Since the COP21 climate conference in Paris in 2015, India has wanted to emerge as a major player in the fight against climate change and is betting on a transition to clean energy. The country is indeed seriously threatened by climate disruption, with melting glaciers in the Himalayas, droughts, torrential monsoon rains and severe air pollution. But Prime Minister Narendra Modi's government faces a daunting challenge: how to reconcile economic growth with clean energy initiatives. Our reporters went to investigate.