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2014 Honda CR-V - Inverters

Dear Car Talk:
Here’s a new car topic: Inverters on cars for power outages.
The inverters I am talking about are ones attached to car batteries, I’d rather avoid the cigarette lighter plug-ins for safety.
With all the power outages in California lately, I was able to utilize my motor home’s generator to keep a two fridges & one commercial freezer in proper temperature ranges. But having our motor home is not always convenient for us. So, what about hooking up a sine wave inverter to the car battery for household 110V power?
I realize that the engine needs to run for a period of time to keep the battery from depleting, but just what voltage/wattage can be obtained to stay within the limits of the car battery/alternator without mishap to the car’s electrical system? And just how many appliances can be run at one time with such a generator? I realize that peak wattage is a consideration as well for motor startups.
For instance, a typical a 725-watt refrigerator draws 725/120 = 6 amps.
Any thoughts or suggestions on this?

Thanks,
Tony

A large car alternator puts out about 2100 watts… 14 volts times 160 amps… maximum. At idle, figure about 1800 watts. Losses in the invertor gets it down to 1650 or so.

The battery can not provide that much. Figure 50 amps, or 600 watts for about an hour at best with a big car battery.

You won’t power many home items with a car alternator and invertor.

Hi Tony, I put a 2000 watt inverter on my 2008 Chrysler Pacifica. At 12 volts, that’s a draw of 167 amps. I had a 200 amp Denso alternator, but to make sure I was covered I got in touch with Denso and they confirmed the 200 amps was a continuous rating. At 110 volts that gave me an 18 amp output which was plenty for my needs.