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by ReadTheLicense 1396 days ago
Yes! The same way, using CNG or bio-diesel (for example wood or algae-derived) in plug-in hybrid vehicles with smaller batteries (50 km) would be much more ecological than large battery vehicles.
1 comments

Would they be more efficient? Burning gas is horribly inefficient and has engines have weight as well.
The conversion might not be as efficient but all cars having a 350km battery for the rare occasion when they leave the city 2-3 times a month seems like a bigger waste. They would normally use the 50km battery and the lesser efficiency would kick in only during long distance trips. Modern range extenders can be pretty lightweight... It could even be modular/take-out in your frunk.
>Modern range extenders can be pretty lightweight... It could even be modular/take-out in your frunk.

Not sure how that'd work. To get over 50km range you need a gas engine that provides 100% of the power to the car at highway speeds. A small engine won't pull that off.

Something built for efficiency (think aptera rather than tesla) can cruise indefinitely on a lawnmower motor or a mid range hardware store portable generator.

There are motorbike engines which produce 30kW (double or triple what a tesla needs to cruise) and can be lifted with one hand. Detune it for longevity, efficiency and noise, add a 10-15kW stator and a 10L tank and you can have a range extender which would take up less than half the boot of a sedan.

If we find our collective sanity and allow travelling long distance at 80km/h that halves.

Hell if we could get our act together and design sane sized vehicles with universal standards you could just stop and swap out a pair of 30kg batteries every hour or two.

Swapping batteries is a neat idea. Unfortunately it is a safety risk as you can't know its health.

>>> If we find our collective sanity and allow travelling long distance at 80km/h that halves.

I'd never want to travel 500km at 80km/h. That is nonsense. Also, having 30kW engine in a car on a highway is a life threatening risk, since you cant easily escape dangerous situations (overtaking other vehicles and acceleration at higher speeds takes way too long) - and we're not even talking about so absolutely hip and unnecessary SUVs or a fully loaded car.

> Unfortunately it is a safety risk as you can't know its health.

This is solved by having small batteries where fires can be contained and directed out of the vehicle and by using safer chemistries like LiFePo4.

> I'd never want to travel 500km at 80km/h. That is nonsense.

Just because you don't want to shouldn't mean you get to make everyone everywhere carry around 2-4x as much vehicle and battery as they need just to save 20% trip time.

A status quo where a vehicle can travel at a relatively sane, safe (half the collision energy, and braking distance), and efficient speed without fragile ego'd babies going completely postal because they have to wait 30 seconds to overtake is one where people who don't travel often can live with a vehicle that costs a quarter as much, weighs half as much, produces 1/16th the road wear and uses half the energy.

> Also, having 30kW engine in a car on a highway is a life threatening risk, since you cant easily escape dangerous situations (overtaking other vehicles and acceleration at higher speeds takes way too long) - and we're not even talking about so absolutely hip and unnecessary SUVs or a fully loaded car.

You're not burning 200kW for the whole trip. You'd still have your electric motor and batteries, you only need the average power from your range extender. Or if the base range is 50km, your range extender only needs to provide 3/4 of the energy to give you 2-3 hours of time between charge breaks (which will be short)

That's not true. It needs to recharge a part of the electricity used. For example, if it provides 2/3 of the electricity being used it would potentially triple the range.
Which means it would have to run continuously. Which completely defeats the purpose of having a plug-in hybrid, which is to make most trips using only battery.
Only on long trips!
They are more efficent because they last longer then current battery tech. China has miles of graveyards of green energy veichles. they are environmental hazzards after their useful life and run off rare earth minerals. not sustainable in any sense of the word; other then being an alternative source of fuel.