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Comment by NoNameHaveI | Hacker News Reader

Silly question: since a hybrid like a Prius is MEANT to be a generator (of sorts), would an old Prius be a better choice for a stationary generator? Lord knows they are pretty abundant and fairly cheap now. Having lived 5 days without power in the wake of the Iowa derecho in August 2020, I now fully appreciate having an emergency source of electricity. Generators were not to be found, and many were stolen from people's yards, including one from an animal shelter. Gas and ice were hard to come by. Cooking was challenging for us since our stove was electric. My pellet grill was/is electric so we were unable to cook. After 3 days, we had to toss everything from the fridge and freezer.

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https://www.plugoutpower.com/ makes a kit for the Prius (and others) to do just that!

Yes, because it's an Atkinson cycle engine so the engine efficiency is much better, and also because normal car alternators are absurdly inefficient; about 50% or so, I think. The Prius's motor-generator is more like 90%+ efficient.

The Prius's motor-generator might not be able to run at 100% duty cycle, but they're tens of kilowatts max output so you'd need a pretty big load.

Many car alternators also won't run at full load for very long, and can only do about 2kW, so definitely a risk. Either the windings overheat, or the voltage regulator will. They're sometimes thermally regulated, but not always. You can sort of band-aid it with forced cooling to supplement the centrifugal fan on them.

Joey Hess's solar powered fridge system[0] is neat - instead of just storing energy in batteries he uses extra thermal mass[1].

[0] https://fridge0.branchable.com/ [1] https://fridge0.branchable.com/thermal_mass/

I have an 1800 watt 12v inverter in the trunk of my Prius and have pre-wired AMP cables to the battery for easy hookup for any family member not as technically inclined. This is limited, but I was able to run the oil heat and Internet for a few days when a winter storm took out power. The engine only runs when it needs to recharge the hybrid battery, so it is very efficient compare to a standard generator.

You could probably get more power out with a custom inverter tied to the 140v hybrid battery, but this was quick and easy.

I tried to swap in the refrigerator for the heat, but I had grounding issues that was tripping the inverter. Fortunately it was cold out so I was able to manage. Just remember a DR plan isn't done until you have tested it all the way.

If you tapped the traction batteries' output to an inverter there wouldn't be a way for the Prius to realize it wasn't operating normally with its strategy to keep the pack voltage in a ~30%-80% state of charge. It doesn't have a particularly large battery for the traction battery so I'd imagine it would run a lot unless you tie it to a larger pack. There are some folks retrofitting LiFePO4 cells with individual charge controllers to trick the NiMH hybrid system into using them. All the car controls look at is cell voltage.

I believe that the Japanese version of Prius (not sure if the regular one or PHEV) comes from the factory with this option - it can work as a full house generator as long as there is gas in the tank.

If I recall correctly, the prius ICE and EV systems are totally isolated and only connected by the road in between the front and rear tires. The ICE runs the front tires and the EV system is hooked up to the rear tires. You mostly charge the battery up by slowing the car down with the rear tires, so you'd need to modify the car with some belts or linkage between the front and rear drives.

In Toyota's hybrid synergy drive, the electric motor system is inputting to the same transmission as the ICE engine, and is an integral part of the casing. You can see a cutaway of it here to get an idea of what it looks like in practice: https://en.wikipedia.org/wiki/Hybrid_vehicle_drivetrain#/med... What you're describing is indeed how the E-Four system works for the rear wheels on the AWD versions of the Prius

Apparently they can only provide a maximum of three kilowatts of continuous power. Not enough for most folks but better than nothing in an emergency.

Not a budget option now, but this is a factory supported application on properly equipped F-150s. 240v@30A, available on the hybrid or EV only model (IMHO, more useful with the hybrid, cause you can probably drive to get more gas, or store some onsite, where it might be hard to find somewhere to drive to charge)

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