This guidebook shows how India plans to meet its ambitious rooftop solar energy targets and why identifying new business models, engaging utilities better, and developing new market mechanisms will speed up its adoption. It explains how factors such as access to finance, policy uncertainty, and a lack of credible developers are slowing the roll out, and how demand aggregation can help utilities lower costs, reduce risk, and expand market opportunities. It offers a step-by-step guide for utilities to design demand aggregation programs and recommends that they introduce targets, build capacity, and run marketing campaigns to grow rooftop solar power generation and help reduce India's emissions.