As an electrical generator, it's really not very good. The alternator is rated at 120 Amps (bigger than many, smaller than others).
At 13.8v, that's only 1,656 Watts -- on a good day, with the engine wound up. But the engine won't be wound up. It will instead be idling. The output will be less than 1656 Watts.
It burns right around 0.6 gallons of gasoline per hour (ie 22kW!) while idling and doing ~nothing else. It holds 21 gallons of gas.
So the unachievable best-case of idling-and-doing-no-real-work means that if it starts with a full tank of fuel, it will run out in 35 hours.
And in the real world, it will be doing work since that's the whole point of the exercise. It will therefore use somewhat more than its do-nothing 0.6 gallons per hour idle consumption.
We can ignore the longevity issues of treating a gas-fired vehicle as a stationary generator (these are expensive parts that are getting abnormally heat-soaked) because this is a temporary solution to a temporary problem, but as a practical matter: I'll still need to fill it up with gas, however I do that[1], about every day.
And, sure: That can be a way to solve some problems. With a decent inverter stashed out of the weather, connected with appropriately-big cables, I can probably use it to run the gas-fired furnace, the fridge and freezer, some lights, and some digital entertainment. Maybe it can't run all of that at the same time, but I'm smart and I'll manage.
The gas-fired car probably is useful, as long as I can drive somewhere and fill it back up.
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Or: I could just plug stuff into an appropriate EV. It can sit there quietly being the giant battery that it is, and I can drive it out every couple/three days, or maybe just once per week as some suggest, to fill it back up.
It won't have an idle baseload of anywhere near the equivalent of 0.6 gallons of gasoline and it will therefore respond well to intermittent, dynamic loads like heat and refrigeration.
The EV is probably more-useful, as long as I can drive somewhere and charge it back up.
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[1]: Sure, sure. I can carry a large quantity of gasoline to make the trips more-worthwhile. I can even store some locally (it's a pain to keep it fresh, but do-able).
If I were into that kind of prepping then what would be my practical limit? An extra 40 gallons, for ~60 overall? Great! Now I can run the car/house combo for 3 days before heading back out, and the EV still probably wins on this metric.
[–] dj_gitmo 7 hours ago
[–] ssl-3 6 hours ago
That'd be a great option to explore!
Regular cars are very inefficient at the job. Mine maths out to somewhere around 7% efficiency from fuel-to-electrical-power (and without yet involving the necessary inverter).
But for generating electrical power, PHEVs have very different tricks than a typical-and-pedestrian sleepy belt-driven alternator has.
Any pointers on a candidate model, or range of models, that include this function as a built-in intent?
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I was tempted to get into the maths of using a regular gas-fired car intermittently to charge batteries. Maybe with something like an Anker Solix that has enough surge capacity to start a normal-ish furnace blower or fridge compressor, and can accept ~800W of power from a running car's 12v system for charging and/or output.
The temptation persists to write further about that kind of concept at some point, but the previous comment was getting long-enough that people tend to tune out anyway.
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Except, as an aside: After the 2012 derecho where my neighborhood was without power for a couple of weeks, a neighbor down the block from me parked a minty-looking John Deere tractor in his driveway. This was connected, via PTO, to a rather beefy generator.
That combination (a tractor with a PTO is meant to do stationary-engine duty while doing significant work) sure did look expensive to keep going.
But it was still humming along every time I went past, so it must have been working for him.
(And during that outage, the big corpo gas station just a few blocks further out grew a genset the size of a shipping container that powered their operation. After they got that going, which took a couple of days from the start of the blackout, they were running very normally. IIRC it took them more days to get it disconnected and shut down than to get it delivered and set up, but it worked, and we all had fuel nearby.)