Architecture & Design: Never darken my door

Michael Faraday's statue vanishes after dark. Ironic that the inventor of electricity has not even a single lightbulb to stop him disappearing like a genie, but he is just one of many London landmarks that needs new lighting.

Big cities are transformed at night by the magical effects of light. But compared to New York or Paris, London sleeps with the lights off.

The saddest place is the River Thames, according to lighting designer Jonathan Speirs. Cruising down it in a motor-launch after dark, he reveals gaps in the skyline where substantial buildings just disappear at night. Somerset House is wiped out. Embankment Gardens outside the Savoy Hotel become a dense, black thicket. Cleopatra's Needle is missing, Waterloo Bridge turns forlorn and sickly. The church of St Magnus, which stands at the entrance to London Bridge, vanishes - which is why we haven't heard of it - while St Mary's, Gilbert Scott's crenellated wedding-cake of a church in north London has been put back on the map with adventurous illumination.

Other parts of London have blackout areas to match the worst nights of the Blitz. The parks, for a start, and Buckingham Palace most nights. And even when buildings are lit, many simply bleach out and look more like two-dimensional cardboard cutouts. Too much light is as bad as no light. Tower Bridge needs to have the volume turned down. St Paul's, lit from one side to replicate moonlight, looks more like a parody of itself.

"My advice to the new mayor of London is to get a lighting designer, to programme a concerted effort in the same way as Coventry, Liverpool, Edinburgh and Cambridge are orchestrating their city lighting programmes," says Jonathan Speirs. Or Lyon in France, where the Mayor levies a small tax on all its citizens to light the city. Paid for by taxes and funded partly by local business, the annual cost of maintaining the city scheme costs each council tax payer pounds 7 a year. "Fantastic city lighting, but they've gone for quantity, not quality," says Speirs, who believes some buildings should be plunged into darkness.

The Campaign for Dark Skies agrees. "Less light is more revealing," is the provocative message of campaigner Dr John Mason. Dr Mason mourns the loss of our greatest natural heritage, the sky at night. "Who can see the glimmer of the Milky Way in our bright skies ?" Perhaps only one in a million stars is visible. Most of the problem stems from electric light that goes straight up toward the sky, illuminating nothing. Some of this wasted light even bounces off the atmosphere and reflects back on to Earth.

Good lighting is a good deterrent to crime. Since the Middle Ages when, on All Hallows' Eve, the Celts lit bonfires and lanterns to protect themselves and their crops from malevolent spirits, we have believed that light protects us from harm. Now, at night we flood our streets and car parks with light to scare off muggers. But all over the world, in cities and suburbs, a glut of outdoor lighting is obscuring our view. The Dark Skies Association, with branches in 62 foreign countries, is campaigning to do something about it, pushing for legislation against light pollution, hoping to restrict both municipal and private lighting.

They are supported by lighting designers who abhor the ugly, yellow halo that unfocused, wide beam lights bring to buildings such as Unilevers in central London. When Jonathan Speirs was invited by Croydon Council to light their suburban skyline, he had to win over Dark Sky campaigners to prove that the project had widespread community support before they could collect the pounds 2m Lottery money awarded by the Millennium Commission. Thirty-eight buildings on Croydon's skyline will sparkle with kinetic, colourful light; what Speirs describes as a "bit of rock'n'roll". Councillors expect Croydon to take off, with more shoppers, winers and diners, and pedestrians enjoying the newly-illuminated nightlife.

Croydon won Lottery funding, but London First's application for similar funding to light central London's skyline was turned down. All the Lottery allocation went instead to the Dome, where the spotlight will fall at the turn of the millennium.

Stepping into London's Millennium Dome at night will be like having a heavenly night-sky overhead. Purple-blue lights beamed from the floor will play upon the vast, spherical space to make it more intimate. Because the roof is translucent (to capture as much daylight as possible), that blue light at night will soften its profile so that the Dome doesn't light up like a flying saucer. Inside, red and white light will play upon the lap circuit that runs around the central arena. By day, the light inside the Dome is white and cool.

"Visitors will definitely have to come twice to experience those very different climates created by day and night," says Speirs, who is responsible for the lighting along with his partner, Mark Major.

To prove how lighting changes the character of a building, lighting manufacturers Philips built a model village outside Lyon, around a village square, scaled two-thirds down from life-size. A computerised light programme plays upon the model of a neo-classical town hall. Simply by changing the light, the way the building is perceived alters. A welcoming glow at the entrance lures theatregoers inside, as the rest of the building is mysteriously wrapped in wraiths of silvery light. Pinpointed with light, like Harrods, it turns into a casino. As the Courts of Justice, it takes on a steely, cold light that is authoritative and sobering. For the bank, the columns are illuminated as the props that stabilise the building. At night, its identity is established purely through light.

`Bright Lights, Big City' will be shown on ITV on 16 Feb at 7.30pm