WCXX

"I didn't expect to be in this world but I think it's kind of cool. For a long time pop has been this laughable, shameful thing. But it's actually gratifying and fun and can unite populations, which I think is incredibly powerful. So hopefully I am showing that pop can be taken seriously."

When we meet, O'Connor, who turned 17 on Thursday, can barely sit upright. "I came down with a kidney infection just as I was about to get on a plane here," she says. "They took me into hospital and put me on a drip and now I'm on heavy-duty antibiotics." With her gothically pale skin offset by dark crimson lips, black-rimmed wide-set eyes and waist-length, mahogany curls, she could hardly be more different from the cute, smiling Lolita teenage princesses who have come before her. She looks much older than she is, a perception reinforced by the deep, commanding timbre of her sonorous voice.

O'Connor's success in Britain comes only weeks after her 28-year-old compatriot Eleanor Catton became the youngest ever winner of the Booker prize. It's quite a wake-up call for those of us who had assumed that modern New Zealand culture didn't stretch far beyond Hobbits, Crowded House and Jane Campion. Is something in the water in Auckland at the moment producing these freakishly talented young women, I ask. She laughs, "It is a little bit weird. Ellie is so talented. I loved her first novel that came out when she was 22, it was so beautiful." She goes on, "I think maybe it is that we are just so far away. Growing up, I was like, I want to do something and get out of here. I love New Zealand, and going back there now that I have travelled, I appreciate it more. But as a teenager growing up in Auckland, I was like, '---- this.'"

On stage the previous night, O'Connor had betrayed no sign of her illness, or that she had only 20 live performances under her belt. While in photographs and videos she adopts the withering, unflinching glare of Kristen Stewart, star of the Twilight films, in performance O'Connor has a goofy theatricality: one minute she is indulging in Stevie Nicks-style witchy, closed-eyed singing, shaking her hair and flicking her hands out; the next, she's all broad smiles and wisecracks, jokily heckling her audience.

^{Lorde performs at the VEVO Halloween showcase at The Oval Space on October 31, 2013 (Gareth Cattermole/Getty Images)}

Yet when she is not being Lorde, O'Connor is clearly a much quieter, more introspective character who could have easily taken a more literary path in life. The second-eldest of four children, O'Connor grew up in the North Shore area of Auckland. Her father is a civil engineer and her mother, Sonja Yelich, a published poet who encouraged her daughter's bookish tendencies. At age 12, O'Connor was reading Raymond Carver; by 14, she was editing her mother's masters thesis. "Mum always made sure there were lots of books around. For a long time we had a TV but no DVD player. Then Mum got one but she only allowed us to watch old stuff like Wonder Woman, The Partridge Family and Little House on the Prairie… Those shows are so cool."

From an early age, O'Connor demonstrated that distinctive confidence in her own tastes. "Mum tried to get me into poetry but I wasn't into it," she says. "I read a lot of short fiction and that has much more common ground with lyrics." At age five, she followed her friend into a drama group and discovered a love of singing and acting. "There is something kind of magic and sacred about performance," she says. "I had to switch on a different side to myself and become a different me."

O'Connor broke into the pop business through a combination of old-fashioned talent spotting and modern marketing techniques. Her friend's father saw her, at age 12, performing cover versions of Duffy's Warwick Avenue and Pixie Lott's Mama Do in a school talent contest, and was so taken by her voice that he sent out tapes of her singing that arrived in the hands of a Universal talent scout. "It was a strange thing for me to launch myself into the spotlight," she says. "I had always been the shy, bookish girl."

Universal put O'Connor together with 30-year-old former punk pop musician Joel Little to translate her haunting vocals into more fully formed songs. The pair would meet over weekends and school holidays, when O'Connor would marry her love of old-fashioned pop harmonies with a growing taste for more underground electronic artists such as Animal Collective and Mercury winner James Blake. Little supplied the propulsive, sparse beats.

''Songwriting is so weird because you are writing down intimate things and then you go into a studio with someone you have never met, who in Joel's case was twice my age and from a different background," she says. "But it was a strange situation where something just clicked. He was very good at being perceptive and figuring out what I do, which is quite a raw, impulsive thing."

Over four years, from 2009, the pair came up with the 10 songs for her debut album, but O'Connor says it never crossed her mind that one might become a worldwide hit. She insisted her first songs be put out on free streaming service SoundCloud without any videos or photographs to promote them."I didn't see my music as number-one Billboard chart selling music," she says. "I tried to market my music the way my favourite indie producers did."

Lorde - Tennis Court on MUZU.TV.

While other mainstream pop acts such as Katy Perry and Britney Spears turn to the same small pool of producers in London, Stockholm and LA who deal in radio-friendly generic dance styles, more-experimental acts such as Kanye West or Lady Gaga opt for complicated, baroque compositions. By contrast, O'Connor's sound is simple yet cinematic, spinning tales of real teenage dreams – penniless but happy nights out full of longing and loneliness – that reject clichés of mindless fun and decadence.

"From the beginning, I have written about and for my peers and friends. It is a unifying thing, a call to arms," she says. "You never hear people making generalisations about adults, yet everyone will make them about teenagers. People forget that we are human beings and that we think differently from each other."

Her thoughtful take on teenage life is a million miles from the histrionic show-off tactics of Miley Cyrus, the young American singer who drew criticism for posing naked in her latest video. O'Connor is a self-professed feminist who has attacked the pernicious effect of Photoshop culture on young girls' self-esteem, but she insists that she isn't purposefully setting herself up as an anti-Cyrus figure. "That is definitely an older person's reaction to my songs," she says. "I would absolutely take my clothes off if I wanted to and that would be my choice and I would be empowered by it."

If teenage stardom can seem like a guaranteed ticket into adult excess, O'Connor, with her concerned mother waiting outside our interview, possesses a maturity that is, for now, inoculating her from the madness growing around her. "What I am doing now, I am learning so much that I couldn't learn at any university at any age," she says. "Every time I get on stage I learn something new. I'm evolving all the time. My next record could sound completely different."

Lorde's album, Pure Heroine, is released by Virgin EMI