From the International Business Times:
Cities are expected to expand the combined size of Texas, California and Montana in the next 20 years, adding environmental and cultural strains from population growth and shifts away from rural living, experts said Tuesday at a conference in London called "Planet Under Pressure."
By 2030, humanity's total urban footprint will expand by an additional 1.5 million square kilometers (579,000 square miles), according to the conference.
The American model of urban sprawl won't work, raising the question of how to design cities that can sustainably cope with population increases, said Karen Seto, a professor of urban environment at Yale University.
"The North American suburb has gone global, and car-dependent urban developments are more and more the norm," Seto said in a statement. "The way cities have grown since World War II is neither socially [nor] environmentally sustainable."
Reversing the trend toward ever-larger homes will be a big part of designing efficient cities, the researchers at the conference said.
In some countries, urban planners are starting from scratch; the United Arab Emirates and China are both building "zero carbon cities" that aim to run completely on renewable energy.
The UAE's Masdar City began construction in 2008, and aims to house between 45,000 and 50,000 people. Cars will be banned in Masdar City and plans call for power to come from renewable sources such as solar, wind, geothermal and hydrogen energy.
Read the rest at the International Business Times.
Usually I'd pull a quote from The Third here but those who have read the book will get the fact that most of the story takes place in one of the efficient/zero carbon cities described in the article. But you'll have to read the book in order to decide if living in such a city is right for you.