Just wondering how much power I could suck out of my 2020 using the 110v outlet in an emergency situation. I'm pretty sure that there is enough amperage to run my furnace ... but for how long? Has anyone done the math for a PHEV with a full tank of gas and a full charge so as to output total kWh? If I knew that number of kWh I could expect I could decide if installing an alternate input into my natural gas furnace would be worthwhile for keeping my house warm in a power failure. BTW, I see that most small gas powered generators seem to be in the 4000 to 6000 watt range, a lot more that I'd get out of the car.
Back of the envelope math:
If PHEV goes 22 miles on 12kWh, and an additional 288 miles on gas as claimed:
22 miles/ 12kWh = 1.8 miles per kWh
288 miles / 1.8 miles per kWh = 160kWh
11.3 gallon tank. Gasoline has 33.7kWh of energy
11.3g * 33.7 = 380kWh of potential energy
160kWh delivered / 380kWh potential = 42% efficient conversion of fuel to energy. (Surprisingly good)
Another forum indicates it takes 3L or .8 gallons to recharge battery to 80%. 9.6kWh from .8 gallons (~44% efficient)
(This is way better than what a small generator can do, about 4-7kWh from 1 gallon, or 12-20% efficient))
So to answer your question: 12kWh battery + 160kWh from full tank of gas = 172 kWh.
Your furnace will draw less than 1.5kw (or it would trip a 15A breaker), so simple math would indicate ~114hrs or 4.7 days.
Given that there will be some fixed loads on the car (Computer, lights, etc) and the fact that the furnace cycles on and off, you may get markedly more or less runtime. For instance, you could likely go for over a week if the furnace is only cycling 2x/hr at 15 min per cycle. Plenty of time to hopefully source more gas.
A refrigerator might use 4kWh per day. A chest freezer might use 10kWh per day.
For reference, my 07 Highlander Hybrid used 4 gallons overnight running its own AC and cycling engine on/off. You'd likely want to use Mountain mode or whatever 'recharge the battery from gas' mode during the day and then use just the battery overnight.