Prius as a power source?

See http://priuschat.com/I-need-power-outside-...ter-t22351.html for a little more reference

Note that the power outlets are fused (combined) at 15A, Which probably doesn't lend itself to a 3000W inverter too well.

It is definately possible to use the prius to power smaller electronics, like a laptop or a fish tank, but i don't think i would want to try to use it to power standard household appliances.

One possible solution would be to add your own fuse connected to the battery to allow higher current draws, but you'd want to check first on the current draw thats allowed between the hybrid battery and the 12V system. unfortunately, i don't have that info here anywhere

 

<div class='quotetop'>QUOTE(MrK @ Jul 25 2006, 02:17 PM) [snapback]292076[/snapback]</div>

MrK,

Try this URL to see a broad-brush description of how somebody else set this up.

http://store.yahoo.com/yhst-6122897076971/priusinverter.html

If you want to pull up to 1500 watts, connect the inverter directly to the 12 volt battery. You sound like you understand that level of current would fry the cigarette lighter socket.

Another site I saw (but can't remember the reference to) suggested that, due to the small size of the Prius 12 volt battery, get another regular-sized car battery connect that in parallel with the existing Prius battery (jumper cables), and run the inverter from that. That's to give you a little more surge capacity, as the Prius 12 v battey is tiny.

I'm not sure I'd pull 1500 W even then. I'm sure I'd never go over that, because of the following.

I'm not a technical guru, but my understanding is that the link between the traction (big) battery and the 12 volt battery has a limit of about 1500 watts. So that limits the rate at which you can steadily pull current out of the 12 volt battery. I'm not sure whether you'd damage anything if you tried to pull more. But yes, as I understand it (read the invertersrus story), you have the story right. Turn the car on, pull power out of the 12 volt, the traction battery will keep the 12 v up, then the engine will automatically cycle to keep the traction battery voltage up. And you have the quietest generator on the block.

If you follow the priuschat thread recommened in another post, be sure to go to the priups site. It's a hoot. And it has a lot of good technical detail. I think that's the guy who explains the 1500 watt limit in steady current draw from the 12v battery. If you want to pull more than 1500 watts, you need to connect to the traction battery directly. DO NOT DO THIS, but the site's hilarous. The guy ended up wih a system that could power his house (like 18kw or so) by connecting the traction battery to a commercial UPS whose lead-acid batteries were shot.

I bought a 1500 watt inverter for my business, and a full size car battery, with exactly this scenario in mind, but haven't ever had to hook it up to the Prius 12 V battery (which, by the way, is in the trunk, right hand side, under a removable plastic panel, and is about the size of a motorcycle battery.) So I can't say firsthand, but the article on invertersrus looked right to me.

 

MrK,

Better also read this:

http://priuschat.com/lofiversion/index.php/t13502.html

Particularly the part about, if you blow the 100-amp fuse on the 12-volt side, the car won't run. That guy seems to have done the correct and cautious thing, which is to put a 60 amp fuse in line with the inverter. If that fellow's correct, then trying to draw 1500 watts may be asking for trouble. I swear I've read people who've drawn more than that, but I believe I'd be cautious about the load.

 

<div class='quotetop'>QUOTE(MrK @ Jul 25 2006, 04:58 PM) [snapback]292179[/snapback]</div>

The 150 amp fuse (not 100, I believe) is in the charging line to the 12v battery (from the Prius HV inverter - actually a DC-DC converter). That's where your power to the external inverter comes from, not the toy 12v battery (which would be discharged and ruined quickly if asked to supply high current). The best reference on this is Bob Wilson's work on using the Prius (2001-2003) as a 1Kw UPS.

http://hiwaay.net/~bzwilson/prius/priups.html

If you want more power you need to connect directly to the traction battery as in:

http://www.priups.com/

by Richard Factor.

Good luck and have spare fuses in your kit.

JeffD

 

I have a 1000 watt modified sine wave inverter hard-wired into my 2001 Prius, and (am at least one) person who added a 60 amp fuse to sacrifice itself before the Prius' 100 amp one blows. You are absolutely dead in the water if Toyota's fuse opens. It is rather costly to replace and must be unbolted under one of the engine compartment fuse boxes. So this is an area to stay away from if at all possible.

Fuses are apparently somewhat tricky because they vary in terms of how fast they open at different levels of overload. ANL fuses (such as I have added) are quite sluggish according to the specs I have seen; this is why I chose a 60 amp which at first appears to be small. This fuse has never blown for me, but I don't use quite as much power as Bob Wilson does for example.

Presumably all inverters of the 1000 watt or so size class have internal fuses but I am somewhat conservative when it comes to the Prius electrical system. When you are pulling big amps from there, don't be also running the headlights, HVAC fan, or any other big 12 volt loads.

If you decide to install a big inverter, make sure its power and ground leads are as short as possible and not smaller than 6 gauge wire. Better still 4 gauge.

 

<div class='quotetop'>QUOTE(MrK @ Jul 25 2006, 03:58 PM) [snapback]292179[/snapback]</div>

I'm not an expert, but the load (watts) depends on both volts and amps. The batteries are being charged to a particular voltage, like you say, but that doesn't control the amps that are being drawn from it, so you can definitely overload the battery draw if you don't limit that aspect with a fuse. This is particularly true for controlling surges, since most equipment needs a momentary blast of power to get started, then keeps running at a lower wattage. And it is in the circuit (from what I've just recently read but it makes sense), since the power comes from the gas, to the ICE to the main traction battery (at intervals) where it's stored. Then from the traction battery thru the DC->DC converter (and the internal 100 amp fuse) to drop it to 12V where it keeps the aux battery charged, which is where you likely have the inverter attached. From the aux battery it also has other paths, to the A/C, lights, stereo, a 15-amp fuse to the cigarette lighter, etc. Add them all up and you better use less than 100 amps, hence the safety measure of using a 60-amp fuse on the inverter. 60 amps * 12v = 720 watts peak. If you make sure you turn off all accessories beforehand, you could probably use a 75 amp fuse (do they sell that size? I haven't shopped for anything that big before) for 900 watts.

Interesting thread.

 

<div class='quotetop'>QUOTE(MrK @ Aug 3 2006, 10:29 AM) [snapback]296929[/snapback]</div>

Maybe. Welcome to the pool.

I've also used Richard's approach and I'm mid-way through the project. You may want to contact him directly for more information about the switching power supplies he used to convert Prius traction battery voltages to the 96 or so volts required by sine-wave UPS systems like the HP/Compaq R3000 XR.

In my case I'm still expermenting with mods to make sure that enough juice is available to the UPS to meet the surge demand from my fridge compressor. More info when I'm happy with the solution, but for now I can verify that I do get sine-wave power from the UPS via the Prius -- well more than you can extract from the low-voltage circuit.

Charlie

 

Update: It works!

I followed the approach suggested by Richard Factor. A version of his "portable Large System A" from www.priups.com is now installed in my basement and cabled to a Prius when needed. It runs my fridge and my furnace fan successfully using clean sine-wave power, so my goals have been met.

My implementation differs from his slightly. Mine's in the house, not in the car. The socket in the Prius has a fuse (rated for DC and for the right voltage.) The modified switching supplies themselves have been wired to DC-rated fuses as well. I used a cheap mechanical transfer panel instead of relying on the UPS load-switching circuitry. And I found I needed to add a couple of big capacitors to buffer the switching supply outputs to meet peak demand when the fridge compressor kicks in.

Hats off to Richard, who was extremely helpful.

Charlie

 

Of course the more conversion steps you put inline, the less
efficient the whole rig is. For possibly the ultimate in klunkiness,
see http://techno-fandom.org/~hobbit/cars/tds-priups/
The folks fortunate enough to have directly 200V-compatible systems
are doing it the right way.
.
_H*

 

Dr. Fusco and I were asking about inverter installations the other day and since then I've been nearly obsessed with the idea.

I've read references to a 150A inline fuse for the 12V DC-DC line to the Prius 12V battery. This 150A reference was then corrected to 100A with cautions not to risk blowing this "system" fuse due to difficulty and resulting high cost of replacement, recommending 60-80A positive terminal inline ANL type fuses.

I was just poking around the 12V battery area and noticed a 120A fuse on the positive terminal for a line out that appears to be for all the car's 12V components. Is this consistent with the 100A system fuse because the little 12V battery provides current draw buffer over 100A?

Does this mean a 100A fuse off the battery to an inverter, say 1250W or so, would be just as "safe" to the Prius system as the 60-80A fuses, especially if I drop a 300A peak draw or higher deep cycle battery in parallel between the Prius battery and inverter?

Am I on the right track? I really don't want to zap my car.

 

<div class='quotetop'>QUOTE(M. Oiseau @ Apr 19 2007, 10:58 AM) [snapback]426034[/snapback]</div>

I don't have any answers myself, but there's some good inverter discussion in this thread:
My Prius is Powering my House
http://priuschat.com/index.php?s=&show...st&p=363152

 

MrK and Megan, thank you for the info.

 

Here is another approach:

http://hiwaay.net/~bzwilson/prius/priups.html

Bob Wilson

 

Another PriUPS goes live!