Reuters: At the age of 32 and worth US$4.4 billion, solar wafer maker Peng Xiaofeng is proof, as countries argue in Bali over who should pay to fight climate change, that there is money in protecting the environment. Peng is chief executive of China’s LDK Solar, a company he founded barely two years ago, which has cashed in on government subsidies and soaring public demand to go green. He was already well-off before founding LDK, but had found the family business, in personal …