Skyscraper Lights Don't Have to be Dangerous or Wasteful

"New York structural engineer David Scott, the chairman of the Chicago-based Council on Tall Buildings and Urban Habitat, put that point in a broader context when I reached him by phone on Monday.

'If you just turned everything off, you would lose a lot of the [urban] vibrancy,' he said. 'If you weigh up the efficiencies you get by people working and living in a city, particularly a city that's served by public transport, you can afford to be generous with some of the lighting.' Many skyscrapers around the world, particularly in Hong Kong, are now lit with LEDs that use far less energy than conventional spotlights, he added.

Call it the 'bright lights, big city' theory of urban planning: By doing a modest amount of decorative lighting, either atop of a building or in places that accent key architectural features, you prevent the city from feeling like a ghost town. That encourages more people live in dense urban areas. And density saves energy. You spend a little energy to save a lot of energy.

A green city is not a blacked-out city."