A Tesla Won A Race...

[RedDevil]

And what a race it was... The 24 hours of Oschersleben, open to roadworthy EVs only. Free recharging at 22 kW rate.

https://electrek.co/2018/12/23/tesla...electric-race/

And the winner was ... an original Tesla Roadster!
Helped no doubt by its low profile, low weight and Lotus chassis.
This was the car of which Top Gear said it was no good at the race track, and now it won a 24 hour race.
Rocket boosters?

Of course, limiting the charge rate to 22kW meant cars spent almost as much time recharging as driving round the track. Nor did anyone drive particularly fast.
As if a bunch of ecomodders were going round

[oil pan 4]

The best ones by far were built on lotus bodies.

Wasn't some one trying to convince us that "weigh doesn't really matter on an electric" not that long ago?
(I know it was not you red devil)

[Vman455]

Originally Posted by oil pan 4

The best ones by far were built on lotus bodies.

Wasn't some one trying to convince us that "weigh doesn't really matter on an electric" not that long ago?
(I know it was not you red devil)

That was aerohead, I think, in the "100 MPGe at 100 mph" thread. He mentioned a paper by someone at Volvo, but I couldn't find it anywhere. My search did, however, turn up several academic papers on the optimization of lightweighting and cost in electric vehicles, and all those papers demonstrate increasing efficiency with weight reduction. Power is the integral of the force curve, and force required to move the car is always reduced if the car is lighter. While you get some of that back with regenerative braking, each conversion of energy comes with losses. So while you can get more back from braking in a heavier car, you don't get as much back as you expended moving that heavier car in the first place.

[oil pan 4]

That's what I thoight.

[redpoint5]

22kW is atrocious. I calculated the sweet spot for speed in a Chevy Bolt at ~75 MPH if you have access to a 45 kW charger in exactly the spot you need it (near empty). Much faster and it wastes energy faster than it can be replaced by a charger. I'd assume this race was slower than 75 MPH, since the slower charger wouldn't be able to replace the energy as fast.

[RedDevil]

Yes, 22 kW is bad. Many people entered the race with a Model S, only to find a full charge between stints takes 4 hours. The track has a 1 MW connection so 20 cars could charge at the same time without suffering a reduction in charge rate.

Weight does not matter much on the highway. It does on a race track. Even if you average 75 km/h (45 mph) including charging...

But it was funny the Roadster took it. Then, it may well be the lightest roadworthy EV around.

[oil pan 4]

22kw slow?
Ha, try 2.9 or 3.8kw.
Now my 7 to 8kw portable chademo seems fast.

[RedDevil]

22 kW is lightning fast for home charging. It is slow when on the move; fast chargers are way faster than that.

It is bizarre for racing purposes. It turns the whole event into an economy run. Which was one of my reasons for posting about it

[oil pan 4]

I have a circuit to the garage that can handle 22kw.

For most people a 22kw home unit isn't really affordable, between the cost of the unit it's self, wiring it in, the cost of a service upgrade, ect.

[wdb]

I suspect some may be missing the objective of the race; to combine "range optimization, speed, and charging time" in such a way as to complete the most possible laps in 24 hours. 22KW is just a parameter in the equation.