Harvesting renewable energy, solar power, waste management - these concepts have been much explored across the world in the last decade. But has India made its presence felt in this field? Maybe not in the last few years, but now things are changing around. Upcoming start-ups are giving the renewable energy sector a new lease of life. Just how are these start-ups setting new benchmarks in this field, Ankita Sinha and Lakshmi Sivadas find out.