Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

World-record electric motor for aircraft (about 260 kW continuous output, only 50 kg)

This site may earn commission on affiliate links.
I can't seem to find the weight of Tesla's motors. Anyone know it to give a comparison between Seimen's and Tesla's?
According to the Siemans site:
The performance of the drive systems used in electric vehicles is about two kW per kg.
That's an interesting quote, as "electric vehicles" can mean anything from a golf cart and a scooter up to a diesel electric locomotive!
 
I think the big difference here is the 260kw continuous output instead of peak output. I don't know what the S's continuous output rating is, but I wouldn't be surprised if its significantly less than 260 kw / 50 kg. Peak output is much more important for cars, while planes are all about continuous output.
 
Another source of power density for automotive electric motors (McLaren on their Formula E motors)

The electric motor that we have developed is incredibly lightweight and powerful. In fact, as far as we know, it has the greatest power density of any automotive electric motor in the world today. A typical series hybrid motor has a power density of 2-3kW/kg. The motor in Formula E delivers a stunning 8kW/kg, which is 3 to 4 times higher.
McLaren - the power behind Formula E
 
Getting the weight of the motor is a nice start, but kWh/lb of batteries is the real killer. Those kW have to come from somewhere :)

For aerospace, the power does not have to come solely from batteries, a jet turbine would work as a generator as well as providing its own thrust. You might have one turbofan driving electrically driven propellers or inducted fans. There would be an efficiency balance between the size and fuel tank of the turbofan, the weight (and size) of the electric motors, and the weight and size of any buffer/ battery pack. For wing based engines, you would have aerodynamic benefits (motor 'hidden in wing'), and also save weight as the wings would be stressed for lighter loads - useful for 'solar' planes as well.

For some purposes (e.g. VTOL), ground or ship based power transmission could be used to augment take off power. Rear tail rotors on helicopters could also use electric motors, rather than shafts from the main engine (not sure if this is already done)
 
Last edited:
I saw this thread and was curious on how this compared to my own experience. The 260kw at 50kg is about 5.2 Kw/kg. In my plane I have a small electric motor, 23kw max, 16kw continuous and about 7.3 lbs. That gives about 2.2 Kw/kg continuous, about half the weight efficiency of the OP. This sailplane has been sold and flown for the past couple of years. Older technology but it works. I've flown it 40 hours over the past two months. Granted it's a recreational type of use in a sailplane but I have fun. Link to motor: http://www.front-electric- sustainer.com/technology.php. Link to my sailplane. AliSport. It's kind of weird for me to drive my electric car 50 miles then fly the electric plane. When I was young I thought that would be science fiction.

  • :smile:

Jim
 
Using ground power for take-off and then regen for landing sounds like a recipe for a very efficient system. I can't imaging how much energy gets wasted by jets when "air braking" on descent. Gotta be a huge number.

Cost and SMOH would make or break this. I agree on the fossil fuel (whether turbine or combustion) as the source of the electricity as the weight of the battery would shoot range to hell. Most bypass turbines don't use thrust as their major propulsion but for transfer to the gear case, so maybe someone can come up with a method of maximizing thrust in the actual charging turbine so that it is ... well ... a hybrid plane.

FAA is going to get paws in this for sure, so they need to increase that SMOH to several thousand hours to even think it to be considered as a choice.

Just my thoughts.