8/17/09 - A German report on the Aptera

[Matthijs]

vZNs6rWo5bw
Link (http://www.youtube.com/watch?v=vZNs6rWo5bw)

I detect a pickup in interest coming from Germany for the Aptera.

[KarenRei]

Could you offer at least a partial translation for us German-challenged Yankees? :)

[Matthijs]

Could you offer at least a partial translation for us German-challenged Yankees? :)


Ok I will try. My German is not as good as I would like.

"The door opens up and something that resembles an insect drives out. The Aptera 2e. The American electric car looks like a plane where they cutoff the wings, and thats the meaning of the Greek word Aptera, "Wingless Flight". (Ok they got that wrong)
Without a sound both of the Aptera models roll down the sunny streets of California. Despite it's unusual 3 wheel architecture and wide front track, Aptera for the 2e promises excellent handling. In quick cornering the teardrop shaped electro car even looks to be dynamic. The striking shape of the Aptera 2e has a reason, the manufacturer gives a sensational cd of 0.15.
Also worth mentioning is that the Wind scaly egg has a track of 2.24 meter which is very wide, Not necessarily ideal for European city streets. The electric unit of the two seater delivers a torque of 149 Nm. The 360V Lithium-Ion Akku's have a capacity in the art of 22 kilowatt-hours. That way the Aptera 2e can travel up to 160 km and can thereby be the ideal commuter vehicle. Converted to venture into the energetic equivalent of less than 1.2 liters consumed gasoline on 100km. From 0 to 96 km/h that is the equivalent of 60 mph is done in less than 10 seconds. The top speed is limited to 145 km/h. The battery is fully charged in 4 hours. The rear of the front wheel drive 2e leans on one fat wheel. Above this wheel an array of thin led's is situated. A small solar panel on the roof helps to generate power. The from lightweight composite material made 2e weighs just in to 771 kg. To get in you open the scissor style door that move upwards. From the end of 2010 the Aptera will be available in the US. The prices will very based on motor and equipment levels between €14.000 and €28.000. If Aptera will also sell the electro car in Europe is not decided yet.

[Airgetlam]

I believe the appropriate response is "Danke!"

[Matthijs]

I believe the appropriate response is "Danke!"

Bitte! :biggrin:

[KarenRei]

I just watched this again recently, and I noticed at one point Steve talking about the conditions in which the car gets 100 miles range: all accessories on, two passengers, 250 pounds of payload... but the voiceover was talking while Steve said the speed. It was either 65mph or 75mph. Did the voiceover translate the speed? You expect a ~15% difference in per-mile energy consumption between 65 and 75 (from a ~30% difference in aero), so it matters. :)

[Apt3448]

I just watched this again recently, and I noticed at one point Steve talking about the conditions in which the car gets 100 miles range: all accessories on, two passengers, 250 pounds of payload... but the voiceover was talking while Steve said the speed. It was either 65mph or 75mph. Did the voiceover translate the speed? You expect a ~15% difference in per-mile energy consumption between 65 and 75 (from a ~30% difference in aero), so it matters. :)
You mean the Autobild report?
My translation of the german: "with a single charge one can drive 100 miles. And that is not with slow city driving, but with normal highway speed of about 120 kmh, occupied by two people, 125 kg luggage, running air conditioner, and headlights on"

120 kmh equals 75 mph. :)

[KarenRei]

Thanks!

Wow, that range is going to be *really* conservative for someone who drives with only one person, minimal payload, and knows how to keep their foot off the accelerator (since EV ranges fall so quickly with speed). Can't wait to see how much range I can coax out of it going, say, 40mph down an empty desert road ;)

[Apt3448]

I was wondering if it is possible to guestimate the range in various situations from this. You can probably compute the range at 65 mph under the same parameters (+15%?). But indeed, how about single passenger, little payload and daylight conditions?

[KarenRei]

I'd really need to know the balance of energy losses to give you accuracy. For a very rough approximation, rolling drag will be proportional to 1700 + cargo + passenger count * average passenger weight, rolling drag will be proportional to speed squared, and parasitic losses per mile will be inversely correlated to speed. So if you assume a weighting of 30%/65%/5% for Aptera's stated conditions, and you reduce the rolling mass from 2350lbs to 1900lbs (~81%) and the speed from 75mph to 65mph (75%), you get about 79% as much energy used per mile, meaning about 127 miles range.

Honestly, the headlights won't make that much difference. I'm sure Aptera just mentions them because they know people will complain if they're not accounted for. ~120W is pretty dwarfed by the half dozen kilowatts the motor will be eating. Tack on a couple percent range to the above figures. Now, AC should be a relevant power consumer, so if you can operate without it on, that'll be a sizeable boost. Even the EV1's AC, running in its lowest power mode, took 400W. Medium power was 1.2kW and high was 2kW. The 2e has more greenhouse and cabin area than the EV1, but is probably more insulated due to those foam-core composites.

[jstdadd]

Thanks!

Wow, that range is going to be *really* conservative for someone who drives with only one person, minimal payload, and knows how to keep their foot off the accelerator (since EV ranges fall so quickly with speed). Can't wait to see how much range I can coax out of it going, say, 40mph down an empty desert road ;)

In Barstow, in the summer, the air density can be really low. When I took private pilot training several years ago, the topic was mentioned over and over by everyone I met who found that I was a new pilot. You find really long runways all over the desert southwest. Daytime should give you lower drag then nighttime.