In his academic work Llewelyn is interested in how public policies affect, and are affected by, energy markets. He is currently investigating how and why energy policies are changing in response to the problem of climate change, with a particular focus on the Asia-Pacific region. A second project examines how exposure to extreme weather events affects beliefs in climate change. Llewelyn also has an interest in fossil fuels. In 2014 his book Globalizing Oil was published through the Business and Public Policy series with Cambridge University Press (reviewed here by Paul Stevens in The Energy Journal). His research is published or forthcoming in Annual Review of Political Science, Business and Politics, Climatic Change, Energy Policy, Environmental Science & Policy, Global Environmental Change, International Studies Quarterly, and other academic journals, as well as in numerous policy outlets.

Llewelyn Hughes is Associate Dean for Research at the College of Asia & the Pacific, Australian National University (ANU), and an Associate Professor at the Crawford School of Public Policy. He also sits on the Executive Committee of the ANU’s Energy Change Institute.

Llewelyn is responsible for the provision of high quality leadership in research within the ANU's College of Asia & the Pacific. His portfolio includes responsibility for promoting a culture of research excellence and research productivity in the College, and leading the management and direction of the College’s research performance, profile and quality.