An Auxiliary Power Unit for jets in a spark EV... NOT BAD, LMAO. I'd only need aviation earmuffs to go with them!Porsche wrote: ↑Wed Oct 19, 2022 11:39 amHow about this? We could put a small APU in the hatch. This one is only 2 x 1 x 1 ft (and still overkill):
https://aerospace.honeywell.com/us/en/a ... siness-jet
There'd be plenty of room for a few gallons of jet A or maybe kerosene back there too. If we can trick the car to run while charging, we could make a plug-in serial hybrid with 250+ miles of range. I'm pretty sure turbines are considerably more efficient that ICEs for constant RPM applications. I think I remember reading somewhere about people putting kerosene space heaters in their EVs in extreme northern climes, so why not this?:)
It's not quite the same micro power unit you mentioned, but I had a good laugh imagining this thing might actually produce some thrust out the back of the hatch too! In all seriousness, it's a great idea (using jet fuel / kero) considering the States produce a lot of the lighter fuels.
Considering some other auxiliary power generators, I remember back in 2014 Toyota announced a free piston engine linear generator that had a thermal efficiency around 42%. That news exploded, then imploded into an R&D no-press void just as quicky...
That being said, a UK-based company that sells FPE generators, Libertine did not disappear into obscurity. Heard about them about the same time as Toyota, but they present as a more tangible technology with development platforms.
From reading their press and watching some of their youtube vids, it does seem like they are developing a compact format for micro power and light hybrid vehicles now, with what looks to be a similar footprint as the Honeywell module. In one of their vids, they allude that the small modules could fit between the rear axle of a tricycle scooter you'd find in India, very small if that's the case.
Yeah, I think you're right. I think most hybrids are doing ICE + CVT? An external combustion engine like a Stirling engine would also be a bit more efficient than an ICE. It operates optimally at constant speed applications, while also having the flexibility to run off any heat source. They are usually used to recover the waste heat energy from a gas turbine which is a huge thing in gas-fired power plants and other industrial applications, just not transportation! It's really what's missing in the exhaust stage of all ICE vehicles, that's not even to say that in some cases the ICE could be replaced by an external combustion engine entirely.I'm pretty sure turbines are considerably more efficient that ICEs for constant RPM applications.
The Spark is a tough platform to add additional modules considering how compact it is, but just maybe it could work if the trunk space were fully utilized all the way from under the false floor. You might still get to keep the two rear seats, although I can't vouch for how comfortable they'd be with a genny a few inches from their backs . If you wanted to actually drive that far with a generator running, I'd expect at the very least to isolate the generator area from the cabin with some fire retardant insulation and pipe the exhaust outside.
That makes a lot of sense, especially since the only source of heat for the spark is its PTC heaters.I think I remember reading somewhere about people putting kerosene space heaters in their EVs in extreme northern climes, so why not this?:)
You could pipe in a coolant loop to a plate heat exchanger on the genny (or add ducting and an air blower motor) so batteries and cabin could directly benefit from the waste heat in the front instead of consuming battery power.