Prince Charles was accused of hypocrisy yesterday after it emerged he made an 80-mile journey by helicopter just days after urging people to save energy by turning off their lights.

The 66-year-old prince and the Duchess of Cornwall flew from Highgrove to an event at Ascot racecourse on Sunday instead of going by car.

Two days before the event – at which Charles was seen laughing at the sight of sheep jumping over fences – he had recorded a video message urging people to switch off their lights in support of Earth Hour.

High life: Prince Charles steps out of the royal helicopter in Purleigh, Essex, after another short journey in January last year

The royal helicopter left its base in Hampshire to take the Prince of Wales to Ascot before returning them home later in the day and flying back to its base. One of Charles's cars could have driven down the M4

Prince Charles (pictured with Camilla at Ascot) made an 80-mile trip by helicopter just days after he urged people to turn off their lights to save energy

It is the latest example of what critics say is his failure to adjust his lifestyle to match his green rhetoric.

The Royal Household’s Sikorsky helicopter flew from its base near Farnborough, Hampshire, to pick the couple up from their Highgrove estate in Gloucestershire. It then flew them to and from Ascot, in Berkshire, to watch The Prince’s Countryside Fund Raceday, before returning to the base – making a total journey of more than 250 miles.

As a result, the trip created over a ton more carbon dioxide – the gas blamed for causing global warming – than if they had travelled there and back in his chauffeur-driven Jaguar.

The 160-mile round trip by road could have used less than four gallons of petrol, whereas the four separate flights would have burnt an estimated 200 gallons of aviation fuel.

Experts said that going by car would have produced around 0.06 tons of carbon dioxide, compared to 1.3 tons for the flights.

Last night pressure group Plane Stupid, which campaigns against unnecessary air travel, called for Prince Charles to change his actions to match his words.

‘Turning off your lights, or even replacing them with energy efficient bulbs, is a drop in the carbon ocean compared to the emissions from flights,’ said activist James Smith.

‘For Charles and every other Briton, flying is our climate Achilles heel as we fly more than any other nation. If you fly more than once a year, the chances are it’s your biggest contribution to wrecking the climate.’

John O’Connell, director of the TaxPayers’ Alliance, said: ‘This is hardly the best use of hard-pressed taxpayers’ money. No area of spending should be off limits when it comes to finding savings, and that includes these unnecessary and energy-intensive extravagances.’

On Friday, Charles had recorded a video message to raise awareness for Earth Hour, an annual global event run by charity the World Wildlife Fund, in which people are encouraged to turn off their lights for one hour to show they care about protecting the environment.

The heir to the throne and Camilla flew by helicopter from Highgrove, Gloucestershire to Ascot, Berkshire on Sunday, it has been emerged

The prince urged people to work to save the planet ‘not just for ourselves but also for our children and grandchildren’.

Describing the event as ‘one hour for the whole world to think about this extraordinary planet that sustains us all’, he added that it was ‘a symbolic and powerful reminder that together we have the power to change things’.

Clarence House declined to comment on his helicopter trip, which they described as a public engagement, but a source said the decision to go by helicopter had been assessed in the same manner as all Royal travel. ‘We have to look at safety and security issues while minimising the disruption caused to others, and time and cost are also factors,’ the source said.

According to Charles’s official website, all his emissions are offset through the Government’s Carbon Offsetting Facility and UK tree-planting initiatives.

His household produces an annual carbon report, which shows his emissions from official UK travel rose by more than a third last year to 470 tonnes – although total emissions, including domestic energy use, were down.

Royal Family has Sikorsky S-76 helicopter operated from Blackbushe Aerodrome in Hampshire. File photo

Courtiers have previously acknowledged that Charles needed to ‘substantially’ curb his reliance on gas-guzzling private planes by taking more trips by car or scheduled train.

The helicopter journey is not the first time Charles has been accused of failing to live up to his own statements that we must do more to protect the environment.

In 2007, he was branded a hypocrite after he flew 20 members of staff to New York in business class to collect an award marking his environmental awareness. He then spent an estimated £1million hiring an Airbus for a tour of Gulf states.

In 1991, he had his Bentley driven 850 miles from England to what was then Czechoslovakia for a tour, despite having recently described cars as ‘monsters’ and ‘voracious beasts’. The epic journey was justified because the car was bomb proof.

And last year, after Charles had written in Country Life magazine that it would be a ‘folly to lose agricultural land’, his Duchy of Cornwall estate allowed 55 acres of farmland near Truro to be developed as a supermarket, housing estate and recycling centre.

Prince Charles had urged people to help the environment by turning off lights for Earth Hour on Friday