Modeling the strategic contribution of green fintech in green energy financing: Evidence from DCC-GARCH t-copula and causal impact frameworks

The convergence of financial technology (Fintech) and climate change has resulted in a new wave of "green Fintech," a sector dedicated to supporting environmentally sustainable innovation in financial services. Our research shows significant growth of green Fintech from August 2019 to February 2020 and from May 2020 to September 2022, driven by global disruptions such as COVID-19, geopolitical tensions, and crypto-bank failures. Using the DCC-GARCH t-Copula model and causal impact analysis, we optimize a portfolio of green Fintech and energy sector assets from January 1, 2017, to September 27, 2025. Our results reveal strong correlations, underscoring green Fintech's potential to attract capital for clean energy development. Portfolio analysis shows that while dynamic portfolio weights and buy-and-hold strategies provide relatively stable returns, the hedge-ratio strategy delivers the highest cumulative returns, especially when green Fintech is hedged with carbon-emission futures and solar-energy assets. However, during periods of extreme uncertainty, such as the COVID-19 pandemic and the Russia–Ukraine conflict, risk spillovers between energy markets and green Fintech increase significantly, reducing the effectiveness of diversification strategies. This evidence serves as a critical resource for policymakers in designing regulatory and strategic tools to promote resilient, low-risk green financial systems.