Yep, 50 kw hours of continuous energy producing Prius can do and become life savers !

This begs a home-grown U-tube commercial.

Bob Wilson

The Harvard Press has reported that a few of the residents of Harvard used their Priora (plural of Prius) as emergency generators for their houses when the power went out.

Priora??

BTW, running a freezer?!?

Yeah, snow storm and running the freezer is important. Just get an ice chest, fill it full of snow and leave it outside! (not that I know really how this "snow" stuff works here in San Francisco )

But I tried to run my saltwater reef tank off my prius when a known power outage was coming, didn't work as expected though, the modified sine wave the cheapy inverter I was using wasn't very friendly with pumps.

Anyone know what the size limits of the inverter would be that can be used on the Prius? Even with the car left on to keep the 12 volt battery charged, there must be a limit of how much amperage the car will push out to keep the battery charged.

Running a refrigerator and freezer together is a pretty good load without adding tv and lights.

This does sound like a good emergency system if ever needed. And it costs less to buy a good quality inverter than to buy a generator.

I am confused:

There 2 batteries. The standard small 12V for general electricity needs and the main propulsion pack which I think is over 200V, right? I assume that HSD is mainly concerned with monitoring and charging the much bigger battery pack, right?

So then how can they get any power from the smaller 12V battery? Few years back it might have been Katrina, someone in Florida did this, used Prius as a generator. However I always thought it was the main big battery pack.

Anyway what exactl did they use, the smaller 12V sealed led acid, or the big NiMH pack????

My generator which is around 10hp I think generates 15 kW which is plenty for what is described in the article. Prius engine can certainly generate even more power as Riskey noted.

Still, assuming the engine power NiMH pack, I assumed you'd have to wire the main NiMH pack. If it is 200+ volts, then you'd need something more fancy than a 12V inverter, no?

Yes Bob you are confused.

Yes, but there is a DC-DC converter that maintains the charge of the 12v battery that can safely deliver about 100 amps of 12v power (that's 1200 watts)

Both have been used, the traction battery can deliver significantly more power

10 hp is 7500 watts but since there is some inefficiency, it will deliver less. My 16hp generator is rated at 7500 watts(continuous use).

See: PriUPS-getting electricity FROM your hybrid vehicle for a full discussion.

JeffD

Ooops, that was a typo. I should have said 5 kW instead of 15 kW for generator. Thanks.

Ahhh, didn't know that although makes perfect sense. So one can pull a limited amount of power via 12V terminals albeit using a simpler setup and cheap inverter. Cool

thanks

If I understand jdendenberg's info correctly, a 1200 watt inverter is the maximum a Prius can handle? What kind of amperage would a regular car alternator put out to accomodate the inverters available for as high as 5000 watts. It would seem that no alternator would put out enough power for that capacity. I don't know if any vehicles have 400 plus amp alternators, but the inverters are out there. Do they just run a short time till the battery is low even with the engine running?

Thanks for any understandable explanations.


Terry

While an ice chest and snow sounds easy enough, it doesn't work except for beverages. You can't keep anything colder than freezing. So that side of beef in the chest freezer, along with the all important ice cream, needs to go into the garbage can. And filling a cooler with snow/ice doesn't leave a lot of room for the groceries. You would need way too many coolers.

And what about power outages during a summer thunderstorm? I had one last three days. There wasn't enough ice within 20 miles to keep everybody's drinks cold.

Hey, this is to puzzler's comment on the alternators. I know Ford gives you the option on their Super Duty trucks of going with a higher output single alternator or going for a dual setup that I think is 400 or more

Hi MikeSF,

The waste heat from the freezer helps heat the house. So, its kinda like electric heating. An Ice Chest works great in snow storms, because its below freezing.

In a more typical Ice Storm, the ice storm comes in, lays on 2 inches of ice on the power lines overnight, the power lines fall down, and then the warm front comes in, and its 40 F outside. It still takes days to get the power lines back up. And while this did not happen this year in the NE, its the usual scenario one needs to be prepared for.

Damn. Why didn't I think of that? I'm just a couple of towns over from Harvard and lost my power for 16 hours (I was lucky--other people had it much worse). Of course, I would have no clue how to do it.

i recently hooked up a 1200 watt continuous 2400 max i've seen it run with 1500 to 1600 spikes while welding.... so far my prius has 0 problems. (my 12v battery dies.. but that's just me not replacing it)

i've pulled more power while jump starting other cars... or tractors... my prius "dims out" before blowing anything... my brother once messed up with at 24v jump and tried turning it over while i was charging 12 volts at a time... my cheap cables that were bridging the two 12v batteries almost melted...

however.. i don't recommend abusing your vehicle like i do. I simply want to see what this car can take before something breaks. so far, so good.

its kinda off topic, but a lot of grocery stores, like albertsons (now luckys again) and warehouse stores like smart n final, now sell dry ice..

I'm surprised that these stories still make the news, as using the Prius to provide emergency power has been documented for quite some time. Priuschat electrical guru, Bob Wilson has performed considerable testing with the 12vdc system's ability to produce 1kw of power via an inverter, and he has documented the results:
Prius - UPS Project

Bob's study shows that, the Pruis in "ready" mode but without any draws aside from sustaining itself (that is, not drawing any power for outside purposes), the Prius will use .06 gallons (about 8 fluid ounces) of fuel an hour. When drawing a consistent 1 kw load, the consumpton increases to 0.25 gallons (32 fluid ounces) per hour.

If 17 kw were consumed at .25 gal/kw, then 4.25 gallons would have been consumed to produce the external power. If we allow that "3 days" may have actually been 2½ days = 60 hours, then the Prius would have been "ready" for the remaining 43 hours, consuming .06 gallons of fuel per hour, or an additional 2½ gallons of fuel.

We all know the difficulty in getting a consistent fill-up of the Prius fuel tank, so Mr. Sweeny may have only put 5 gallons back into his tank even though these calculations would indicate a total fuel consumption closer to 6.75 gallons--a35% discrepancy. Still, that's not bad for mainaining one's home for 3 days.

There are folks out there that will remind us that a small 1kw Honda inverter/generator will actually use less fuel over the same period of time. Less, but not much less fuel. Besides, it's kind of fun, showing what your Prius can do...and you don't have to fill the tank as often as you would with the Honda genset.

Has anyone seen Mr. Sweeny's contact information? I'm curious how he intends to use his inverter to pump water. My own inverter doesn't have sufficient oomph to start a 1/2 hp sump pump.

My cold weather testing was in 30-40F, dry weather without significant wind. Part of the equation is heat loss from the vehicles. Also, we don't have a good measure of his energy load.

I've found in actual emergencies that the power drain was less than 800 W. Even less when we went to bed and only the heater and AC were cycling. As for starting a 1/2 hp pump motor, I think the key is to have a surge capability but I don't done a serious analysis, yet.

Having inverter surge power is probably not enough. The 12 VDC battery has to provide the extra energy and the standard battery is a bit small. I have thought about getting one of those 'boom box' capacitors but this is only speculation.

If you'd like to investigate the pump startup problem, I have some suggestions on an instrumentation and load management. Of course the time to test is when there is no power shortage and opportunity to fix any problems.

Bob Wilson

Could you charge an additional high capacity deep cycle battery which is in a fixed location in your garage then run the inverter from that?
This would mean a short 12 volt cable from a plug which could be mounted outside the car, under the bumper for example, then you could run out to pick up supplies for half hour and keep the heater fan running while away. It would also mean your inverter could remain on a shelf outside the car.

What do you think?

Picture a middle aged man in his pajamas, cradling an electric coffee grinder in his arms, tip toeing across an icy driveway to the detached garage. That was me two days ago. An early morning wind storm knocked out electrical power an I didn't have any ground coffee. I suppose I could have found a way to manually grind some, but it was easier and much more fun to carry my grinder out to the Prius. Once again Prius electrical power saves the day.

Tom