Deep reductions in CO2 emissions are needed in energy production and use, which constitute two-thirds of the emissions responsible for climate change. Achieving such reductions requires concerted government policy in all countries, with attention to interrelated challenges like inclusive and sustainable growth. Introductory Chapter 1 of this dissertation on the economics of decarbonization proposes that the four stand-alone analytical chapters can be understood together along the cross-disciplinary technology innovation process: (1) the evolution public energy research, development, and demonstration (ERD&D) across technologies and countries (Chapter 2); (2) the effects of policies aimed at creating markets for low carbon energy on decarbonization (Chapter 3); and, (3) the changes in trade of materials used in energy technologies (energy technology materials, ETMs) for technologies in early adoption and diffusion (Chapters 4 – 5). Existing statistical and econometric studies on these topics tend to focus on high-income (World Bank classification) OECD countries, which we define as “developed.” Instead, this dissertation takes a broad geographical view by creating new datasets, using existing ones in new ways, and proposing changes to established methodologies to better understand the developments and challenges of the energy transition in a wider set of countries. Chapter 2 ascertains that the evolution of global ERD&D is several times too small compared to existing estimates of what is needed to meet climate goals, even when accounting for previously unavailable data on China and India. Volatility of funding by country and technology groups (fossil fuels, nuclear, and clean plus (CP)) points towards innovation systems patterns over the United States/United Kingdom, continental Europe, and Asia. With some caveats, the years after two windows of opportunity for changes in funding patterns were not associated with significant changes in funding allocation towards CP. Chapter 3 finds that the policies with the most immediate positive impact on energy decarbonization in developing countries from 1980-2018 dealt with counterparty risk, referring to the bankability of private participation. The impacts on decarbonization of other policy instrument categories (e.g. legal frameworks for renewable energy) are low but tend to increase with time, and we discuss possible reasons why. Chapter 4 identifies 30 traded products related to ETMs. It finds that over the two decades between 1998-2018, trade trends (such as growth, volatility, importer concentration, and exporter concentration) in two groups, clean and refined products, display relatively beneficial changes for exporters than traditional and unrefined products do. In accordance with existing literature, however, developing countries are underrepresented as exporters of clean and refined products. The results make a case for enhancing clean and refined ETM trade and capabilities in developing countries. Chapter 5 proposes a methodological modification to the estimation of existing structural trade demand price elasticities (defined as a change in quantity traded due to change in price). The modification allows for a comparison of the trade demand price elasticities for exporter-ETM pairs in almost 30 traded products and 20 major developing and developed country exporters over the two decades between 1998-2018. We find, amongst other things, a convergence between developing and developed countries over the past two decades and discuss possible reasons for this pattern. Chapter 6 considers the implications of the results and reflects on directions for future research.