Grid-Battery "Hybrid" Tractors

Steam is mechanically far simpler than ICE.

But far more complicated, more expensive, required more maintenance
and is less efficient than than an electic motor powered by bio mass
burned at a power plant.

umm, hasn't this argument degenerated to whther the steam boiler is large
one at a power station or lots of little ones in paddocks?

Hopefully.

Economies of scale make the power plant much safer.


Bret Cahill

 

[John Fields]

On Tue, 22 Jul 2008 16:27:09 -0700 (PDT), BretCahill@peoplepc.com
wrote:

Not that pausing a few minutes is a problem either but a fast
recharging battery just isn't a serious issue.

All that is necessary is make the cells smaller.

The smaller the cell, the faster the recharge.

This should be common knowledge.

Bret Cahill

Show us a link to a datasheet for such a battery.

Meanwhile, consider a AA size battery with, say, a 2 AH capacity.
Consider charging it in one minute.

See the problem?

No, at least nothing compared to the problem of paying $30 billion a
year -- soon to be $100 billion/yr -- for diesel used in agriculture.

---
Avoiding the issue by changing the subject, are we???

The Issue has _always been_ liquid fuel costs.

---
Sorry, Charlie, nice try but the issue at the moment, brought up by
JL, is whether you can appreciate the economics of battery charging.

You're obviously clueless and decided to side-step by changing the
subject.

No matter, I'll explain it to you a little later on and then you can
claim you knew it all along, OK?
---

There is no reason to electrify the farms if diesel wasn't spiraling.

---
Blah, blah, blah...
---

If a battery with a capacity of 2 AH (120 ampere-minutes) needs to be
recharged in two minutes, then you've got to fill it back up with the
same amount of electricity, but you've only got 2 minutes to do it in,
so you've got to pump it in faster than it came out. ?

And it "came out" in 6 - 10 minutes.

The tractor is moving 6 - 10 mph.

---
So how long would you want to wait for the battery to charge up?

One minute? you'd still have to pump in at least 6 times as much
current as came out.

For 400 horsepower, the power into the motor would be:

400HP * 746W
P = ------------- = 298 400 watts
HP

and the current required from a 300V battery pack would be:

P 298 400W
Iout = --- = ---------- ~ 995 amperes
E 300V


Therefore, if you ran the machine for six minutes and recharged it for
one, The current into the battery would have to be:


Iout * Tout 995A * 360s
Iin = ------------- = ------------- = 5970 amperes
Tin 60s


Typically, to charge a battery fully you've got to put in 1.4 times as
much energy as you took out, which would increase that 5970 amperes to
about 6400 amperes.

Now, when you consider that that electricity has to come from
_somewhere_ and that is has to be brought into the field using
conductors of finite resistance, then the problem becomes even more
severe.
---

Alternatively, if the tractor is moving slowly, then it won't require
400 hp, and you'll _still_ have a short charging time.

---
You were the one who stipulated 400HP and now you're back-pedaling?

Typical trick for someone who doesn't know what he's talking about to
try to get off the hook.
---

You keep trying to dodge the fundamental reason this is a better
application of batteries than the wildly popular plug in hybrids:

---
Me???

All I've done is taken numbers that you've supplied and shown you why
what you advocate is impractical.

You, on the other hand, keep trying to move the goal posts in order to
try to make your position seem tenable.
---

Unlike EVs or plug ins the tractor never goes very far from the
charger.

---
It doesn't make any difference. Coulombs is coulombs and if you want
to fill a battery up in 1/10th the time it took to discharge it you'll
have to pump in ten times as much current during that time. More,
even, because there's no free lunch. See above.
---

The batteries can therefore be small and cheap and have short charging
times.

---
How small?
How cheap?
How short a charging time?

You obviously have no clue and know _nothing_ about battery chemistry.
---

And we haven't gotten to the favorable torque/rpm curve of electric
motors which allows a much smaller hp motor.

---
As if you knew anything about it before another poster bought it up.

Get on with it, then.

Let's see your analysis.

JF

 

[John Fields]

On Tue, 22 Jul 2008 21:29:54 -0700 (PDT), BretCahill@peoplepc.com
wrote:

Paying $100 billion a year for diesel for agriculture will _starve_
the population.

---
Got some numbers?

JF

 

[John Fields]

On Tue, 22 Jul 2008 21:45:32 -0700 (PDT), BretCahill@peoplepc.com
wrote:

Not that pausing a few minutes is a problem either but a fast
recharging battery just isn't a serious issue.

All that is necessary is make the cells smaller.

The smaller the cell, the faster the recharge.

This should be common knowledge.

Bret Cahill

Show us a link to a datasheet for such a battery.

Meanwhile, consider a AA size battery with, say, a 2 AH capacity.
Consider charging it in one minute.

See the problem?

No, at least nothing compared to the problem of paying $30 billion a
year -- soon to be $100 billion/yr -- for diesel used in agriculture.

---
Avoiding the issue by changing the subject, are we???

_You_ not "we."

The original issue was _always_ the $100 billion wasted on diesel.

---
But it's not the issue presently, what is is whether you understand
the economics of battery charging. You obviously don't and changed
the subject in order to skirt it.

JF

 

[John Fields]

On Tue, 22 Jul 2008 21:52:29 -0700 (PDT), BretCahill@peoplepc.com
wrote:

What farming operation requires 400 hp to go 0.5 mph?
Ploughing, broad acre sowing, harvesting.

Also a process I believe is called sub-soiling where a large machine turns
the soil from about 5 feet below the surface.

Then call in a service company with a bigger battery.

---
You're a fucking idiot and you're losing the argument.

JF

 

[John Fields]

On Tue, 22 Jul 2008 21:57:52 -0700 (PDT), BretCahill@peoplepc.com
wrote:

Not that pausing a few minutes is a problem either but a fast
recharging battery just isn't a serious issue.

All that is necessary is make the cells smaller.

The smaller the cell, the faster the recharge.

---
And the more expensive the finished battery cost per watt-hour.

The tractor only goes a mile between charges so a tractor battery
doesn't need a lot of watt-hours / work done.

---
Really?

Your 400 horsepower tractor, working for an hour, would need a battery
which can supply about 300KWH, (300 000 watt-hours) and if it's doing
it with an output voltage of 300V that means it needs to be rated for
an output of 1000AH at C/1.

That's a lot of watt-hours and a lot of work done.

True.

Not true.

The tractor only needs to make one "lap" between charges -- a few
minutes.

---
Did you miss the posts about when a tractor goes 0.5 MPH?
---

Any argument for plug ins is an *a fortiori* argument for grid-battery
powered tractors.

---
Just like any argument for bug zappers is an a fortiori argument for
the electric chair?

JF

 

What farming operation requires 400 hp to go 0.5 mph?
Ploughing, broad acre sowing, harvesting.

Also a process I believe is called sub-soiling where a large machine turns
the soil from about 5 feet below the surface.

Then call in a service company with a bigger battery.

There are dozens of farm service companies in agricultural areas
because the reality is no farmer needs the same equipment 24/7/52.

For example, if a farmer needed his 400 hp articulated tractor going
0.5 mph 356 days out of the year then he'ld be working about 10
feet^2 / sec.

That 774 hours or over 3 months of 8 hour days to complete just one
square mile.


Bret Cahill

 

What farming operation requires 400 hp to go 0.5 mph?

Ploughing, broad acre sowing, harvesting.

Then to do just one square at 0.5 mph:

Diesel: 17,000 gallons.

Diesel cost today: $85,000

Assuming the price of liquid fuel continues to increase at "only" 30%
a year:

Diesel cost in 2 years: $145,000

Diesel cost in 6 years: $425,000

And that's just one one time operation.

It's a whole lot cheaper to electrify, even if you have to buy 14,000
laptop batteries (twice that of the 200 kW Tesla) and install them
yourself.



Bret Cahill

 

[terryc]

On Tue, 22 Jul 2008 17:38:25 -0700, Rob Dekker wrote:

It's more likely that we will move to no-till agriculture.

Do you actually kno what no till agriculture is?

Hint, it involves a sod seeder instead of a combine & ploughing.

 

[terryc]

On Tue, 22 Jul 2008 21:29:54 -0700, BretCahill wrote:

Paying $100 billion a year for diesel for agriculture will _starve_
the population.

Just another tool in the fight against obesity.

 

[terryc]

On Wed, 23 Jul 2008 09:23:06 -0500, John Fields wrote:

Typically, to charge a battery fully you've got to put in 1.4 times as
much energy as you took out, which would increase that 5970 amperes to
about 6400 amperes.

Err, is this something to do with fast charging?
Heard 110% for C/10 in dep-discharge lead acid batteries, but not that
much.

 

[terryc]

On Wed, 23 Jul 2008 09:23:06 -0500, John Fields wrote:


notie this paragraph after I flicked the other answer....

Now, when you consider that that electricity has to come from
_somewhere_ and that is has to be brought into the field using
conductors of finite resistance, then the problem becomes even more
severe.

So instead of 415V supply, you just tap the 11Kv lines instead.

 

[terryc]

On Wed, 23 Jul 2008 14:01:27 -0700, BretCahill wrote:

There are dozens of farm service companies in agricultural areas
because the reality is no farmer needs the same equipment 24/7/52.

Lol, the problem with this idea is that farmers producing the same crop
generally all do the same job at the same time.

 

[terryc]

On Wed, 23 Jul 2008 14:18:19 -0700, BretCahill wrote:

It's a whole lot cheaper to electrify, even if you have to buy 14,000
laptop batteries (twice that of the 200 kW Tesla) and install them
yourself.

Actually, your system might work better if the tractor camewith a pair of
swappable battery packs that you dock in and out of a charging station.

It would certainly help the economics by reducing the peak power demands.

 

[terryc]

On Tue, 22 Jul 2008 18:34:37 -0700, Rob Dekker wrote:

True. But technically speaking, a 300 kWh battery is not completely rediculous : It will cost about $100,000 wholesale, and weigh
less than 2 ton.

Well, that is an interesting battery advancement.

For current deep-discharge lead acid, it would weigh 84 tonnes.
In LiPoly,it would currently weigh 20 tonnes.

 

[Don Bowey]

On 7/24/08 12:39 PM, in article
fbdc4423-0fc6-4476-a17d-2eda457c8ecb@i20g2000prf.googlegroups.com,
"BretCahill@peoplepc.com" <BretCahill@peoplepc.com> wrote:

Not that pausing a few minutes is a problem either but a fast
recharging battery just isn't a serious issue.

All that is necessary is make the cells smaller.

The smaller the cell, the faster the recharge.

This should be common knowledge.

Bret Cahill

Show us a link to a datasheet for such a battery.

Meanwhile, consider a AA size battery with, say, a 2 AH capacity.
Consider charging it in one minute.

See the problem?

No, at least nothing compared to the problem of paying $30 billion a
year -- soon to be $100 billion/yr -- for diesel used in agriculture.

---
Avoiding the issue by changing the subject, are we???

The OP issue is the tens of billions a year unnecessarily wasted on
diesel for agriculture.

That's the context, the _only_ reason for electrification of farms.

Are you just acting dumb or are you really this stoopid?

Since you persist in being an obstinate mule regarding proper posting form,
I don't know to whom you are responding or addressing.

IMHO you are the stupid one for posting this off-topic crap to the s.e.b.
Newsgroup.

Bret Cahill

 

Paying $100 billion a year for diesel for agriculture will _starve_
the population.

Just another tool in the fight against obesity.

What'll happen is they'll get together more often, i. e., public
transportation, and eat even more.


Bret Cahill

 

Not that pausing a few minutes is a problem either but a fast
recharging battery just isn't a serious issue.

All that is necessary is make the cells smaller.

The smaller the cell, the faster the recharge.

This should be common knowledge.

Bret Cahill

Show us a link to a datasheet for such a battery.

Meanwhile, consider a AA size battery with, say, a 2 AH capacity.
Consider charging it in one minute.

See the problem?

No, at least nothing compared to the problem of paying $30 billion a
year -- soon to be $100 billion/yr -- for diesel used in agriculture.

---
Avoiding the issue by changing the subject, are we???

The OP issue is the tens of billions a year unnecessarily wasted on
diesel for agriculture.

That's the context, the _only_ reason for electrification of farms.

Are you just acting dumb or are you really this stoopid?


Bret Cahill

 

And we haven't gotten to the favorable torque/rpm curve of electric
motors which allows a much smaller hp motor.

Didn't somebody already invent gears?

You _want_ to go Rube Goldberg?

If your goal is to cost farmers more money then that explains a lot.


Bret Cahill

 

Not that pausing a few minutes is a problem either but a fast
recharging battery just isn't a serious issue.

All that is necessary is make the cells smaller.

The smaller the cell, the faster the recharge.

This should be common knowledge.

Bret Cahill

Show us a link to a datasheet for such a battery.

Meanwhile, consider a AA size battery with, say, a 2 AH capacity.
Consider charging it in one minute.

See the problem?

No, at least nothing compared to the problem of paying $30 billion a
year -- soon to be $100 billion/yr -- for diesel used in agriculture.

---
Avoiding the issue by changing the subject, are we???

The Issue has _always been_ liquid fuel costs.

---
Sorry, Charlie, nice try but the issue at the moment, brought up by
JL, is whether you can appreciate the economics of battery charging.

Still trying to dodge the OP issue, the cost of diesel fuel?

Are you just acting dumb or are you really this stupid in real life?


Bret Cahill