A book about climate change written in the form of an extended comic strip would not seem an obvious bestseller. But then along came World Without End.

An unusual collaboration between Jean-Marc Jancovici, a French engineer turned environmental guru, and the graphic artist Christophe Blain, it has sold more than a million copies in its original French version since it was published three years ago, making it the country’s most successful book in 2022. Translations into twenty or so languages including Korean, Chinese, Vietnamese and Portuguese followed — and it is finally coming out in Britain.

The French are known for their love of the bande dessinée— BD for short — with a passion not matched in the English-speaking world. Last year they snapped up 75 million of them — in the UK, by contrast, we bought only 5.7 million. In a recent survey of French book buyers, comics were cited as the fourth most popular genre, behind DIY, lifestyle/leisure and history, but ahead of spy and crime novels. They are considered an art form and certainly not just for kids.

Jean-Marc Jancovici, left, and Christophe Blain, the creators of World Without End.

The field is dominated by fiction: last year’s bestseller list was headed by Asterix, the doughty Gaul who is still going strong 65 years after he first appeared in a magazine. Asterix and the White Iris, his 40th adventure, has sold more than 1.6 million copies in France alone. Perhaps it is because of Asterix, which almost every French child enjoys in their youth, that the French continue to read comics through adulthood. And some of them are very, well, adult. There is no shortage of bandes dessinées érotiques, including Les aventures de Jodelle, a 1966 Asterix-inspired sexual satire drawn in pop art style by Guy Peellaert and scripted by Pierre Bartier, and Guido Crepax’s Story of O, a 1975 comic adaptation of Pauline Reage’s original.

More serious real-life subjects have been given the same treatment. This month there appeared a BD about Grégory Villemin, a four-year-old whose murder in 1984 remains one of France’s most notorious cold cases, and there is also a comic book series based on Yuval Noah Harari’s Sapiens (which, judging by its Amazon rankings, is outselling the original).

A page from Asterix and the Goths, a series that almost every French child reads.

But none of the non-fiction strips has done as well as World Without End. The book is not just about climate change, but also the role played by energy in the development of mankind. Jancovici, 62, explains this when we meet in the office of Carbone 4, his consulting and training company in Paris. At its heart is a simple observation: “Like all animals, humans are lazy and accumulative.”

There is already plenty of stuff available on climate change,” he says. “My aim was to explain the role of fossil fuels in framing the modern world and why it is therefore so hard to do without them.” It is these fuels that power the plethora of machines at home and, thanks to globalization, abroad that allow us to live far better than our ancestors did, albeit less sustainably.

It is a subject that Jancovici, an affable bundle of energy himself, has already tackled in previous articles, books and talks. One of those talks, uploaded on YouTube, caught the attention of Blain, 54, a respected name in the world of the bande dessinée.

Not for kids: one of France’s beloved bandes dessinées érotiques, The Adventures of Jodelle.

The two men met in a café and hit it off. Such is the artist’s renown that when Jancovici mentioned the idea to his publisher they went for it immediately. Blain has form: although he has drawn a number of fictional works, he has also turned his hand to more serious stuff.

One of his more unusual successes was Quai d’Orsay. Taking its name from the home of the French foreign ministry, the two-volume series describes, in fictionalized form, the battle waged in the early 2000s by Dominique de Villepin, its boss at the time, to prevent his country from being dragged into George W Bush’s war on Iraq. It, too, was a bestseller — something unimaginable anywhere but France — and later appeared in English as Weapons of Mass Diplomacy.

Thanks to Blain’s skills, World Without End turns out to be a surprisingly good way of conveying in a single frame complicated notions that would take paragraphs to explain in a conventional book. The average human, we are told, consumes 22,000 kWh of energy a year. “It’s as if each person on Earth had roughly 200 slaves working for them all the time,” says one caption accompanying a drawing of a Roman, relaxing on a couch in a pillared hall.

An image from World Without End, one of France’s most successful books of the decade.

Another frame shows a man lying in a bath of black liquid, a toy plane in his hand. “A round trip from Paris to New York is a big tub of oil,” reads the caption. “That’s 300-350 litres per passenger, almost the annual consumption of a European who drives a small car every day.”

Jancovici is skeptical that salvation will come from renewables alone. Like a growing number of environmentalists, he believes that our quest for carbon neutral sources of power must necessarily lead to nuclear power — which has risks he sees as overblown.

“Nuclear power is a bit like air travel. Accidents are attention-grabbing and create a sense of dread,” says a cartoon version of Jancovici, whose dialogue with a cartoon Blain punctuates the book. “The authorities pander to an inordinate fear of nuclear power rooted in a lack of understanding.”

Provocative? Maybe. But who says a comic book can’t challenge you and make you think as well as make you smile?

Jancovici as portrayed by Blain.

Given the time and resources needed to build power stations, nuclear alone is not the solution. The book’s message is that we must also make changes to the way we live, which are going to be serious and potentially uncomfortable.

“Making significant energy savings has nothing to do with turning off the lights or using recyclable coffee cups,” the book claims. It is instead about “all the things we buy during the year, how we get around, what we eat, the size of the house we live in and its heating”.

I ask Jancovici if he leads by example. When did he last take a plane? For leisure, in 1993, although he did fly for professional reasons to China in 2015 and Morocco in 2018. But he will not do so again, which has made it difficult to travel to promote all those foreign-language versions of the book. His shirt? Bought seven or eight years ago; the suit jacket hanging on the back of his chair is 20 years old. “I belong to that group of men who hate buying anything,” he says.

He still eats meat and dairy products, but not as many as he used to. I am surprised to learn that he and his family have a car, and a diesel one at that. But at least it is ten years old and he never drives except sometimes when they go on holiday.

Jancovici is clearly gratified by the book’s vast success, which has sold many more copies than his previous conventional works, which relied on words alone to convey his message. It remains to be seen whether the French passion for comics will spread across the Channel, but first I have my own travel sins to atone for. Should I feel guilty about my lifestyle, which relies on rather a lot of flights, I ask before I leave. “It is a problem between you and your soul,” Jancovici says, laughing.

Peter Conradi is the Europe editor at The Sunday Times