La financiación sostenible en la Unión Europeaun análisis de los bonos sociales y verdes

Abstract

In the last quarter of the 20th century, the growth model of developed countries began to be questioned as unsustainable. This concern has intensified in recent years, with events such as the 2015 Paris Climate Summit and the adoption of the 2030 Agenda with its seventeen Sustainable Development Goals (SDGs) that same year. These developments have increased interest in sustainable finance and Socially Responsible Investment (SRI), capturing the attention of governments, corporations, investors, and the scientific community. The European Union (EU) has played a key role in the field of sustainable finance and SRI. Through its commitment to the Paris Agreement and the implementation of the European Green Deal, the EU has taken measures aimed at making Europe the first carbon-neutral continent by 2050. Furthermore, its regulatory work on sustainable financing instruments, particularly green bonds, is noteworthy. The EU has established a Taxonomy for sustainable activities and the EU Green Bond Standard, which has significantly boosted the European market for green bonds and other debt instruments aimed at financing environmental, social, and governance (ESG) projects. Simultaneously, the COVID-19 pandemic and its negative social and economic effects heightened the need to implement aid plans to address the crisis. The EU responded with programs such as Next Generation EU and Regulation (EU) 2020/672, aiming to mobilize hundreds of billions of euros to reactivate the economy, protect employment, and promote sustainable, digital, and resilient growth. These programs facilitated the issuance of green and social bonds by the EU for their financing. The growing importance and interest in socially responsible investments for the transition to an environmentally sustainable and socially inclusive economic model motivated this doctoral thesis, structured as a compendium of publications, to explore aspects related to sustainable financing through instruments such as green and social bonds that contribute to achieving this model. The first scientific article presents a bibliometric analysis of sustainable finance, SRI, and green bonds to contextualize the research subject, underscoring the EU's role as a knowledgegenerating area and as a regulatory and institutional leader. Additionally, this analysis found that sustainable finance is strongly associated with environmental factors. While issues related to the performance of green bonds, such as the green premium, are well-studied in the scientific literature, this is not the case for social bonds. The second article provides a descriptive study of the European green bond market between 2007 and 2023 to assess its global significance given the substantial financing needs to meet the EU's environmental goals at the institutional level. This study confirmed the importance of the European bond market worldwide and of the EU, not only as a promoter of social and environmental investments but also as a debt issuer for such financing. Finally, the third article presents an empirical study on green and social bonds issued by the EU to fund the Next Generation EU and Regulation (EU) 2020/672 programs, aimed at determining the existence of a green or social premium. To this end, these bonds were compared to conventional bonds from the same issuer in the secondary market, using multiple linear regression analysis. The findings highlight that green and social bonds with higher levels of liquidity also exhibit higher yields, while greater volatility implies that secondary market investors require higher rates. Additionally, social bonds show wider yield spreads compared to green bonds, indicating that the social premium is larger than the green premium, suggesting that investors may show a preference for bonds issued to finance social projects.