I've been looking into various flying technologies and possible energy sources that may power the flight of the island. While the design does not have to be necessarily possible in the real world, it is worth exploring in order to ensure a degree of believability to the design as a whole.
Initial thoughts include a combination of two systems running through the house and island, one providing lift (such as hot air balloon) and the other forward momentum (propellers). Ideally, the effect will not be something too sci-fi or necessarily steampunk, but rather to capture a whimsical element to the design as a whole.
It is worth noting that the flying island is meant to be designed and built by the protagonist, leading to a self assembled aesthetic.
A common theme for flight and renewable energy is with propellers and turbines to harness the power of the wind. As such, these could be present around the house/island as a means to collect energy or provide lift.
A typical turbine with a straightforward ring that more than doubles the output power.
Spiral turbine design
A helix type design
A turbine that floats in the air to maximise the air flow at higher altitudes. More details on this intriguing design can be found here and here.
Interesting shape of turbine that can turn in the wind
As well as a more lo-fi version
Integrating the flight system with the house and island as a whole will be a key factor in this project, and as such I will be making sure to dedicate time to this aspect to ensure that the design is right.