WHEN the Old Etonian leader of the Conservative Party chooses to adorn his Kensington roof with a wind turbine, you know that saving the planet is no longer a minority hippy pursuit. Now Mr Cameron’s millionaire neighbours are beginning to realise that a luxury home kitted out with the latest in eco-gadgetry is not only a chic accessory but may be a sound investment.

An early adopter of the “sustainable luxury” trend is Andrew Murray, of Morpheus Developments, whose website reassures the Barbara Amiels of this world that “every conceivable extravagance” can be accommodated in a Morpheus property, “no matter how fastidious the request . . . be it a waterproofed X-box for a bathroom . . . or cabinetry designed solely for a client’s entire handbag collection”. Forget The Good Life, this is sustainable living reborn as good old-fashioned status symbol.

Murray’s latest project is a muddy hole on the former site of the Webber Douglas drama school on Clareville Street in South Kensington. By December, the hole will be filled with three four-bedroom townhouses, priced from £4.5 million, each consisting of 3,669 sq ft of space spread over five floors and heated by 18 geothermic boreholes 100m deep.

Clareville Street, running north from the Old Brompton Road and then west into Hereford Square, is quiet, pretty and neat as a pin, with rows of mews-style houses and a Catholic primary school, Our Lady of Victories. The area is popular with French expats, whose children attend the Charles de Gaulle Lycée on Cromwell Road, a five-minute walk away.

The houses will go on sale off-plan in May and complete in December, two months later than planned owing to a fleeting incompatibility between the boreholes and Clareville Street’s rock strata. “This is the first time we’ve used them,” says Murray, “so they were an unknown quantity.” The boreholes, which Murray estimates will reduce energy bills by up to 70 per cent, will provide all the heating and hot water, and will even heat the drive — useful during those notorious Arctic winters in SW7. Also thrown in are solar panels, sustainable materials, rainwater harvesting, waste compactors, lambs-wool insulation and low-energy lighting.

Each layout is identical — a basement with home cinema, fully equipped gym with en suite steamroom and shower, staff bedroom and cellar with cigar humidor. The lower ground floor houses a garage, kitchen and terrace, while a living/dining area and second terrace are on the upper ground floor. The first floor is given over to the master bedroom suite with “his” and “hers” bathrooms, dressing and sitting room. Two further bedrooms and bathrooms reside on the top floor.

Techno-wizardry abounds. “The whole house is wired for sound,” says Murray, “using Crestron touch panels, which also control the security system and heating. These can also be managed remotely with a mobile phone or lap-top.” Finally, for those who cannot bear to be separated from technology even while performing the most mundane of daily functions, there will be waterproof televisions in the bathrooms and computer-controlled curtains. Murray estimates that the green gadgets will cost £50,000 per house, a sum that he will not pass on to buyers, who may as yet remain unconvinced of the value, moral and financial, of an energy-efficient home. “These houses would sell for the same price without the eco-features,” he says, “but we hope it will make them more attractive, so they will sell more quickly. Time will tell how popular it will prove.” Taking this gamble also enables Morpheus to stay one step ahead of building regulations, which are evolving rapidly as government gets greener.

Eco-kit is particularly popular with Europeans, Murray says, and he expects his eventual buyers to tick one of the following boxes: “French, City boys, hedge-funders with one or two children”. Come June, when Energy Performance Certificates (EPCs) become compulsory, forcing sellers to rate the eco-friendliness of their homes, Brits may begin to value energy efficiency too. Developers expect EPCs will eventually affect house prices, a trend that is likely to come from the top down, Murray says. After all, he points out, Chelsea tractors may be driven by the wealthy, but this sector is also the one buying hybrid cars. “I don’t mean to sound snobbish,” he says, “but if you educate the top end, the rest will follow.” www.morpheusonline.com, 020-7610 7170

Times recommends

• Fall in house sales hits builders, estate agents and mortgage brokers
• Why the property credit crunch favours cash buyers
• The blood-curdling history of Quarrelwood House