The rich are different from you and me, F Scott Fitzgerald observed, earning Ernest Hemingway’s rejoinder, “Yes, they have more money.” In Britain the distinction has been accentuated by a new breed of super-rich known as the “hedge fund kings” who are giving their millions away. Their credo “greed is good” now carries an appendage that “giving is better”.

Perhaps it was inevitable. Once you have bought a £200,000 Bentley, colourcoordinated your Gulfstream jet with the yacht and spent £300,000 on a diamond ring for your wife’s birthday, only one thing can make you feel as good as sampling a £1,200 bottle of champagne — doing something for your fellow man.

Such is the explosion of what has been dubbed “venture philanthropy” and “philanthrocapitalism” among the nouveaux riches that Britain’s first philanthropy school opened its doors recently to multi-millionaires intent on learning how best to give to charity. Such knowledge does not come cheap: a week’s semi-residential instruction costs £6,000.

The courses are run in London by the recently created Institute for Philanthropy, an offshoot of the fabulously wealthy Rockefeller Foundation and administered by Salvatore LaSpada, the son of impoverished Italian immigrants. “What is in it for them is the feelgood factor and the sense of satisfaction from spending money that is far greater than the satisfaction they might feel from owning yet another home or yacht,” he says.

The City’s movers and shakers are minnows compared with the 75-year-old investment strategist Warren Buffet, the second richest man in America, who last week made the greatest charitable gift in history by pledging $31 billion of his $44 billion fortune to the Bill and Melinda Gates Foundation in instalments. He, and they, are following in the footsteps of the Scottish-born steel magnate Andrew Carnegie, who gave $350m (equivalent to around $8 billion today) to build libraries and other projects throughout America at the turn of the 20th century.

Yet Britain’s new philanthropists share with Buffet and Gates a mixture of impatience and business acumen that is shaking up the charity world. Reluctant to sign away their money to traditional NGOs, they are adopting a hard-nosed approach that insists on looking at the bottom line. They want to make a difference, but balk at feeding the maws of self-perpetuating bureaucracies that squander money on administration and promotional campaigns. If charities don’t cut the mustard, they are prepared to go it alone.

A typical skill-building exercise at the Institute of Philanthropy features an imaginary entrepreneur who sells his business and moves to a fictional Pacific island to invest his millions in social projects. “They are involved in all sorts of things, from juvenile justice to women’s rights in the developing world, renewable energy, public health projects, you name it,” LaSpada says.

Besides altruism, the trend is spurred by several motives ranging from cheating the taxman to the fear that the children will blow an inheritance on a life of extravagance. A sense of mortality also plays a big part. Both the American multi-billionaires had planned to give away their fortunes at their deaths until the death of Gates’s mother and Buffet’s wife provided their Scrooge moments. “It’s something you can’t buy,” Buffet discovered. “The way to be loved is to be lovable. You always get back more than you give.”

The decision by the old “Sage of Omaha” to park his money in the tightly focused organisation run by the 50-year-old Gates reflects a determination among Britain’s hedge fund kings to get the best for their money. The trend is apparent to New Philanthropy Capital (NPC), which advises donors and charities on how to be more effective.

“What we’re seeing is potential and actual donors becoming more and more concerned with the effectiveness of the charities they support, how the money is used and what difference the charities actually make on the lives of the people they work with,” says Nigel Harris, NPC’s chief executive.

A charity beloved of the hedge fund kings is Ark (Absolute Return for Kids), which pays close attention to how the money is spent, primarily on tackling HIV-Aids in South Africa, helping orphans in eastern Europe and on academy schools in Britain. It was founded by Arpad “Arki” Busson, best known as the former boyfriend of the supermodel Elle Macpherson, with whom he has two children.

Busson, 44, began his career selling toothpicks in his native Switzerland and is today one of the most powerful and flamboyant figures in the City, running his EIM hedge fund operation from a penthouse office in Mayfair. Thanks in part to his contacts, Ark recently raised £17.5m at a lavish ball at Marlborough House where 1,000 guests, including the environmentalist Zac Goldsmith, Sir Stelios Haji-Ioannou of easyJet and the former racing driver Eddie Jordan, were serenaded by Sir Elton John.

A game of tennis with John in the south of France was auctioned for £70,000, while a guitar lesson with Chris Martin, the lead singer of Coldplay — followed by dinner with his actress wife Gwyneth Paltrow — made £140,000. Bill Clinton sent a personal letter of endorsement to every guest and Archbishop Desmond Tutu videotaped a message of thanks. Ark’s supporters had pledged £3 for ever £1 raised at the auction.