Thesis advisor: Michael Grubb / With the implementation of the Inflation Reduction Act (IRA) raising concern of clean energy capital flight from the European Union, investigating the effects of US clean energy expansion policy on international investment shifts is a pertinent issue. This paper uses event studies to analyze debt capital market dynamics through green bond spreads, using conventional corporate and government bonds as separate benchmarks. It finds that the simultaneous extension of ITC and PTC policies in 2015, 2020, and 2021 did not consistently produce a significant effect on green bond markets in the US and EU. This implies that the implementation of clean energy policy in the US has an insignificant impact on green debt capital markets in the US and EU, although impacts on other investment channels cannot be ruled out. A further analysis on green investment sensitivity to interest rates indicated a significant negative sensitivity for green US firms only, although this was inconsistent across measures. / Thesis (BA) — Boston College, 2024. / Submitted to: Boston College. Morrissey School of Arts and Sciences. / Discipline: Economics. / Discipline: Departmental Honors.