Hurricane Sandy - I love my Prius!

Just take the cover off? I was thinking more of a permanent pigtail that you can use without a temp hook up every time you need it. I would think the whole case would have to come out to engineer that but I have never done that so leave this discussion to you. Thank you.

 

Hi Firstflight. Being able to force the battery fan and use it to cool the batteries while the prius is stopped is something I've been thinking about too. When I looked closely at the physical layout of the ducting however, I came to the conclusion that this would merely circulate the same warm air around the back of the hatch area (near where the 12V battery lives) and not exhaust it to the exterior.

In my prius there seems to be a gap in the ducting just before it leads to the exterior vent. This means that the moving air from the duct is not able to force the little seal-flaps at the exterior vent point to open. It instead appears to rely on moving air (from the cars speed) to open those flaps and actually suck the air out! Unfortunately I think this layout will really limit the effectiveness of the battery fan while the Prius is stationary.

If however you are fortunate enough to be operating in a location where security is of no concern, then I think that opening he hatch and removing the under-tray (covering the spare tire) would really give good battery cooling (for both batteries).

 

Yes those flaps take very little effort to push, but I've watched them and they definitely don't open in response to the airflow from the fan. The opening in the duct just before it reaches those exit vents seems to make any positive pressure there essentially zero.

My guess is that they instead rely on a venturi effect (ie negative outside pressure) to open those vent flaps and to provide the actual outflow. My belief is that the small gap in the vent there is to allow warm air from around the 12V battery to also exit via this same effect. That is, both the warm duct air from HV battery plus any warm air from the 12V battery can both mix at that point near the exit, and both be "venturied" to outside. I've studied how this works and I really believe that the designers must have decided that the batteries did not need so much cooling when the Prius is stopped.

Of course the air has to go somewhere, so it will pool in the back there and eventually rise and find it's way back to the vent input at the rear seat. At this point, especially if the windows are partially open, then it will be mixing with cooler air. So there is definitely still a net cooling even when it is stopped, as long as the cabin temperature is maintained at something reasonable.

 

Can you give me a link to them? I haven't found any, thanks.

 

Thanks for the info. The first one is interesting, all of them are more expensive then what we were looking at, your unit, and mine cost about $100. The solar type, which I am aware of ( I have 24 on my roof) are really a different animal, and are not 12 volt.

 

Is it possible to hook up with an uninterrupted power supply (UPS), so that the car engine won't run very long time? using the UPS as an energy buffer?

 

Details at the links below on how to get several thousand watts from the traction battery. I ran mine for 27 hours after Sandy hit, plus two half-day tests in the past. My Prius will run all of my 120 volt circuits and could run my 240 volt stuff with load management (I don't since I have a 12 kw generator). If you keep your eyes open on Ebay you can get the UPS and transformer for about $250 each. One tank of gas will last about 2 1/2 days of constant use - 2 or 3 times that if you go with 12 or 8 hours of run time per day (alternating on-off every couple of hours to keep the fridge cold). Any questions you can email me at [email protected]

Doug's PriUPS
http://www.wind-sun.com/ForumVB/showthread.php?12962-Using-a-Prius-as-a-generator

 

Man, I would love to do this but I’m really cautious about messing with my Prius. Is there any way to make this safer?

 

I'll be interested in reading. If your cost is below ~$500 its a winner.

Fore, alternatively you can tap 1000 watts from the 12 volt system easily and fairly cheaply, although if you want pure sine output you'll spend more than I did to get 4000 watts from the traction battery.

 

yes, quite easy, buy a generator, done!

 

Just wondering how much damage it is to idle a prius for 2 days.

 

I can go all the way in to the terminals and back out in about 45 minutes. Pull the tray out of the trunk, pull the safety cutoff, take out a half-dozen bolts. Full pics and notes in the 2nd link I posted above.