ARPA-E is the very best example of energy innovation policy as it invest in truly breakthrough high-risk projects that if any one succeeds would have a transformative effect on the global energy system. And the ARPA-E Energy Innovation Summit is one of the biggest collections of thinkers, business leaders, and policymakers all working to support and innovate cheap clean energy technologies. A pervasive theme of the Summit is a simple question: How can we accelerate and spur clean energy innovation? Through speakers and panels, the conference addressed all aspects of this question from public policy changes to new business models. Senior Policy Analyst Matthew Stepp and Research Analyst Clifton Yin provide coverage and commentary of the event by teasing out main themes and policy ideas discussed at the Summit.