I'm very skeptical on the energy expenditure here, this does seem to be a fairly energy intensive mode of transport, but I assume the market would balance the price accordingly.
It certainly doesn't seem like the sort of thing that would become a mainstream mode of transport without a big change in the energy market.
According to the 2016 Uber Elevate study, traditional cars achieve about 1 mile/kWh, electric cars about 3 mile/kWh, and electric planes about 2 mile/kWh.
To simplify, one trades roll drag for induced (=lift generating) drag, at higher speeds.
The bigger issues are battery performance (specific energy), and regulation, in my view.
New Zealand does have an absolutely insane amount of wind farms. Even if it's not energy efficient, if it's low emissions in that particular market just by the means of energy, it could be useful.
That being said, energy there is insanely expensive due to asset sales; some of the highest cost in the world.
It certainly doesn't seem like the sort of thing that would become a mainstream mode of transport without a big change in the energy market.