Prince Harry and Meghan Markle faced another embarrassing situation after their not-so-eco-friendly lifestyle has been revealed. 

In a survey created by Save on Energy, it ranked members of the royal family based on six key environmental features. 

Using points systems, the royals were evaluated through their contributions on travel footprint, ecological engagements, links to environmental charities, sustainable fashion, social media involvement surrounding ecological issues, and lastly, electric car ownership. 

The Prince of Wales Named as Most Eco-Friendly Royal

Prince Charles topped the list and was named the most eco-friendly royal with 156 points. 

As cited by the energy company, the heir to the throne has been a vocal supporter of sustainable causes and advocate of various environmental campaigns through his engagements and social media presence. 

Meanwhile, Duchess Camilla landed on the second spot with an overall score of 84 eco-points, while the third rank belonged to Prince Philip with 44 points. 

Kate Middleton and Queen Elizabeth II landed on the fourth and fifth spots with 29 and 23 points, respectively. 

On the other hand, Prince William got the sixth spot, as he and Duchess Kate were commended for their "keen" social media engagements regarding ecological issues.

Prince Harry and Meghan Markle Dubbed as the Least Eco-Friendly Royals

Unfortunately, the Duke and Duchess of Sussex received the lowest survey score and were named the least eco-friendly royals. 

With only nine points each, the company explained that although the former "Suits" star supports eco-conscious brands, the couple has less "environmental charities and engagements" as compared to the other senior royals. 

"Despite having been awarded points for owning an electric car and Meghan's loyalty to sustainable fashion brands, Harry and Meghan engaged considerably less than others with environmental charities and engagements between March 2019 and 2020, which hinders their score," the survey stated. 

For what it's worth, Markle has been photographed donning sustainable brands, that includes British fashion designer Stella McCartney, French eco-sneakers Veja and luxury ready-to-wear designer Gabriela Hearst. 

Aside from being the least eco-friendly royals, Save on Energy also mentioned that the Sussexes have "the third-worst carbon footprint of all royals."

As noted by The Sun, Prince Harry and Markle's 10-day royal tour in Southern Africa had almost the same carbon footprint as most Britons emit in an entire year. 

Prince Harry and Meghan Markle on Social and Humanitarian Issues 

It is possible that the reason for the Sussexes' low environmental engagement is because they are more focused on social and humanitarian issues. 

Following their resignation as senior members of the Firm, the couple expressed their wish to carve out more "progressive" roles. 

As the family of three settles in their $14 million mansion located in upscale Montecito, Santa Barbara, the Sussexes have been delivering speeches involving the Black Lives Matter movement and encouraging Americans to participate and exercise their right to vote. 

With this, the couple have been widely criticized by royal experts and Britons for being "too political," even coming to a point when others urged the two to give up their royal titles, 

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