Using the CR-Z as a backup generator

[wizkid057]

So, with this end-of-the-world storm coming (sarcasm!) I figure it's possible to be without power for a bit.

I have a 2000 watt 12VDC to 120VAC inverter that I used with a previous solar electric system and a lead-acid battery pack of roughly 15kWh.

Well, I don't have the battery pack anymore (finally failed after 16 years), but I do have the inverter.

Now, this thing will draw roughly 1 amp per 9.5 watts. So, a 1000 watt microwave will consume ~105 amps at the 12V level. I know for sure that our puny 12V battery can't handle that kind of load for very long, if at all. But if the engine is running and the IMA battery is full, I wonder if the DC-DC converter could push that kind of juice.

Any ideas what our DC-DC converter is rated at? Any other considerations for this?

-wk

[wizkid057]

Well, I called it... power has been out for 6 hours...

So, I have my CR-Z idling with about a 45 amp 12V load on it from a high power DC-AC inverter running some lights and other odds and ends in my house... odds and ends being my laptop, cell phone chargers (for wifi tether since my cable modem won't link up... I assume the local hub is down too...), 40" LCD TV, PS3 (watching some blurays), window A/C unit with just the fan running, speakers, etc.

Been running for about an hour now. Meter shows DC voltage at 12.1 under the load.
I checked the dash gauges and the IMA battery is right where I left it an hour ago at 6/8 blocks. So, at a 45 amp load (540 watts) for 1 hour, the IMA battery would be dead if the engine wasn't supplying the power.) I don't think our puny little 12V battery could have handled this load for that long.

I did um... *try* to fire up my little window A/C unit... the invert can handle it (2000 watts peak... and I've run it at 1800 watts steady) but, the 'Z couldn't supply the juice to get it going. Might be that the run is too long on the DC side to the inverter... I have 2 gauge wire from the battery terminals running to the inside of the house where the inverter sits.









So, we'll see what happens.

[wizkid057]

Well, its now 2PM on the day after, so, 20 hours without power.

Shutdown the CR-Z generator before I went to sleep last night, fired it back up this morning.

I did a better connection job this time and I'm currently drawing just over 60 amps at 12V without breaking a sweat. Was able to fire up my little window A/C unit AND the refrigerator in the kitchen with no problems. I'm pretty impressed.

So, CR-Z has been idling running all of this for about 4 hours now. Dropped 2 bars on the gas gauge since I started this project last night.

Interestingly enough, the voltage is not sagging at all this time. Holding a steady 13.5v even under 60+ amps of 12V load.

Refrigerator was up to 22F in the freezer and 59F in the fridge when I plugged it in. See the pics and its down to 8F and 43F respectively after an hour or so.















Now that it's light out I could get some better pics.

Didnt take a pic of the Kill-A-Watt this time, but, AC draw is just over 625 watts right now, with some peaks over 1000 or so when the A/C kicks off/on.

[CRZCT]

So the hybrid battery still Is maintaining full charge ? I wonder how much fuel you will burn over 8 hours running . I'm jealous of the way the Prius can be used as a generator , must be nice that the motor only starts every half hour or so to recharge .

[wizkid057]

Yeah, it doesn't seem to be touching the IMA battery or the 12V battery with the engine running.

I've got roughly 10 hours of run time now idling and I've only dropped 3 bars of gas from a full tank. At that rate I should get a good few days of idle time out of a full tank.

[wizkid057]

Holy amps, Batman...

So, I peaked out at a steady 120 amps (~1400 watts) before the 12V system on the CR-Z started to really sag. (Down to 10.5v)

Back at a steady draw of about 75 amps with no major sag.



Pretty cool project though. Definitely should research this some more.

[SuiteMike]

MY sister and I were just talking about this how if something happened, how well we could survive, and knowing the CRZ is able to help out as a lil generator is more than comforting =P

[wizkid057]

Seems like just under 75 amps is the limit at idle. Went to about 85 and the voltage started to slowly drop as if the 12V battery was handling some of the load.

[CR-Z.ealot]

Cool posts... thanks for putting them up. If you get the chance, a photo of the inverter's connection to the car would be great.

On a side note, best regards to all members out there who were affected by Irene. Hope you get power back asap.

[Varmint]

Luckily, I have a propane generator for the major appliances in my home. But this is a very good thread. Thanks for posting the details.