The 66-year-old heir to Britain's throne has often spoken of the need to address climate change and has urged members of the public to cut their carbon footprint.
But last weekend, he instructed the royal helicopter to fly 96 kilometres to his Gloucestershire retreat, Highgrove, to be transported to Windsor Great Park, 109 kilometres away, where he stepped into a Jaguar for the Guards Polo Club, The Independent reported.
"Charles is a serial hypocrite. There is no justification for flying around in helicopters. You're not going to convince a family of four to cut down on car use when a prince is flying around the country by helicopter," said Graham Smith, head of the anti-royalist pressure group Republic.
It is estimated that the four trips racked up 412 air kilometres, yet the Prince could have driven to Windsor and back in 249 kilometres.
More From This Section
It would have taken the royal, who reportedly had no other official engagements, about an hour and 45 minutes each way to travel by car.
A statement released by Clarence House said: "The charitable engagement at Guards Polo Club was fitted into a packed diary at relatively short notice.
"The Prince of Wales carries out over 650 public engagements a year. A number of factors are taken into consideration when deciding which form of travel to use... including security, punctuality and logistics.