Still watching: The man who brought us 'Big Brother'

Peter Bazalgette tells Matthew Bell that digital is the future. But, shhh, don't mention reality TV

Peter Bazalgette has a knack for good timing. In the Nineties, he invented Changing Rooms, the home-improvement show that spawned a dozen others and brought us Laurence Llewelyn-Bowen . Then he dreamed up Ready Steady Cook and Ground Force, both sold and copied worldwide. His ability to tap into the cultural psyche was proven beyond doubt with his discovery of Big Brother, which he imported to Britain from Holland, giving birth to reality TV.

"It's just telly," he says of his achievements, although he is proud of Changing Rooms. "It struck a profound chord because people are house proud and the thought of somebody coming in and doing it up behind your back is horrifying but compelling."

His finest bit of timing was his departure from television in 2007 when, two months before the credit crunch, he helped to sell Endemol, the production company of which he was worldwide creative director, for€€3.2bn. It's now worth much less, but Big Brother, its most successful show, continues to run in dozens of countries – the 10th UK series kicking off last week.

It might not just have been the cash that spurred Bazalgette to quit. For years he was pilloried as the man responsible for debasing television, named by the Daily Mail as one of the "Ten Worst Britons". His great-great-grandfather, Sir Joseph Bazalgette, designed London's sewage system, so the joke goes that he pumped the lumps out of our homes while the young Baz pumped it all back in.

Big Brother is now firmly in the past for Baz, and he declines to discuss it when we meet for tea around the corner from his stuccoed house in one of Notting Hill's smartest streets. Aged 56, he has the relaxed air of someone who need never work again, although he serves on various boards and writes a column for Prospect. On Tuesday he will speak in a debate hosted by market research firm YouGov Stone, where he's a director, on the question "What's to become of British television?", a subject about which he is optimistic.

"There is no such thing as a golden age. It's just old farts who say everything was better in the past. This is a very exciting time." Bazalgette is a passionate advocate of the digital revolution, and believes it needs funding from the Government. "Now that other organisations are able to make their own content and distribute it online, it doesn't go that public resources should automatically go to the BBC or Channel 4," he says. "That's why I suggest that the trustees of the BBC, who are the representatives of the licence-fee payer and the guardians of the licence fee, could hand it out more widely. This has not gone down particularly well so far but you have to come up with new ideas."

Although a fan of Channel 4 and ITV, he is not too concerned about their futures. "ITV will no longer be a public-service broadcaster, and Channel 4's most important task is to make high-value, high-cost content, and I suspect it may have a narrower remit in future. To those who gnash their teeth about the axing of The South Bank Show, I say: 'Open your eyes. There is a wider world that could do with a little help.' "

Bazalgette recently spoke in favour of targeted online advertising to a broad-based audience at the Convention on Modern Liberty, run by journalist Henry Porter. "They were talking about privacy but you've got to talk about commerce, which is just as important. How are we going to pay for the content of the future? The digital age is in its early stages. We are going to need targeted advertising. But in order to target adverts, they need to know their audience, which means you revealing your viewing habits. If we don't get revenue streams coming in then we won't get original content being made."

Lord Carter is due to publish his report into Digital Britain this month, about which Bazalgette is scathing. "The reason Stephen Carter is doing it is that everyone in Downing Street looked round and thought, 'cripes, we haven't got any revenue from the financial services industry any more, where can we get some from?' But the digital economy is embryonic."

Bazalgette is less happy to discuss his own contribution to the birth of reality TV – a term he abhors – which has arguably revived the 19th-century freak show. This vow of silence lends credence to what one friend says, that Baz is a man of old-fashioned moral values, but that business is business. In this sense, he is not dissimilar to Mark Thompson, head of the BBC and a devout Catholic and family man, who refused to sack Jonathan Ross over the lewd phone calls to Andrew Sachs.

Whatever his legacy, Bazalgette is happy to contribute to television's future from the sidelines. Few can claim to have dictated the zeitgeist quite so single-handedly and profoundly as Baz, even if it was "just telly".