Reuters: Seven years ago, the Chinese city of Baoding launched an ambitious "low-carbon" plan using renewables like solar power to light its streets and heat residential buildings, putting it at the forefront of the country's battle to cut pollution.
In 2013, Baoding was still the third most polluted city in the country, with levels of harmful particles in the air more than 40 percent above those in the nearby capital Beijing.
Baoding's failure to clean up its act underlines the scale of the challenge...