In this subtropical country of more than 165 million people, Pakistanis are in the habit of shopping late, and many shops used to stay open until 10 p.m., or even past midnight.

Despite the ongoing Taliban insurgency here, the economy has been growing fast, at more than 5 percent a year for most of the past decade.

Power production hasn’t kept up with booming demand. Many blame short-sighted government planning and failure by both government-managed and private power providers to build new generation stations. Others point out that conflicts between Pakistan's provinces have hampered the building of more hydroelectric dams. (Water shortage also is a chronic problem.)

(See “Nuclear Reactors, Dams at Risk Due to Global Warming.”)

Regardless of the reasons