In Lucknow, India, a growing number of homeowners are opening their electricity bills and finding there's nothing to pay. Driven by a rooftop solar boom, more than 100,000 households are generating their own power, cutting costs and embracing renewable energy. Demand has been fueled by government incentives, rising energy bills and growing climate awareness. Uttar Pradesh is the country’s leading solar rooftop state. But beneath the success story, challenges are emerging. Can this solar surge be sustained in the long run? DW's Sadhika Tiwari explores the opportunities, risks and big questions behind one of India’s fastest-growing clean energy trends.