HA HA I knew the title would get your attention. Well its sought of true........in the latest top gear magazine the vw group are making an electric version of the audi a1 and a3 with a range of about 130 kms but unlike the mitsubishi mi-ev they can keep driving thanks to a tiny 200cc rotary engine that is basically a high powered alternator/battery charger called a 'range extender'. So this quick and comfy car can drive long distances at an average of 1.8lt/100ks or over 130mpg!!!! I love the simplicity of the aircooled vw's but you've got to admire modern efficiency.

yeah good marketing figures. At the end your 100ks you have used $2.50 of petrol but how much money have you spent on electricity? Why would they use notoriously thirsty rotary engines? Can only assume for high rpms.

The reason for using a rotary engine is to keep it as small as possible. The idea is that in normal urban usage, the engine will never have to kick in, so you don't need it to be a particularly good engine. It just needs to be small to tuck out of the way and leave room for the electric drivetrain, power electronics and batteries. This is also why the petrol engine in the Chevy (and soon to be Holden) Volt is very low-tech. No direct injection, no turbocharging, just a plain old 1.4 litre four cylinder. The engine doesn't need to be sophisticated because the electric motor is supposed to do almost all the work. If you only want to charge batteries with your engine then it only needs to run at one engine speed, like a generator.

I agree with waveman but how did they arrive at those consumption figures?

Im guessing that as the petrol engine is used to charge the batteries, rather than as a hybrid drive system it only needs to run in a finely tuned and efficient rpm/load range. I think the clever engineers at vw would have their reasons for going this route!

Yes
an engine is much more efficient when running at one speed...

just charging a battery... electrics do all the work...

LEE

which means the mpg figure is complete utter marketing bullshit.

Not really, put x amount of gallons in and drive y amount of miles

Interesting thought, If I spin the alternator on my maybach with one does my fuel consumption go up or down?

Fuel consumption figures on these things are completely useless if they dont tell us the cost of plugging it into the wall. Who gives a shit if it gets 130km on $2 worth of petrol if it costs $20 to recharge it when I get home. Who gives a shit if it has near zero emissions coming out the back if its burnt enough coal to out-CO2 a top fueller?

Throw in a couple of ahhh bras to make it worth my while at least.

Would be awesome if solar panel and wind farm generated energy recharged the batteries though - then I reckon you'd be on your way. I am so hoping that photovoltaic paint gets commercialised and worthwhile. Coat whatever car/house/bus/truck/train you want in the stuff and let it charge as it's using it, plus store when stationary.

Has anyone got a link with more info? I googled it but couldnt find anything.
Wikipedia hs some good basic readibg regarding efficiencies and ratings for hybrids etc. Good old coal power is the problem it seems still wrt co2.

Whats the life span of the batteries in electric cars? hate to foot the bill for replacement, sorta takes out the savings one would have gained out of going electric, & what about disposing of all these batteries, sorry if I have gone a bit off track cheers Frank

Most manufacturers are generally agreeing that electric vehicle batteries will last roughly 8-10 years. The current replacement cost of an electric vehicles' battery can be $10-15 grand or even more, but in 10 years who knows? By the time your car is ready for a replacement battery pack, may be able to upgrade it to double the range for half the price.

Quote from a well known British motor journalist! I hate the prius so much!!!

"The batteries in your prius, are lithium mined in Canada, turned into a chemical foam in China, and then made into batteries in Japan, put into a car, and then shipped across thousands of miles of ocean"