Mile Extenstion

Mile Extenstion

The BMWi3 has an innovative mile extender - a small gas engine that recharges the battery as you go. It would be a good idea to include this as an option for those taking long trips. It could be manually started as you begin a long trip when the battery has depleted 10% and it should be able to extend the range by at least 50%. Again it would be activated manually for long trips.
I know it impugns the ideal of pure electric use, but the bottom line it would be a practical OPTION.

ian | July 25, 2013

If you want the option don't buy a Tesla. That's why there are options. Prius and Volt are also options if you want a gas "range extender".

Brian H | July 25, 2013

The i3's extender doesn't extend much. Or fast.

Iowa92x | July 25, 2013

100 miles Brian, plenty.

Vawlkus | July 26, 2013

When your battery is good for double that plus a reserve?

Hybrids are a waste of time and resources. BMWs entrant is junk just like all the rest.

Brian H | July 26, 2013

Low speed, 80 miles, according to the writeups I've seen.

ian | July 26, 2013

Yup. Write ups I've seen have said it keeps the battery charged just enough to get you somewhere you can charge. It didn't even sound likely it would allow full power.

NumberOne | July 27, 2013

Not happening. There are already products by several manufacturers that do that, but none have a battery only range of more than 80 miles as far as I know, so for them, the gas engine is a must. For Tesla however, there are superchargers. I passed the DE rest stop on Wednesday and there was an S recharging. I got a some coffee, and realized that I had spent enough time there for at least a 50% charge. Taking a break is a good thing. Driving for more than 2-3 hours in one stretch is not healthy because it requires you sit in one position while you are moving. Whether you are a passenger or the driver does not make any difference. (I do it often, but it is not a good habit.) Just my 2 cents!

dortor | July 28, 2013

Hey I wonder if we can take up more of the frunk space and put more fuel it so that the range extender could extend range even more - and then we could add a slightly more powerful motor/generator so that it could keep up with the drain on the battery say @ 70 mph - then we could run both electricity and fuel based systems to maximize the range - of course the downside would be that Tesla would now have to add fuel and electricity to the supercharger stations "for free" - but given that the fuel based generator wouldn't be running that much the fuel needs should be minimal - I wonder if we could design a charging adapter that delivers 400V and 255 AMP + highly volatile fuel all in one safe and easy to use connector - it would also be nice if the generator was a multi-fuel geneator where I could run any fuel of my choice from NG, Propane, Ethanol, Diesel, bio-Diesel and a wide range of other fuel mixes (leaded and unleaded) - of course Tesla would have to update the phone app so you could choose:

a) your fuel type
b) refuel + charge
c) charge only
d) refuel only
e) occupy space for no productive reason other than it's great parking spot

that would be so cool to have a vehicle that had all those options - like the cool car Homer designed on the Simpsons…

oh wait - I just read Tesla's charter as a company:

"Tesla makes the best electric cars and electric powertrains in the world. Tesla technology offers the most efficient path to a sustainable energy future. No hybrids. No hydrogen. No hype."

so it would be beyond stupid to design something like that when it's totally against the fundamental premise of the company and it's stated design goal.

so scratch that - it was a bad idea.

Brian H | July 28, 2013

And nicely elaborated, in all its dumbness. ;)

tes-s | July 30, 2013

Instead of a gasoline/ICE charger for a range extender, how about an extender battery option?

Oh wait - they already did that. They call it the 85kwh option.

Ernesto79 | August 16, 2013

I believe in Tesla. Especially in there model X coming out, with the all wheel drive that has two motors installed. All Tesla has to do is install one of those motors backwards acting as a electric generator. Giving any of their models extended range.

Brian H | August 16, 2013

That displays deep ignorance about many things. The motor runs backwards to slow down and return some energy to the battery. This is not extended range as such, it is an increase in efficiency of energy use.

It's called "regeneration" or regen.

cloroxbb | August 16, 2013


If that were true, then people would have done that already.

Ernesto79 | August 16, 2013

@ Brian H

Yes Brian, but the method your talking about regeneration or regen braking is only good when you let go of the accelerator or apply the brake and in doing so, that's not sufficient power going back to the batteries. What I am purposing is putting a system in place that will charge your Telsa as your hitting 80 mhp in the freeway without letting go the the accelerator. Therefore the faster you go, the bigger the charge. And your right a lot of people do display deep ignorance about many things. Your a perfect example.

@ cloroxbb

Am sure someone knows how to do this. The oil company's have bought off people in one form or another who tried to share their idea for alternate energy. This technology is already applied to wind turbines. A wind turbine is just an electric motor that is spun backwards creating energy. And now that Tesla has created their own unique motor which is small and powerful, they can apply the same concept of a wind turbine. If they can find a way to fuse this idea with there car, it could eliminate the whole pug-in concept.

bent | August 16, 2013

I suggest using the following canned response to the perpetual motion crowd:

What you are proposing is a perpetual motion machine. Perpetual motion is not possible and your proposal will therefore not work.

If you believe that perpetual motion is in fact possible then you should create such a machine and market it. If you are right then you will become a billionaire. Good luck!

The engineers at Tesla Motors do not, to the best of our knowledge, believe that perpetual motion is possible and so they are not going to implement your proposal. You will need to walk this walk yourself.

If you believe there exists a conspiracy to suppress knowledge of perpetual motion then you can safely assume that Tesla Motors is part of this conspiracy and, again, they are not going to implement your proposal. You are going to have to fight The Man yourself and build the machine on your own time.

cloroxbb | August 17, 2013


learn physics, then make your own. Good Luck!!

David70 | August 18, 2013


No generators create energy. They convert existing energy to electricity. Even at that, there are losses. Ditto for clorxbb's comment.

RanjitC | August 22, 2013

Maybe Ernesto would like to put a nuclear power plant in the Frunk. Now that would change matter into energy!