Rod Speed"
--
Have you never heard of "The Grid"?

JF

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Tad unlikely I havent seeing as I have used that term a number of times.
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On Wed, 30 Jul 2008 11:51:39 +1000, "Rod Speed"

--
Whoooooosh...

The grid _is_ a "buss", Mr. Clever.
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Some pathetic excuse for a troll claiming to be
desperately attempted to bullshit and lie its way out of its predicament and fooled absolutely no one at all, as always.
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Actually that $0.0002/whr.
$20,000 / (1,000 cycles X 100 kilowatt hours) = $0.20/ kWhr.
If it can cycle several thousand times, however, then the price of is only a few cents/kWhr
The cost of diesel increases that much in one year.

That could drop with cheap PV.

In sunny areas the bus could be plastered with PV which would be a significant savings.

Olive oil has 120 cal/serving (actually 120 kcal/15cc) or 8,000 kcal/ liter or 33 kWhr/gallon.

And that's when they are always running at optimum rpm.

So using my battery cost figure diesel is slightly more expensice than battery-grid right now.
Since we know diesel fuel will continue to spiral, it would be foolish not to replace diesel with battery-grid as soon as possible where ever possible.

That'll be true in a couple years anyway.

I think that's 20% recuperation per stop, not overall.
Bret Cahill
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snipped-for-privacy@peoplepc.com wrote:

Nope, because cheap PV aint gunna happen, you watch.

Wrong again. Pity about the cost of the PV and the kids vandalising it.

Different calories, stupid.

Which no bus ever does.

Wrong again.

It hasnt even spiralled yet.

Wrong again. It makes a lot more sense to see if it ever becomes economic.

Nope.
You're wrong.
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Totally huge.
Pathetic.
No way.
Cite?
Liar
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