Those who live overseas, such as singer Shawn Mendes, will perform virtually, while a fossil fuel-free set from Coldplay will be powered by energy created by 60 cyclists.

The five awards, which will see winners given £1million towards their environmental innovations, will be announced by the Duchess of Cambridge, Dame Emma Thompson, actress and feminist campaigner Emma Watson, actor and producer David Oyelowo and footballer Mo Salah.

Hosted by Clara Amfo and Dermot O’Leary, the event will be introduced by Prince William, with a starring role for Sir David Attenborough, and feature performances from musicians Ed Sheeran, KSI and Yemi Alade.

A royal source said: “The original brief for the set design was that this has to be the most environmentally sustainable production possible. It was ‘not a nice to have’, but essential.

“The Duke has been involved in conversations since day one. For him and all of the team the sustainability has been absolutely imperative.”

The event, at Alexandra Palace in London, will have sets built using recyclable or reusable material, with low-energy or LED lighting.

Nothing new is being bought for the show

All screens have been hired and will be returned for use elsewhere, with nothing new being bought for the show on Sunday, Oct 17.

The BBC staff working on the broadcast have been cycling up the hill to work at Alexandra Palace each day, with everyone on site eating plant-based food.

Canapes served to guests on the night will all be plant-based, with the event planning done on a paperless basis and all the scripts edited and agreed online.

The Duke and Duchess will travel across London from Kensington Palace by car for the evening.

The Duchess of Cambridge is to overcome her nerves about public speaking to present one of the awards: the first time she has taken a significant speaking role at an event broadcast to an audience of millions around the globe.