EV efficiency - new record

billvon

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My Leaf got about 3.6 miles per kwhr; my Prius Prime gets about 4.2 miles. But purpose built cars are now hitting over 29 miles per kwhr. And this isn't a trike with a formed canopy and a bunch of solar; this is a four door, four seat vehicle that comes close to being practical (top speed of ~85mph.)


https://electrek.co/2018/12/17/solar-powered-car-breaks-record/#more-81037
 
Yeah.. it's a large velomobile and not a car though, so you can't really compare the two.

But it would be nice if it was legal to build cars more like this. Crash safety regulation really prevents you from experimenting with extreme aerodynamic shapes.
 
Im impressed!

Hubmotors FTW!
 
"Yeah.. it's a large velomobile and not a car though, so you can't really compare the two."

Huh?! It's got four doors, seats four people, has no pedals, and it will hit 85 mph. Not a velomobile by any definition I'm aware of.

Yes, it's light, compared to most modern cars... but not compared to "compact" four passenger cars of 50 years ago (VW bug or Moris Minor)
 
At 794 pounds it is closer to a velomobile than a Beetle...more like the original Fiat 500. But I am all for EVs this size replacing current cars. Our Chevy Bolt, at 3,569 pounds is not close to "sustainable." They don't need expensive high efficiency solar panels, or carbon fiber to be practical. Charging from cheap stationary solar or wind is fine. And an extra 100 pounds from less exotic construction would be offset by the weight saved by removing the panels.

What is needed is a quad class for four wheel "motorcycles" like they have in Europe.
 
OK, it's light, but if you put that much tech into a single seat or tandem velocar with electric boost, it would weigh, at most,250 lbs empty.

I'd agree, the big, heavy typical passenger vehicles on the road today are stupidly wasteful. Light vehicles aren't new, we've done them long before carbon fiber was available.
 
Warren said:
What is needed is a quad class for four wheel "motorcycles" like they have in Europe.

There would be some carnage resulting from vehicles like that sharing the roads with today's gluttonmobiles, guided by today's morons. We need to begin subtracting the offenders at the same time, or earlier.
 
I call bull on this 85mph at 33wh per mile, I get that on my ebike doing only 20mph and using sinewave FOC comm with regen and the whole ride with me is less than 100kg, granted there's some aero and next gen tech gains to be had but to get 500kg close to 30wh per mile at 85mph would need a perfect vacuum its to far ahead of current tech for me to believe it is possible to carry four adults in all weather conditions safely and achieve the goals set out.

Think how much energy a gas guzzler uses to do a mile if we swap to electric we are already alot more efficient just need to tweek that design like we are doing slow evolution steps, I don't fancy jumping in one them cardbiard boxs along a road with lorrys and have computers take control and im a passenger long for the ride, I'd rather peddle thank you and make a day of it get to take in some of the views and air and appreciate the world we live in.
If we slow down the speeds then alot more is possible but the fossil fuel dream is not an eternity it's coming to an end like a trex in a tar pit the time is borrowed now might aswell stop thrashing around and slip away quietly.
 
Ianhill said:
I call bull on this 85mph at 33wh per mile, I get that on my ebike doing only 20mph and using sinewave FOC comm with regen and the whole ride with me is less than 100kg, granted there's some aero and next gen tech gains to be had but to get 500kg close to 30wh per mile at 85mph would need a perfect vacuum its to far ahead of current tech for me to believe it is possible to carry four adults in all weather conditions safely and achieve the goals set out.

Another day I checked lifetime Whm average on my Zero with 27,000 miles, it's at 76. I use it in mixed riding modes, typically 35-45mph, occasionally 55mph, and rarely 65-70. The aerodynamics of a street motorcycle combined with a big tall rider makes be believe 76 watts per mile is way more consumption than what should be possible. Oh, and back to the numbers - that thing is 400kg, and I'm 100+ kg myself :)
 
Your figures are in the ball park of reality, 4 people at 85mph would need 4 of your bikes and travel faster but only use half of what u currently using so there's alot of gains needed 100wh per mile for a family car should be the aim it sounds more reasonable that's still around 4× current gen tech efficiency, weight will be the key and battery tech is the challenge but considering where we stood 20 years ago I believe we are in a good place to progress exponentially with smaller lighter transport that's not thoughtless metal boxes but even then 35wh for 4 people at 85mph is very ambitious to say the least only option at the monent is to lie flat inside an aerofoil in blistering heat more of an endurance challenge that requires lots of engineering rather than a daily driver.
 
The general population will never adopt an EV which offers less comfort or safety than a modern car. Perhaps a bit less range if better charging infrastructure is available but that's debatable.

On the flip side I don't think government regulations should be preventing enthusiasts from buying and using such ultra-efficient vehicles.
 
Ianhill said:
I call bull on this 85mph at 33wh per mile, .....
Odd, ? ..i dont see that claim at all in the article !
I read..
3.25kWh per 100km..
... 85/87 mph max speed,....
and also....." using the same power as a 4 slice toaster at 60 km/h."
Three unconnected statements
So if you can accept it needs 2kW to "cruise" at 40 mph......
And a "4 slice toaster is ?... 2.0 kW. ?.....Suggesting approx 33W/km. !
And of course they wont be carrying 4 guys for that test...maybe one 50 kg "jockey"

Also, current ICEs owe a lot of their excess weight to safety regulations, convenience (power everything) ..and durability,
There are still some ICEs that scale out at ~ 500 kg , !
 
Hillhater said:
Also, current ICEs owe a lot of their excess weight to safety regulations, convenience (power everything) ..and durability,
There are still some ICEs that scale out at ~ 500 kg , !

Voitures sans permis?

Even Japanese kei cars are usually 800-1100kg these days.
 
Hillhater said:
Maybe they could learn from the Brits ...

Really? The Morgan Roadster weighs 940kg. Lotus Elise weighs 866kg and up depending on model. Even the Ariel Atom weighs 612kg, and it doesn't keep off the rain and wind, nor offer any streamlining.

The reliant Robin did weigh about 500kg in its day, though.

[youtube]BSaIv_5-Mho[/youtube]
 
Hillhater said:
Maybe they could learn from the Brits ...

Haha our car industry was the best check out the Austin allegro what a beast.
I had a rover metro with a 1.8vvc engine as used in the mk1 160bhp Elise and that metro weighed 825kgs with nothing but a driver seat, they are death traps in an accident but on the plus side I would beat Merc 3.2 amg all the way to my limiter 145mph.
The metro was good as it shared parts so I could be upgraded with nothing but factory parts to over 200bhp and a 1.8 turbo to get that power but it has the perfect floor pan to cut out and place the leaf guts inside her maybe one day when I'm rich I'll try it.

Chalos my neighbour has a 3 wheeler same colour and model as the pic you shown it's a death trap in so many ways but I do like the charm of it and a bike licence is enough to drive it around at 17 with L plates, I can remember a top gear where some nutter had a Porsche engine in one but I don't Thu k he addressed the steering, there is a drift championship for them and a few mods to make it slide rather than topple.
 
The Sport Lotus Elise weighs 798 kg (1800 lbs)...and still has airbags and power windows, and probably AC and electric power steering, though I can't be sure. A 2018 IC Morgan trike weighs 1200 lbs, with no high tech materials used whatsoever.

Just for comparison, a base model '90 Miata weighed barely over 2000 lbs (35 lbs of which was spare tire and jack) a triumph spitfire weighed 1500 lbs in 1962 (with a cast iron engine and head) a '58 AH sprite was 1450 lbs, and a '55 messerschmitt weighed 507 lbs. Tiny trikes can be very light, even if built of low tech materials, and even two seat four wheel cars can easily weigh well under a ton...if you don't insist on power everything.
 
I think some of the lotus Elise mk1 with the 1.4 engine were just under 700kg, even with just 115bhp they still made a 0-60 dash around 8 seconds just enough to call it sporty and in the 90's it was next level bonded construction.
What we need is a car that has the original mini packaging with modern aero a floorpan battery with composite body bare bones interior with weight savings like i mentioned with fibre optic cables no heavy panoramic roof simple cloth interiors and lightweight basic dashboard but very safety orientated honeycomb designs 3d printed areas to increase strength massively but lower weight in cabin areas that can be sacrificed like behinds door cards etc.
I surprised really with all the levels of investment we have not seen anything revolutionary it's like all the manufacturers are scared to step outside the box just incase they lose track and develop the Sinclair c5 etc.
I really don't think the design stage would be hard or the testing and development there's more than enough shown amongst this forum alone that if we all compiled effort and streamlined the outcome to perfection the only trouble we would face is the same as tesla ramping up production while maintaining tolerances.
 
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