Considering the risks, dangers, and environmental harms of electric vehicles, especially battery-based EVs, I've been thinking about compressed-air (pneumatic) cars. In its most basic form, it seems like a no-brainer, although it has its drawbacks too. The basic idea is pretty simple: a tank of compressed air gets some pressure relieved via the accelerator pedal, and that air spins a turbine, turning the wheels. Cursory research into the subject has revealed a few holes in the plan, though.
So my idea includes two parts: the car itself and its fueling unit. The car itself, I think, is where most of the innovation will come in. The pump would include a large tank, a hose, and a pair of passive compressors: one solar1 and one wind2, both of which are more efficient than electric (it cuts out the middle-man, if you will).
I didn't really think they'd have a heat problem but I guess it makes sense? I have some canned air for cleaning and the can gets pretty cold after just a minute of using it. So I'm not sure why pneumatic cars seem to have a heat problem while in use instead of a freezing problem. But nevertheless, this is a big section of the Wikipedia article, and it looks to be an unsolved problem.
One concern I came up with was, should there be a limit to how much can come out at once? The thought is that I don't want it to just empty the entire tank immediately if you put pedal to the metal, and I don't want it to go TOO fast or break components either. I think you could probably experiment to find the right amount and put a limiter on it.
Another concern I have is how long it can go on one full tank. I'm really not sure, it seems like you'd be able to run out pretty quickly if you put pedal to the metal, and that's not desirable.
There's also the potential for the pressurized vessel to somehow get punctured or crumpled and it explodes. Or is there another way to prevent an explosion in an accident?
Speaking of the pressurized vessel, I think there should be some way, probably inside the car's tank, to reduce the space the compressed air is in so that it has a consistent pressure when it comes out. That way you have a predictable output, most of the time. Maybe this isn't necessary and it already comes out at a consistent rate? Feathering the throttle when it's at full shouldn't send you flying.
The car would also have its own built-in passive wind compressor, but it would be folded in normally to help with aerodynamics. And while it should operate just fine without electricity, it'll probably include a battery, mostly for accessories, radios, lights, anti-theft, and other mechanics. Maybe make it rechargeable and have it either double as a BEV or have the battery help compress some air.
Oh or maybe the passive wind compressor is in the grill instead? So as you drive, some of the air gets captured and is recompressed? The injection points (for the main fueling point and for this) would have to be all before the throttle valve.
If it were my design, I'd want it to have analog gauges on the dash and a screen there that can show the same data. That screen would be used mostly in case the analog gauges don't work, or to display directions, hints (i.e. speed limits), and notices (i.e. doors are open). And for the radio, a standard 2-DIN radio of some kind, so you could easily switch it out for a different one if you want (and that size supports Android Auto and CarPlay). LED headlights but like the line ones that come with every new car these days, instead of the blinding aftermarket ones idiots put in halogen housing.
I totally want to Hacksmith one of these together but it would cost more than I have for just the tires alone, I think. And then there's all the parts, including the tanks, and whatever kind of frame I'd use (maybe I go find a broken down ICE car in a junkyard somewhere, gut it, and build it in that). And then it would probably be illegal to drive because it's got to get certified and inspected and all that, which would make it difficult to test it as a private citizen, too.
If any company reads this and builds one of these, for the love of God don't try to make it look futuristic. Maybe make it retro instead, put some fins on it or something. And make it small but still sturdy -- maybe make it look like a Mustang.
I feel like the few problems with compressed air are imminently solvable, if only we put in the effort (and money) needed to R&D and finally put these on the market in, maybe, 10 years. (EU, you know what to do.)
