[TnWesty]

As an early reservation holder (Jan ‘21) and with production estimates being continuously pushed out the Launch Edition (LE) was initially a low point. Having for years driven small, efficient two seaters has been in my genes since the ‘70’s. The Aptera makes sense when almost 100% of my driving is 2 or fewer occupants and less than 300 miles a week. At current gas prices it’s $0.12 to $0.15 per mile just for fuel, but with the Aptera it’s $0.012 per mile before adding the solar charging.

When the LE was announced without DCFC I too revolted but that is old history. Then came the prediction of 5000 LE’s before any options can be added which IMO pushed my early order out to a realistic 2025 or later. Then a potential reality hit: If I have faith, hope, and belief that Aptera will be what it can be then reserve a second, make it a LE, and join the Accelerator program. If it turns out I like it then I will get the second one in maybe 2025 with the configuration I want and keep both or sell the LE. For my driving the Aptera just fits my needs and the Aptera may be the last new car/cars I ever buy.

[TnWesty]

Any thoughts how changing from hand laid honeycomb matting to short length carbon fiber will affect the Aptera’s body from resisting heat transfer? Any increase in heat transfer through the body from interior to exterior (or vice versa) would negatively affect energy usage by heating and air conditioning. Addition insulation could be required by this change in body structure materials. Every design decision has its trade offs. This seams like a late timed decision.

[TnWesty]

I have to claim a seat at the OWG table but not just for the age and color relationship. Raised in the 60s was a cherished experience for me. Raised by military middle class parents who experienced the three mid century wars, we learned respect, god, and country. Life on a military base was a younger set, kids and parents, who had to be responsible.

We learned about cars and how to repair because it was all we could afford. Smaller cars cost less to own, run, maintain, and DIY repair. Why haul 5 empty seats when a two seater leaves more money in your pocket? Cars we have owned include a TR4, Sunbeam Alpine, Spitfire, Civics, Beatle, Accords, CRX, 944, Boxster, Insight gen 1&2, Lotus Europa, Esprit, Westfield Eleven, and Morris Minor Van. There have been family vehicles over the years but those were based on family needs. However an Aptera for me will hopefully fill my final personal car needs. Reliability, drivable, economical, sporty, all weather, and fun is what I want. Quiet, room for some stuff (wife included), Level 2, brisk, and traction control is icing on the cake. Maybe by the end of 2023 I can bring it home.

[TnWesty]

I believe there are two issues when considering charging rates. One previously discussed by Aptera is DC charging limited to a 50KW rate. I understand that DCFC with high ambient temperature and the air conditioning on trying to keep the cabin cool is determining the limit. The issue is no airflow to help dissipate the battery heat and radiant heat capacity is limited under these conditions. Remember the Aptera design is intended to handle weather extremes (typically -40F to +120F).

The other (discussed here) is the Level 2 charging rate. In Level 2 charging you are taking 240VAC and converting it to a DC voltage to charge the battery. The issue will not be the battery heat (though it has to be considered) but with an onboard charger how much heat it produces (the losses) and how the heat is dissipated. Using Quora.com as my reference, it was reported the University of Delaware did a detailed study of a reasonable sample of chargers. They reported the largest losses when charging EV batteries were the onboard chargers and observed an overall efficiency range of 83% to 88%. A study around 2016 at DTU in Denmark found onboard chargers in three EVs ranging from 49% to 77% efficient (DC power to battery out/AC power into the onboard charger).

Using the best efficiency number from the University of Delaware study (88%) and charging at 6.6KW you would have a loss equivalent to about eight 100W light bulbs. That is a lot of heat and how do you remove it from the onboard charger power electronics? I assume you cool the onboard charger by an integral cooling loop or you exhaust a lot of air. The study also reported the lower the SOC and a lower charging rate lowered the efficiency of the charger. The 49% efficiency of a Renault Zoe in Denmark’s study of early EV onboard chargers would take a lot of cooling by any method.

A large onboard charger in a tightly packaged, well insulated space of the Aptera would require integration into the radiant cooling system or significant venting of forced air cooling. The alternative is an external charger of your size choice and appropriate cabling/connectors to your AC source and DC input to the Aptera. One has to ask what is the purpose of the onboard charger and should it fit every need?

[TnWesty]

Add to the list a Lotus Eleven (mine is a Westfield replica). Photos exist of Keith Duckworth sprawled across the hood of an Eleven with Colin Chapman driving down a runway. Keith, an aerodynamicist who designed the body was looking at tuffs of yarn all over the body and checking airflow. At somewhere around 1100 pounds it is a light weight, about 100hp (1098cc), and Stirling Moss drove it over 141 mph around Monza in the late ‘50s.

My list has included past ownership of a Miata, Honda CRX, 1st gen. Insight, 2nd gen. Insight, and a S1 Lotus Europa. Current stable is a Lotus Esprit Turbo and the Westfield Eleven.

Don Z.

[TnWesty]

Elaphe lists the top speed of their M700 motor (Aptera uses this as the basis for the motors) at 1500 RPMs. The tire size used is rotating at 1460 RPMs when doing 100 MPH. I think to go faster you may be into higher voltage, improved insulation, higher frequencies, and number of motor poles. After the first 20,000 sell then Elaphe or Aptera may address a higher motor speed. I would like to see higher potential speed and tracking the Aptera, but at this point hoping for a productive 2022.