Blockchain technology has started to attract the attention of an array of industries due to the decentralized and immutable nature of it. It has, however, yet to live up to its potential to reshape green investments and sustainable finance. This chapter explores the relevance of blockchain in addressing critical challenges such as greenwashing, lack of transparency, and inefficiencies in financing green projects. Through the lens of real-world scenarios, we break down the potential for blockchain to become a disruptive force in carbon trading, green bonds, and renewable energy markets. The chapter concludes with actionable recommendations for developers, the financial services sector, and policymakers on how to maximize the positive impact of blockchains towards global sustainability goals.