Ananova:

Prince Charles delivered a speech on the environment to the world's leaders as a hologram before vanishing into thin air.

A life-size, 3D image of the Prince was projected onto the stage of the World Future Energy Summit in Abu Dhabi.

The Prince was reluctant to attend the summit in person because the flights for him and his entourage would have generated an estimated 20 tons of carbon waste.

In comparison the hologram is thought to have left a carbon footprint equivalent to a lightbulb, reports the Daily Telegraph.

Prince Charles' six-minute speech was pre-recorded in the drawing room of Clarence House and transferred into a 3D image.

Sean Reel, Commercial Director for Connecta Group, which produced the image, said: "He was keen on using the hologram to show his commitment to reducing the carbon footprint.

"He is walking back and forth and gesturing with his hands. It looks as though he is right there."

It meant that the Prince could be seen in two places at the same time - in Abu Dhabi and visiting a former colliery in Ayrshire.