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Sorry for the mis-quote.Rob Dekker wrote:
"Mark Thorson" <nospam@sonic.net> wrote in message news:4889025D.EB3033EB@sonic.net...
Bret Cahill wrote:
The small cell phone or lap top batteries wired in parallel would
charge up in a couple of minutes.
10 recharges during a work-day
I was planning for 6 - 10 an hour.
Every time the tractor makes it across the field or back it recharges.
Laptop batteries are typically good for about 1000 charges
before becoming seriously degraded. �Your hypothetical
tractor would need a fresh set of batteries about every
2 weeks. �You haven't taken this major cost into account.
How would this cost be any different than the plug in hybrid or EV
like the Tesla?
Because a car is only charged once or twice a day.
If we assume an 8-hour shift, your tractor
is being recharged 48-80 times a day. If this
big, expensive tractor is used for multiple
shifts, it could be much higher than that.
You'll be producing mountains of dead, expensive
batteries. There isn't enough hazmat landfill
to handle them all.
Please RECYCLE batteries.
The metals in there are valuable (especially for lithium-based cells).
Although for tractors, you probably would not use Li-ions that are designed for small applications, although even these would
already be economical (as Tesla shows).
But for tractors, the low-cost, high energy density molten salt batteries (Zebra's, sodium/sulfur etc) are excellent :
http://en.wikipedia.org/wiki/Molten_salt_battery
Cheap, powerfull, thousands of cycles, and easy to recycle.
With their high operating temperatures, these are rather 'clumsy' for small applications.
But for tractors, busses and anything big, they should be great.
Rob
The site give the specs for a Zebra battery at 90 Wh/kg.
I agree. Although ludicrous is a big word, 'currently unrealistic' is certainly applicable.Based on what is posted on the Wiki site and the thread
here, the idea that this technology, as it is today, can
be a practical alternative to diesel in tractors is totally
ludicrous. And that is without considering the purchase
price of the batteries and charging equipment, or the
cost of installing the charging equipment.
And tend to be pretty scathing about loons like Brat.Rod Speed <rod.speed.aaa@gmail.com> wrote
John Larkin <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote
BretCahill@peoplepc.com wrote
Diesel power is now almost 4X the cost of the grid. Battery cost
is 2X - 3X grid cost and the combination is just now about equal
to or in some areas already below the cost of diesel.
Unlike electric road vehicles and plug in hybrids, battery energy
density is not much an issue with farm tractors which can recharge
every few minutes. 90 watt/kg is more than enough energy density
for almost all farm operations.
For example, for a 400 HP articulated diesel tractor engine
equivalent, two 350 LB batteries -- about the same energy as 2
gallons of diesel -- are cantilevered off both sides of the
electric tractor, each with a vertical conductor mounted on top to
contact wires at the ends of the field.
When the tractor reaches the right hand U turn end of the field the
left outrigger picks up a recharged battery. After the U turn the
outrigger drops off the discharged battery for charging where it
can be picked up on the next lap.
The right side battery is swapped out at the other end of the field
when the left hand U turn is made.
Depending on use the batteries last a month or so, changed and
recycled much less frequently than motor oil.
If such a system was available now, it would be more cost effective
than replacing with diesel.
There are all kinds of farm situations and there will be all kinds
of solutions. In the long run for some applications, it might be
cheaper to eliminate the battery cost and run straight from the
grid, either by trolley wiring the entire field or with something
like a pivot structure to deliver the power to a tractor.
The original single battery single wire idea where the driver waits
at the end of the field for a recharge was the absolute cheapest
easiest electric tractor to prototype and demonstrate. It was just
a way to get started.
Have you presented these ideas to any actual farmers?
Have a heart, you want them to die laughing ?
I've spent a little time on farms. Farmers are generally
pretty inventive people, and are inclined to try all sorts
of things to improve productivity or just have fun.
Corse it is, particularly with the price of diesel what it is currently.It's impossible that some goodly number of them haven't already
considered all sorts of options to save energy, electrically or otherwise.
Its obviously zero. That stands out like dogs balls.Bret hasn't filled us in on his experience with farming,
or electrical engineering, or mechanical design.
Diesel power is now almost 4X the cost of the grid. ?Battery cost is
2X - 3X grid cost and the combination is just now about equal to or
in some areas already below the cost of diesel.
Unlike electric road vehicles and plug in hybrids, battery energy
density is not much an issue with farm tractors which can recharge
every few minutes. ?90 watt/kg is more than enough energy density for
almost all farm operations.
For example, for a 400 HP articulated diesel tractor engine
equivalent, two 350 LB batteries -- about the same energy as 2
gallons of diesel -- are cantilevered off both sides of the electric
tractor, each with a vertical conductor mounted on top to contact
wires at the ends of the field.
When the tractor reaches the right hand U turn end of the field the
left outrigger picks up a recharged battery. ?After the U turn the
outrigger drops off the discharged battery for charging where it can
be picked up on the next lap.
The right side battery is swapped out at the other end of the field
when the left hand U turn is made.
Depending on use the batteries last a month or so, changed and
recycled much less frequently than motor oil.
If such a system was available now, it would be more cost effective
than replacing with diesel.
There are all kinds of farm situations and there will be all kinds of
solutions. ?In the long run for some applications, it might be
cheaper to eliminate the battery cost and run straight from the
grid, either by trolley wiring the entire field or with something
like a pivot structure to deliver the power to a tractor.
The original single battery single wire idea where the driver waits
at the end of the field for a recharge was the absolute cheapest
easiest electric tractor to prototype and demonstrate. ?It was just
a way to get started.
Bret Cahill
Yes they did.Rod Speed wrote
John Fields <jfields@austininstruments.com> wrote
they blew up, among other things, embassies, ships,
Yes.
and the world trade towers,
Nope. And they didnt expect them to implode like they did either.
They didn't implode.
Same thing, different words.They suffered cascade failure,
Not with skyscrapers it aint.a well known engineering phenomenon.
They were always designed to survive more than just the current aircraft.Those towers had only ever been designed to accept the
impact of a Boeing 707, the largest aircraft of its day.
Nope, its never about asbestos with those.Furthermore, building codes had reduced the effectiveness of
fire protection in the higher levels due to concerns about asbestos.
We did, no one has been able to hijack an aircraft in the US again.I dare say we'll learn from all that.
That claim about sloppiness was only true about a small subset of them.John Fields wrote
Rod Speed wrote
John Fields <jfields@austininstruments.com> wrote
Rod Speed <rod.speed.aaa@gmail.com> wrote
Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
Bret Cahill wrote
When looking at battery tech for (PH)EVs, I came across an
interesting experiment converting a school bus into an
electric vehicle.
And if it was so great whey aren't they in volume manufacture right now ?
Coz the oil companys use terrorists to blow up the factorys, silly.
Actually, they tried to get some terrorists to blow up the
school bus, but they burned their lips on the exhaust pipe.
Yep, those damned rag heads aint exactly rocket scientist material.
Well, that was supposed to be a joke, but if you want to get serious
about it they blew up, among other things, embassies, ships, and the
world trade towers, so they weren't exactly stupid, were they?
They exploited vulnerabilities (a.k.a. sloppiness) rather than materials technology.
Its always possible to do terrorist atrocitys.Rod Speed wrote
Yep, those damned rag heads aint exactly rocket scientist material.
Despite the CIA's best intel and the Iraq war !
Thats a large part of it.Rod Speed wrote
Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
Rod Speed wrote
Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
Rod Speed wrote
Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
Rod Speed wrote
Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
Ever heard of OPEC ?
OPEC doesnt determine the price of oil.
Well no, ultimately 'the market' and speculators do that so we could say Wall St etc is to blame.
Yep, hence my original comment.
I dare say we could debate factors of this at length and it would be
quite interesting but I think there are other more important fish to fry.
Fried fish is bad for you.
Have you ever had British 'fish and chips' ?
Yep, and that has been proven to be bad for you.
Has it ?
Yep. Fried food is the main reason why the english are
much worse health wise than the mediteranean diet.
I don't think it's quite as simple as that.
No one ever said it was, just that its bad for you.Nor exclusive to the English/British.
The mediterean diet aint about frying in olive oil.Foof fried in lard as was once typical in the North (pig fat) yes !
Fied in olive or other vegetable oil (as in the mediterannean) no.
The english do eat quite a bit of fried food, and thats one of the reasonsIn any event I eat little fried food.
That fucks up the taste of fish and chips.And when I do I like to use olive oil.
Pizza, but I like almost all wog food except stupid quail.I rather thought the opposite as long as veg oil is used.
Nope.
Tastes good anyway. Ever tried it ?
Yep. It used to be my main fast food before hordes
of immigrants showed up with much better fast food.
Any suggestions ?
Nope, its much worse in that respect.It's a fine meal.
That has been proven to be bad for you.
Please cite.
Too lazy.
Admittedlyt I prefer poached salmon.
I prefer trout myself.
A tricky one.
Not for me.
I'll stick with salmon though.
Too polluted.
Depends where it comes from.
That was a joke, Joyce. Right over your head. Look it up.Don't even get me started on raw salmon.
Wot abart raw prawns ?
No, they need ideally to be freshly cooked on the boat coming in.
Bugger off, Pauline.Those are as fresh as they get. Have tasted such in Norway.
I have no argument with you.
Have you no sense of common decency what so ever ?
I certainly hope I do.
No evidence of it.
We see things from slightly different perspectives
maybe, but I think we are are in broad agreement.
That cant be allowed to continue.
Explain ?
You're sposed to say Please Explain.
Fine. Please explain.
Dont forget what that did to the cat.I AM aware of your reknowned TROLL status.
I'm not falling for that one. I'd rather share ideas.
Clearly no sense of common decency whatever.
Please address my suggestion.
What suggestion ?
Oh I'm puzzled now.
Disagreeeing is illegal.Why disgreee over nits ?
Then you need your ears tested.Rod Speed wrote
John Fields <jfields@austininstruments.com> wrote
Rod Speed <rod.speed.aaa@gmail.com> wrote
John Fields <jfields@austininstruments.com> wrote
Rod Speed <rod.speed.aaa@gmail.com> wrote
Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
I dare say we could debate factors of this at length
and it would be quite interesting but I think there
are other more important fish to fry.
Fried fish is bad for you.
Depends on what you fry it in.
Nope, frying is bad for you.
Got some data?
Yep, http://www.google.com.au/search?hl=en&q=frying+grilling+health
Sounds a bit contentious to me honestly.
The problem aint what it does to the food, the problem is what it does to the humans who eat it.I doubt that gentle (low temperature) frying does much harm to any food.
Dont need any of that, France has shown that its perfectly possible.If you don't like my solutions then post your own.
Either lead follow or get out of the way.
Nuclear power.
Show yer calculations including the cost of stainless steel.
Not in any other first world country either.Nuclear proliferation is a non-issue for nuclear power.
At least not in the U. S. where every WalMart has MX missiles.
You wouldnt know what a dead horse was if one bit you on your lard arse.It is an issue in global affairs, but it is distinct from nuclear power. ?
Yer floggin' a dead horse.
You wouldnt know what a real leader was if one bit you on your lard arse.The number of nuclear power generating reactors needed by the
Manhattan Project was zero. The only link between nuclear power
and nuclear proliferation is as a supply of electricity to the enrichment
plant. The israelis still have not built a power reactor, and the
canadians have been looking at peaceful nuclear reactor
applications for over sixty years-- with no bombs built!
Not that I have anything against nukes but if you digress too
much then you won't git them to believe you are a leader.
Nope.The science of waste disposal has long since been solved.
The political problem of waste disposal is being held up by
environmentalists for no good scientific reason-- they just
want to stop nuclear power (and force us to burn coal).
Nuclear power will allow you to power those
electric tractors that you are so fond of.
Actually solar will do just fine.
Nope, batterys wont work with farm machinery that cant be on the grid.Without the cheap electricity that nuclear power is proven to be able
to deliver, voters will have to choose between burning coal, or a
drastically reduced standard of living. ?Short of an environmentalist
dictatorship, we can be fairly certain of increased coal burning,
with global warming prevention abandoned as 'too expensive'.
The hydrogen economy is stymied by electricity being
too expensive. Nuclear power will solve that problem.
The real problem is a cheap battery.
Just another number plucked from your arse. We can tell that from the smell.Mechanical energy from diesel electric locomotives costs 35 cents/kW-hr.
Just another number plucked from your arse. We can tell that from the smell.The grid is only 10 cents/kW-hr.
Just another number plucked from your arse. We can tell that from the smell.UP's main line through the desert requires 1 GW.
Just another number plucked from your arse. We can tell that from the smell.Over a year the grid costs less than a 1 billion to power UP's main line's 25,000 trains.
Just another number plucked from your arse. We can tell that from the smell.Right now UP is paying 3.5 billion / year in diesel just for their main line.
Just another number plucked from your arse. We can tell that from the smell.Now how much wire can you string out in the desert on 2.5 billion dollars a year?
No thanks, its been so comprehensively analysed that it only makes sense for you to read up on that.Rod Speed wrote
There's a reason for the dramatic difference in the health
consequences of the english and mediteranean diet.
You have the floor. Please elaborate on it.
'think' again. No one who had could ever come up with such a hare brained battery swap scheme.On Mon, 28 Jul 2008 19:50:54 -0700, John Larkin wrote:
On Tue, 29 Jul 2008 07:08:26 +1000, "Rod Speed"
rod.speed.aaa@gmail.com> wrote:
John Larkin <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:
On Mon, 28 Jul 2008 10:09:10 -0700 (PDT), BretCahill@peoplepc.com
wrote:
Diesel power is now almost 4X the cost of the grid. Battery cost
is 2X - 3X grid cost and the combination is just now about equal
to or in some areas already below the cost of diesel.
Unlike electric road vehicles and plug in hybrids, battery energy
density is not much an issue with farm tractors which can recharge
every few minutes. 90 watt/kg is more than enough energy density
for almost all farm operations.
For example, for a 400 HP articulated diesel tractor engine
equivalent, two 350 LB batteries -- about the same energy as 2
gallons of diesel -- are cantilevered off both sides of the
electric tractor, each with a vertical conductor mounted on top
to contact wires at the ends of the field.
When the tractor reaches the right hand U turn end of the field
the left outrigger picks up a recharged battery. After the U
turn the outrigger drops off the discharged battery for charging
where it can be picked up on the next lap.
The right side battery is swapped out at the other end of the
field when the left hand U turn is made.
Depending on use the batteries last a month or so, changed and
recycled much less frequently than motor oil.
If such a system was available now, it would be more cost
effective than replacing with diesel.
There are all kinds of farm situations and there will be all
kinds of solutions. In the long run for some applications, it
might be cheaper to eliminate the battery cost and run straight
from the grid, either by trolley wiring the entire field or with
something like a pivot structure to deliver the power to a
tractor.
The original single battery single wire idea where the driver
waits at the end of the field for a recharge was the absolute
cheapest easiest electric tractor to prototype and demonstrate.
It was just a way to get started.
Have you presented these ideas to any actual farmers?
Have a heart, you want them to die laughing ?
I've spent a little time on farms. Farmers are generally pretty
inventive people, and are inclined to try all sorts of things to
improve productivity or just have fun. It's impossible that some
goodly number of them haven't already considered all sorts of
options to save energy, electrically or otherwise.
Bret hasn't filled us in on his experience with farming, or
electrical engineering, or mechanical design.
Actually, I think he has,
Only by eating the products of the farming.but somewhat indirectly.
Thanks Graham,
I know that diesels (especially lately) are probably the most efficient
ICEs around.
But do you see any efficiency numbers for the new diesels ? Can't find
much on detroitdiesel.com.
I don't know the exact details for sure but very large marine diesels are
now hitting 50%. That's
impressive, especially when you consider what you might do with the waste
'co-gen' capacity.
Most diesels (as other ICEs) obtain best efficiency in a small RPM range andI believe the target for road diesels in the long term is in the region
of 40% or maybe a tad better.
Graham
About 120 electric (full size 22-30ft) busses are in operation (at least inThey are manufactured,
CITE !
Nope, because they are too small to make that viable."Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:488E473C.CDF2730F@hotmail.com...
..
Thanks Graham,
I know that diesels (especially lately) are probably the most
efficient ICEs around. But do you see any efficiency numbers for
the new diesels ? Can't find much on detroitdiesel.com.
I don't know the exact details for sure but very large marine
diesels are now hitting 50%. That's impressive, especially when you
consider what you might do with the waste 'co-gen' capacity.
That IS impressive..
I believe these, but where did you get these numbers ?
I assume they pertain to these monsters running at their optimal rate
(crusing at constant RPM and significant load).
About co-gen on a ship, assuming they don't need all the waste heat,
what's the temp of the exhaust ? There may be a way to get additional
energy from a second cycle (steam turbine or so).
I believe the target for road diesels in the long term is in the
region of 40% or maybe a tad better.
Most diesels (as other ICEs) obtain best efficiency in a small RPM
range and under 'ideal' (significant) load.
Is the 40% you mention here pertaining to that ? Where did you find
this number ?
Why would it not be close to 50% as with the
In vehicles, load varies wildly (unless you are crusing on the
freeway), so, well-tuned diesels performing in series hybrids
(essentially driving a generator) should be the most efficient way to
power a vehicle...
Sorry, but which part of my answer do you consider silly and why ?Rob Dekker wrote:
"Eeyore" wrote
Bret Cahill wrote:
When looking at battery tech for (PH)EVs, I came across an
interesting experiment converting a school bus into an electric
vehicle.
And if it was so great whey aren't they in volume manufacture right
now ?
They are manufactured, but not in large volume yet.
Many reasons for that. One important one because the cost of diesel only
recently became more expensive than grid+battery.
Remember oil was HALF the cost last year around this time (remember
$70/barrel?).
It has been only been a few years that even diesel-hybrids became
competitive with standard diesels.
Diesel-hybrids (especially series hybrids) already have full electric
drive, so now that battery+grid became cheaper than diesel, I
expect a lot plug-in hybrid diesels to emerge (retrofit bigger batteries
on existing hybrids, and on new vehicles), and electric and
plug-in hybrid busses/delivery vans will almost certainly take off too.
All this is assuming that price of oil is not gotta go down below $100
any more. If that happens, many applications will drop back
to simpler ICE technology.
Couple of big problems remains : how fast can the world increase battery
production ? And which battery technology can expand
fastest...
The free market should be able to determine that though.
Since ZEBRAs use cheap production materials, and fairly simple
production process, I give them a very good chance of becoming a
dominant battery technology for PHEVs and EVs.
Pitty that only one manufacterer in the world makes them (MES-DEA in
Switzerland).
I wonder how many patents are still open on ZEBRA technology. Patent
litigation and negotiation could slow down investment and
production of battery-tech.
That is a truly SILLY answer.
That aint what he was demanding a cite for.Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote
When looking at battery tech for (PH)EVs, I came across an
interesting experiment converting a school bus into an electric vehicle.
And if it was so great whey aren't they in volume manufacture right now ?
They are manufactured,
CITE !
About 120 electric (full size 22-30ft) busses are in operation
(at least in 2005) in the US (see page 14 of this report).
http://www.navc.org/Electric_Drive_Bus_Analysis.pdf
That aint what he was demanding a cite for.These busses are produced by a number of manufacturers. Blue Bird,
Electric Fuel Corporation and a spectrum of Chinese companies.
More fool you.Once again, the market was not ready for full EV busses in 2005
(when this report was written), but with the recent (since last year)
increase in fuel prices, the market is changing fast. I still expect
hybrid-electric drive busses to do better than full electric,
Yep, fuck all were actually stupid enough to bother with electric busses in any format.simple because bus operators are normally slow to
change their fleet to something drastically different.
Fuck all of them do.And I don't blame them. Still, as long as the new busses have electric drive,
And when they aint, it aint.the step to plug-in and to full EV is fairly minor.
And when they aint, it cant.Could be done with retrofit afterwards.
And the obvious approach on disposal is to design them so they canrlbell.ns...@gmail.com <rlbell.ns...@gmail.com> wrote
BretCah...@peoplepc.com wrote
If you don't like my solutions then post your own.
Either lead follow or get out of the way.
Nuclear power.
Show yer calculations including the cost of stainless steel.
Who are you to demand such? When you are challenged all that you do is bluster.
The nuclear powerplants operating in the US are making
huge piles of profits, while paying into the disposal pool.
It has more to do with a mindless reaction to 3 mile island.Follow along, or get out of the way.
Where's the leadership?
Nuclear proliferation is a non-issue for nuclear power.
At least not in the U. S. where every WalMart has MX missiles.
It is an issue in global affairs, but it is distinct from nuclear power. ?
Yer floggin' a dead horse.
The number of nuclear power generating reactors needed by the Manhattan
Project was zero. ?The only link between nuclear power and nuclear
proliferation is as a supply of electricity to the enrichment
plant. The israelis still have not built a power reactor, and the
canadians have been looking at peaceful nuclear reactor
applications for over sixty years-- with no bombs built!
Not that I have anything against nukes but if you digress too much
then you won't git them to believe you are a leader.
if you have nothing against nukes, why are you not trying to promote it?
The science of waste disposal has long since been solved. ?The
political problem of waste disposal is being held up by
environmentalists for no good scientific reason-- they just want to
stop nuclear power (and force us to burn coal).
Nuclear power will allow you to power those electric tractors that
you are so fond of.
Actually solar will do just fine.
The required collector area 4 square meters for every three
kilowatt*hours, divided by the charge time in hours and divided again
by the efficiency of the collector. A full battery charge must be
collected within the time that a charge is used, or the tractor will
be sidelined for lack of energy. The rooftops of the typical
collection of farmhouse, barn, and outbuildings will not have enough
area to support it all.
Without the cheap electricity that nuclear power is proven to be
able to deliver, voters will have to choose between burning coal,
or a drastically reduced standard of living. ?Short of an
environmentalist dictatorship, we can be fairly certain of
increased coal burning, with global warming prevention abandoned
as 'too expensive'.
The hydrogen economy is stymied by electricity being too expensive.
Nuclear power will solve that problem.
The real problem is a cheap battery.
A cheap battery is a useless lump without energy to charge it.
Electrifying the transport sector will require a many-fold increase
in the electrical power grid. Natural gas has the problem that it
will also run out, so we are stuck with nuclear, so we may as well
make a virtue out of necessity.
The reason we don't have more nuclear plants has nothing to do with
environmentalists, it has to do with economics and right-wing ideology.
Nope, because they have fewer viable alternatives. Japan too.France has lots of nuclear plants, and that's because they were
not tied to phony arguments about the wonderful private sector.
Or dont bother with the socialists and do it the way the Japs did it with the rightards doing it.If you want the gummint to subsidize nuclear plants (which
it does, in various ways,) then you should hire the socialist
Frenchies to build and run them in their terribly inefficient
socialist top-down regulated and uniform manner.
Wrong, the frogs have managed to do that fine.And now that I think about it, I guess they aren't so
inefficient, since they have no problem relying on
nuclear power for what---80% of their electricity?
The other problem that you have with nuclear as a solution
to CO2 or other issues is that you just can't build the things
fast enough, even if you streamline the regulatory process.
Nope.You have to get an enormous amount of capital together,
Nothing like the coal fired power station it replaces would be.you need stuff like cement (big CO2 source),
It was perfectly possible to train far more of those than would everyou need qualified welders,
Nope, there is no on and on.and on and on.
No need for new tech with nukes either.In the short term of 20-30 years the absolute easiest,
cheapest and largest improvement would come from
conservation and efficiency. No need for new tech.
Nope, not one modern first world country is even self replacing on population now if you take out migration.Oh yeah and maybe some reduction in birth rates.
Trivially fixed by not doing it for too long.Rod Speed <rod.speed.aaa@gmail.com> wrote
I doubt that gentle (low temperature) frying does much harm to any food.
The problem aint what it does to the food, the
problem is what it does to the humans who eat it.
Well, yeah, but it's the acrylamides that are developed in the food
when it's fried (or roasted or grilled) for too long that's the problem,
Nope, not when you get a clue about how long you do it for.so it _is_ what it does to the food that's the problem.
Wrong again. The real problem is whats used to fry it in.And then, it's only a problem if the fried food is high in carbohydrates.