It is easy to use energy but not easy to store it, use it wisely or handle it. Batteries are not fuel and fuel is not a battery. The old locomotives have proven that electricity makes a great transmission of power. In fact a mechanical transmission has never been made for trains.
So use fuel wisely and transfer the power to the prop and your problems are solved. It is nice to have a plane donated for research but build your electric system first for the mission to need and then build your aircraft around that purpose if you want success.