A genuinely great idea, Dick. Encouraging the development and participation of electric aircraft with the carrying capacity, endurance and robustness to cover that route would be a very real contribution to technological advancement.
My selfish request is that consideration also be given to participation by pilots of old, oil burning technology in - e.g. a mini race from e.g. Darwin to Melbourne along the same route being flown by the electric aircraft. Maybe the entry requirement for that 'mini race' could be e.g. payment of a sponsorship of at least a specified amount to one of the electric aircraft teams, or into a pool from which the prize money for the winner/place getters of the electric aircraft racers would be paid?