I'm trying to design an aircraft with long range, and I thought that an electric aircraft with generation would be able to do that. However, I've seen very few of these commercially, and I was wondering why. Is a fully electric aircraft too expensive/ not powerful enough to be feasible, economically or physically? Also, is there possibly a way to generate enough power? An alternator/Magneto combination, perhaps?

I'm trying to design an aircraft with a long range, and I thought that an electric aircraft with a generator powered by the motor would be able to do that. 

However, I've seen very few of these commercially not seen any aircraft that do this, and I was wondering why. 

Is a fully electric aircraft too expensive/ not powerful enough to be feasible, economically or physically? 

Also, is there possibly a way to generate enough power? An alternator/Magneto combination, perhaps?

In an all electric propeller plane, is it possible to use an alternator/magneto combination to keep a battery/motor combination with a full charge during the flight?

I'm trying to design an aircraft with long range, and I thought that an electric aircraft with generation would be able to do that. However, I've seen very few of these commercially, and I was wondering why. Is a fully electric aircraft too expensive/ not powerful enough to be feasible, economically or physically? Also, is there possibly a way to generate enough power? An alternator/Magneto combination, perhaps?