The present thesis addresses the policy and technological aspects of national (and sub-national) greenhouse gases (GHG) abatement strategies. Two of the three chapters of this thesis explore the former, respectively investigating (i) domestic political economy constraints and (ii) processes of policy diffusion across jurisdictions. One chapter focuses on the latter, advancing methodologies for the identification of firm-level innovation in (GHG- reducing) electricity supply technologies.

A key empirical contribution of this thesis, presented in the first chapter, is the construction and calculation of an average (emissions-weighted) price of carbon for the jurisdictions under study, which shows, among other insights, that the world average price remains extremely low, at about 1.5USD/tCO2e in 2018. In addition, the analysis in this chapter suggests that (i) political economy factors primarily affected policy implementation and (ii) policy stringency is a highly persistent process.

Our next chapter investigates policy diffusion processes and proposes that these are related to an alteration of the net payoffs of domestic climate policy and an update on the information about the benefits (or costs) of policy adoption derived from the adoption of a similar policy or the deployment of abatement technology in foreign juris- dictions. The evidence suggests that technology demonstration and learning from past policy experience positively affect (domestic) policy developments.

The last chapter focuses on the identification of (GHG-abating) electricity supply technologies using a machine learning search strategy based on patents’ title and abstract. This approach highlighted the role of “lateral" innovation in the development of some electricity generation technologies. In addition, by linking the identified patent set to legal entities, we uncover the role of firms’ technological entry and exit in technology transition and shed light on the business structure of technologically active entities.

The present work allowed me to address fundamental questions pertaining to the design of climate change mitigation strategies. First, our results stress the importance of the sequence of introduction of the climate policies, suggesting that policies weakening incumbents’ political and economic influence might foster subsequent implementation of more stringent policies. Second, given the weakness of most existing carbon pricing schemes, a rationale for the development of climate mitigation strategies with multiple GHG abatement tools continues to exist. Third, mechanisms of policy diffusion at play could prove highly valuable when seeking to introduce carbonpricing mechanisms in new jurisdictions. Finally, we point at the need to target public support to sustain the stream of GHG-abating electricity supply technologies primarily at new (technological) entrants.