Compressed air car nearing manufacture

[j]

They are right-at-the-edge of being practical for
the "peak shaving", so to speak, uses. For example,
when you're decelerating your car via motor-generator,
you're producing way too much power for transfer
into a battery. But if you could dump that electricity
over to a supercap, and then slowly feed it to
the battery, it almost works.

That's my take on it too. I think though, that you don't have to feed it
back, but use it for the next acceleration.

It seems to me that if you can limit the peak current drawn from the
batteries, that you would get a longer life out of them.

Given enough capacitor, peak torque could be impressive. The battery
would limit the horsepower.

At least, that is roughly how I see this. There seems to be some real
money in sales and investments ($.5B /year). Not all of that can be
small devices...

Jeff

 

[Jim Wilkins]

...
It seems to me that if you can limit the peak current drawn from the
batteries, that you would get a longer life out of them.

Given enough capacitor, peak torque could be impressive. The battery
would limit the horsepower.

Jeff

You really need to assume that the designer knows his job and matches
the battery with the motor. Tire slip limits the maximum starting
torque and braking deceleration.

Perhaps these caps would permit a less expensive battery but their
rapid voltage change complicates the electronics. They store half (or
less) the energy of a battery of the same peak voltage and charge
capacity because their constant-current discharge curve is a triangle
instead of a battery's near rectangle the same height and width.

jsw

 

[News]

They already know that your versionof the "air car"

I do not a version of the air car. You are senile and confused. Probably
beyond medical help by now.

 

[News]

On 5/16/2012 9:32 AM, News wrote:

I'm not sure if they are close there yet. But the power density is
very high, and for regenerative braking, or for quick burst of
acceleration that is very valuable.

For regen braking and acceleration busts they appear to be feasible. The
original 1997 Prius was to have a supercapacitors but at the last minute
they changed to batteries.

 

[News]

This is your thread News. You started the discussion. Are you
serious about discussing this or are you just trolling again?

I never troll. I inform you of events.

No, you read it again. it's you who snipped the quote which was that
Tata plans to: "complete detailed development of the technology" Their
words, not mine.

Yes, they are looking into the manufacturing side now. It is nice you are
getting it.

 

[News]

They are right-at-the-edge of being practical for
the "peak shaving", so to speak, uses. For example,
when you're decelerating your car via motor-generator,
you're producing way too much power for transfer
into a battery. But if you could dump that electricity
over to a supercap, and then slowly feed it to
the battery, it almost works.

R&D is being done right now on battery-supercap setups. Only hydraulic
accumulators can store most kinetic energy (90% plus) and give it back off
immediately. Chrysler with the EPA are developing a test minvan using this
hydraulic technology.

 

[News]

That's my take on it too. I think though, that you don't have to feed
it back, but use it for the next acceleration.

This is being used for urban stop-start trains.

 

[j]

You really need to assume that the designer knows his job and matches
the battery with the motor. Tire slip limits the maximum starting
torque and braking deceleration.

Perhaps these caps would permit a less expensive battery but their
rapid voltage change complicates the electronics. They store half (or
less) the energy of a battery of the same peak voltage and charge
capacity because their constant-current discharge curve is a triangle
instead of a battery's near rectangle the same height and width.

That certainly makes sense. But it appears they have solved the complex
electronics (buck boost mostly). Note the number of existing projects:

http://en.wikipedia.org/wiki/Electric_double-layer_capacitor#Automotive

I would think the winning features would be the low internal resistance
and perhaps the low cost.

At any rate, this was all unexpected to me, and shows how much money
there is in the margins of saving energy. At least for large vehicles
where the momentum lost is sizable. Toyota has a race car project
coming out though (Toyota TS030). And the Chinese have total supercap
buses that get a quick recharge at the stops.

I take your point that this is not needed for acceleration.

It's all rather interesting but I don't think it will make it into a
grocery getter anytime soon.

Jeff

 

[Jim Wilkins]

That certainly makes sense. But it appears they have solved the
complex electronics (buck boost mostly).

I have a couple of inverters here at home that can fully charge a
battery from a nearly discharged one.

We can do incredible things in the research lab with enough funding.
The decisions governing energy are almost always economic, except for
national defense where Stirling engines in subs and missile and
disposable precious-metal batteries cost less than losing your
freedom.

Were you Green enough to buy a Segway?

jsw

 

[Jim Wilkins]

We can do incredible things in the research lab with enough funding.

Not sure if anyone will appreciate it, but I just found out that the
1971-vintage HP Spectrum Analyzer I bought at a flea market depends on
this magic crystal:
http://en.wikipedia.org/wiki/YIG_sphere

This one sweeps smoothly from 2 GHz to 4 GHz.

jsw

 

[j]

I have a couple of inverters here at home that can fully charge a
battery from a nearly discharged one.

We can do incredible things in the research lab with enough funding.
The decisions governing energy are almost always economic, except for
national defense where Stirling engines in subs and missile and
disposable precious-metal batteries cost less than losing your
freedom.

I wonder how much longer Germany could have held out if it's tanks and
planes were 20% more efficient?

The WWII P51 Mustang gained the range needed because it was fuel
efficient. As far as us today, the military has it's own strategic
reserves and in flight refueling. I don't care about the mileage in an F22!

Were you Green enough to buy a Segway?

Not me, but there are a lot of Segways here. Popular for tours.

I'm only really green where it saves money and doesn't cost a fortune.
For me that is solar thermal. And with the cost of water, low flow
toilets (plug for Kohler Super Flusher).

The odd thing about energy conservation is that this rarely benefits the
poor who are mostly about using energy. You need to have some money to
start with before you can think about saving some!

Jeff

 

[News]

I wonder how much longer Germany could have held out if it's tanks and
planes were 20% more efficient?

Not at all as they were going to get beat anyhow. British, US and Soviet
industry just crushed the poor murdering blighters.

The Segway inventor has spent a lot of money on improving the Stirling. He
drives around ain Stirling-electric hybrid car and is proposing a
Stirling-electric scooter.

 

[Jim Wilkins]

I wonder how much longer Germany could have held out if it's tanks
and planes were 20% more efficient?

The WWII P51 Mustang gained the range needed because it was fuel
efficient. As far as us today, the military has it's own strategic
reserves and in flight refueling. I don't care about the mileage in
an F22!

In rec.aviation.military we've hashed out WW2 technology ad nauseam.
There wasn't that much difference in technical ability because each
side could examine the others' wreckage and test captured examples.
The big difference was the demands of remote offense vs local defence.
Germany never had more than a small fraction of the US and British
ability to project power overseas, they expected and planned for a
short, local land war. They had more trouble moving supplies by road
and rail across Russia than we did shipping them half way around the
world.

The odd thing about energy conservation is that this rarely benefits
the poor who are mostly about using energy. You need to have some
money to start with before you can think about saving some!
Jeff

I've worked on that issue and made my house and appliances
considerably more efficient by simple, inexpensive changes like
replacing the shower head with a sink spray that shuts off when
released, drying laundry outdoors year-round, learning to live with a
smaller refrigerator and opening windows to vent with night air
instead of running the AC. I have an antenna for TV and dial-up
internet, which save over $100 a month vs cable.

They seem to demand too much prior planning, attention to detail and
change to accustomed behavior for most people. For example I have to
watch the weather forecast to plan when to do laundry, and calculate
the dew points or comfort index of indoor and outdoor air to see if
nighttime venting is worthwhile when the humidity is high.

jsw

 

[Jim Wilkins]

...
The Segway inventor has spent a lot of money on improving the
Stirling. He drives around ain Stirling-electric hybrid car and is
proposing a Stirling-electric scooter.

I know, but I signed a non-disclosure agreement and can't discuss it.

 

[News]

I know, but I signed a non-disclosure agreement and can't discuss it.

A google brings it up, so you can now

 

[Vaughn]

I never troll. I inform you of events.


Yes, they are looking into the manufacturing side now. It is nice you
are getting it.

But you aren't"getting it". Despite your title to this thread, there is
nothing in that press release to indicate that any "compressed air car"
is "nearing manufacture" anywhere.

 

[Jim Wilkins]

A google brings it up, so you can now

Yet another subject you don't understand.

 

[Bob F]

I do not a version of the air car.

Now there's a meaningless statement.

You are senile and confused.
Probably beyond medical help by now.

Speaking of the devil.

 

[News]

Speaking of the devil.

Please speak of him if you like.

 

[News]

But you aren't"getting it".

I did get it. I read the Tata press release. You know, about this car you
said would never work because you did some sums.