I guess your 20 kilowatts are the power output from the baterrie? I am talking about the measured motor power which makes sense. example. a motor delivers 10 kilowatts of shaft power to a test bench. has an efficiency of 90% then the power output from the battery is around 11 kilowatts.
as soon as a motor is heavily overloaded. it is pretty much the same for all of them, no matter which brand, the efficiency drops extremely.
example. the motor is operated with 14 kilowatts of output power and has an efficiency of approx. 80% which is very realistic with a 4 kilogram motor the power consumption from the battery is around 14 kilowatts + 3 kilowatts loss = 17 kilowatts. at 15 kilowatts and 75% efficiency, for example, 15 kilowatts + 3.75 loss = 18.75 kilowatts are taken from the battery.
these figures are only approximate. In reality, the difference between the real power and the power drawn from the battery is even greater because the more the motor is overloaded, the more losses the esc generates.
if you don’t have an electronic test bench with a generator, you can simply test yourself what power a motor actually gives the propeller. you just have to use the propeller’s power diagram. here you can see the required power at a certain speed.
if you now test your eppg you can see exactly how many more kilowatts of the batterrie are needed to achieve this when you bring the propeller to the specific speed. that is then the loss that arises. of course you have to temp. adhere to the air, air pressure etc.
that are also specified in the propeller diagram. all of this is completely unimportant for many eppg pilots. it affects more the people who deal with development and concept creation.
I hope it’s roughly understandable.
it’s not about evaluating a brand of motor or who is better. it is simply a matter of facts about the current state of the art at eppg motors.