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I suppose anything's possible with the right skills and equipment, but there are a couple challenges to overcome.

The Prius A/C condenser is integrated into a single module with the engine coolant radiator. If you're just replacing an existing Insight A/C, you could probably just reuse that condenser. Otherwise, it might be tricky to fit the Prius unit into the Insight. Probably not so hard in a Civic.

The DC electric motor needs a computer generated three-phase AC waveform. So you need an inverter. The Prius inverter is run by computers that are undocumented and expect to be integrated into a Prius system. You might be better off building your own inverter. You would need to figure out how to read the motor position sensor to get the waveform right.

As for physical mounting, you'll need to find experts at that sort of thing (or be one yourself).

Good luck. If you take this on, let us know how it goes. Take lots of pictures.
 

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Why bother?

That hybrid uses a PASSIVE electrical system. There simply is not enough electricity available to take advantage of electric A/C anyway. The supply will always be too small based on a design that depends primarily on braking to replenish the battery-pack... which is the sole source of electricity for the motor too.

Prius uses a PERSISTENT electrical system instead. That means there is always an ample supply of electricity. Having a second motor available, not just one as with the Honda, gives it the ability to top-off the battery-pack continuously. It also provides the ability, which is used frequently, to use a motor for propulsion without needing to get electricity from the battery-pack at all. That leaves far more available for electric A/C.

Also note that Prius has a battery-pack with a much higher energy density. That's also an important factor when considering electric A/C. Lower density means it can't run as long.
 
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"Can Prius........"

RSnyder said:
I suppose anything's possible with the right skills and equipment, but there are a couple challenges to overcome.

The Prius A/C condenser is integrated into a single module with the engine coolant radiator. If you're just replacing an existing Insight A/C, you could probably just reuse that condenser. Otherwise, it might be tricky to fit the Prius unit into the Insight. Probably not so hard in a Civic.

The DC electric motor needs a computer generated three-phase AC waveform. So you need an inverter. The Prius inverter is run by computers that are undocumented and expect to be integrated into a Prius system. You might be better off building your own inverter. You would need to figure out how to read the motor position sensor to get the waveform right.

:?

As for physical mounting, you'll need to find experts at that sort of thing (or be one yourself).

Good luck. If you take this on, let us know how it goes. Take lots of pictures.
 

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Re: Can Prius/Accord *electric* A/C be retrofit Insight/Civi

ElectricTroy said:
(please see subject)

troy
The 2006 Civic (coming out this fall) will have the same electric/gas A/C system that the Accord uses, and you might be able to refit one of those into your Civic. You'd just have to wait for one to be totalled, or maybe order a replacement from Honda directly.
 

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Discussion Starter #6
john1701a said:
Why bother? That hybrid uses a PASSIVE electrical system. There simply is not enough electricity available to take advantage of electric A/C anyway.
And yet, we see the Accord IMA using an electric A/C. So much for your theory that it's not possible.



Also, you've forgotten that Honda is *also* persistant..... constantly providing a charge from the engine-to-the-battery.

troy
 

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ElectricTroy said:
And yet, we see the Accord IMA using an electric A/C.
Not true. The A/C in Accord-Hybrid is not pure like in Prius.

It only runs from electricity in low-power mode. In high-power mode, the engine turns on regardless of the electricity supply available in the battery-pack. And in high-power mode, it is powered via a traditional belt rather than only electricity.


ElectricTroy said:
Also, you've forgotten that Honda is *also* persistant..... constantly providing a charge from the engine-to-the-battery.
Not true. Owners have clearly stated that too, coining "forced charge" to describe the mode in which on-the-fly charging takes place. That is far from constant.

Of course, constant is impossible anyway. Having only one motor means the creation of electricity cannot occur at the same time as the consumption of electricity. To do that, you need a second motor. Honda only has one.
 

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I'm not sure what the big deal is... I've driven in IMA equipped cars, and I've seen the battery charge while the car is crusing along, so that seems to pretty much shoot down John's theory that most of the energy comes from regenerative braking. I think he's fixated on the old manual transmission IMAs, which were a bit harder to charge while cruising (I think). It's funny that he jumped on the webmaster of greenhybrid.com for not distinguishing between manual and auto IMA equipped cars, but won't do the same himself.

And the electric A/C in the Honda systems is a smaller, supplemental A/C... this is true. But I haven't heard any complaints about it, so it seems to be doing the job.
 

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Discussion Starter #9
john1701a said:
ElectricTroy said:
And yet, we see the Accord IMA using an electric A/C.
Not true. The A/C in Accord-Hybrid... only runs from electricity in low-power mode.
Which is what I want. I'm satisfied with the low-power A/C in the Accord to keep my insight cool. I don't need to turn my car into a freezer.


CHARGING:
(1) Why would you want the motor to *drag* on the engine if, for example, you're climbing a hill??? You're losing power to the battery, that would be better directed to the wheels, to climb the hill. ----- I'm glad the Honda turns off charging during that situation.

(2) When the Honda is not in assist mode, then it's in a "trickle charge" mode (too small to be seen on the meter). When I'm driving to work at constant velocity, the battery gradually climbs from 2/rd charge to full in ~15 minutes time. My Honda spends 99% of its time in that "trickle charge" mode, and that's plenty of power to operate electric A/C.



Now let's stop this debate. I came here to ask a question, not to be distracted by John into "Honda hybrids suck" hate-trolling. If you have useful knowledge about adapting the Accord or Prius A/C to the Insight/Civic, please share.

Thank you,
troy
 

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What's wrong with Honda? They make popular high-quality products with high-reliability ratings. The discussion is about a DESIGN, not an automaker.

As for the difference between Manual & CVT, what are you taking about? Creating & Consuming electricity at the same time is impossible with only a single motor. You need two to provide both abilities simultaneously.
 

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ElectricTroy said:
My Honda spends 99% of its time in that "trickle charge" mode, and that's plenty of power to operate electric A/C.
TRICKLE == PASSIVE

Prius diverts 27% of the energy from the engine to the generator 100% of the time it is running. That is dramatically more than the Honda.

Regardless of the terminology chosen, they are NOT THE SAME. So don't expect the A/C to operate the same.
 

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john1701a said:
. . .Prius diverts 27% of the energy from the engine to the generator 100% of the time it is running. That is dramatically more than the Honda. . .
Hi John,
Please be a bit more careful what you say here. At higher speeds, unless your power demand is very high(floor it) or very low(warp stealth), very little of the energy obtained from the engine follows the electric path. (Power really since the energy is produced over time.) It's primarily mechanical energy transfer. The 27% number you cite is torque, not power. Power is torque times rotation, and the generator (MG1) rotates much slower than the wheels (MG2).

At low speeds, power transfer is almost all electrical.
 

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Discussion Starter #15
john1701a said:
ElectricTroy said:
My Honda spends 99% of its time in that "trickle charge" mode, and that's plenty of power to operate electric A/C.
TRICKLE == PASSIVE
Nonsense. Trickle charging is still charging. My Honda spends 99% of its time in a charging mode. ----- You're making up random terms like "passive charge" and "persistant charge" that have absolutely no meaning in the world of electrical engineering.

Charging is charging. Period. And Honda spends roughly 99% of its time charging the battery. *Plenty* of energy to run an electric A/C.



And to repeat myself:
(1) Why would you want the motor to *drag* on the engine if, for example, you're climbing a hill??? You're losing power to the battery, that would be better directed to the wheels, to climb the hill. ----- I'm glad the Honda turns off charging during that situation.

You don't want charging when climbing a hill.

troy
 

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I highly suggest you study Prius closer. Nothing is being lost to the battery-pack when climbing the hill, since it is very very very very common for all of that electricity to be used by the second motor immediately. Not needing to use the battery-pack at all is how the system is able to maintain a higher supply for other uses, like the electric A/C.

And "charging is not charging", just look at how AA batteries charge. You've got overnight chargers and those rapid 15-minute chargers. Clearly, they do not work the same.
 

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"You don't want charging when climbing a hill. "

The Prius ECU will keep the battery in its narrow charge band to maximize life. It will only drain it down if it needs it to power the car (or to a lesser extent the A/C). If at the bottom of the hill I am at very low charge (say, due to long wait at a stoplight with the A/C running), I definitely want the car to charge the batery while I climb the hill!
 

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Discussion Starter #19
If at the bottom of the hill I am at very low charge... I definitely want the car to charge the batery while I climb the hill!
Not me.

I don't want to have *two* drags on my engine:
- overcoming gravity
- the generator

Better to turn off the generator, so *all* the engine's power is used overcoming gravity.

troy
 

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ElectricTroy said:
Better to turn off the generator, so *all* the engine's power is used overcoming gravity.
That's, in theory, definetly the best way to do it. You're going to lose energy on the conversion from ICE -> Generator -> Battery -> Inverter -> accessories that you have to do in the Prius. Since the A/C isn't belt driven off the engine (which is also good, no parasitic drag when it's on), you have to put up with that no matter what you do.

But each setup (HSD or IMA) has it's plusses and minuses. With the new IMA setup they have in the upcoming Civic (I guess it's the 2nd generation), it looks to be a lot more competitive with the 2nd generation HSD that's now in the Prius, Highlander, HX400..
 
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