Idris Elba has shared details of his “dream” to turn an island off the coast of Sierra Leone, the country where his father was born, into an environmentally friendly smart city.

The actor is working with his childhood friend to develop Sherbro, which is roughly the size of the Isle of Man, after the island was given enough autonomy by the west African nation’s government to allow the work to go ahead.

“Originally, we went there thinking how could we bring tourism to the most incredible 19 miles of beachfront,” Elba told the BBC. But his friend Siaka Stevens said it became apparent Sierra Leone was not yet prepared for such an influx of tourists.

Sherbro Island. Photograph: Nick Ledger/Alamy

Instead, the pair – who grew up together in east London – decided to embark on a more ambitious project. Their company, Sherbro Alliance Partners (SAP), has reached agreements with the Sierra Leonean government, as well as several major firms, to build an eco city as a public-private partnership.

They have agreed a deal with the energy company Octopus to build Sierra Leone’s first windfarm on the island, which lacks mains electricity and is a two-hour ferry trip from the mainland. Elba said a sustainable approach to developing the project would be central throughout the development.

Equally important will be respecting local culture and sensibilities, with Elba expressing his hope to create a “culturally diverse international city that blends African tradition, dynamism, and pride with state-of-the-art infrastructure and services”.

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