Prince Charles made an 80-mile trip by private helicopter over the weekend, just days after he encouraged the public to turn off their lights as part of a global campaign to save energy.
Last Friday, Prince Charles urged people to turn off their lights for Earth Hour between 8:30pm and 9:30pm on Saturday.
Some 700 landmarks across the world went dark to mark the occasion, including Buckingham Palace, London's Tower Bridge, Old Trafford football stadium and Big Ben.
But on Sunday, the heir to the throne and Camilla, the Duchess of Cornwall, were flown almost 80 miles in the Queen’s helicopter from Highgrove, Gloucestershire to Ascot, Berkshire, where the couple watched the Prince's Countryside Fund Raceday.
It is estimated that the Sikorsky S76C aircraft burned 1.3 tons of carbon during the trip, The Mirror reported.
In the video message released on Friday, Charles urged people to observe Earth Hour “not just for ourselves but also for our children and grandchildren”.
“Ladies and gentlemen, Earth Hour is exactly what it says it is. One hour for the whole world to think about this extraordinary planet that sustains us all.
"It is a symbolic and powerful reminder that together we have the power to change things.
He added: "It should also remind us that we do not have much time in which to make those changes.
"If everyone in the world consumed natural resources at the rate we do in the United Kingdom, we would need three planets, not just one, to support us," he said.
Clarence House said in a statement: "Safety, security, the need to minimise disruption for others, time and cost are just some of the factors taken into account when travel decisions are made.
"Clarence House balances out its emissions by investing in sustainable forestry and projects that reduce deforestation."
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