Most of the world’s countries have ratified the Paris Agreement in 2015 and embraced the global fight against climate change. Renewable energy (RE) infrastructure is one of the most relevant mitigation measures to achieve the committed goals, as energy (all forms of energy) accounts for around three quarters of the global greenhouse gas (GHG) emissions ranking it as the largest GHG emission contributor among all sectors. Although taxonomy is not clearly defined in all jurisdictions, climate finance encompasses the financing forms used to fund renewable energy infrastructure and more. Climate finance flows have been estimated at 1.9–2.1 tn USD in 2024, a record (though this represents only a portion of the 7–8 tn USD of capital needed yearly for the energy transition). But climate finance is a complex notion. It refers to public and private funds earmarked to activities that reduce the impact on our environment, financed by official development assistance (ODA) or the collection of carbon taxes among others. Typically, the contributors, besides the private sector (the largest one), active in the financing of renewable energy are funds such as the Clean Technology Fund or Green Climate Fund, as well as global Development Financial Institutions (DFIs) such as the World Bank Group, IFC, AsDB, AfDB, EBRD and EIB. They offer a myriad of financial instruments like guarantees, soft loans, grants and similar incentives or support instruments. And as far as the energy transition in developed countries is concerned, the bottleneck lies in the financing of new clean technology expected to help decarbonize emission-intensive economic activities in industry and transport. For this purpose, strong pledges have been made in Europe, the USA, the UK, Canada, Japan and Australia with the launch of dedicated funds and tax credits. Being introduced to the different options offered by these funds and multilateral banks and to their role in RE finance allows a better understanding and subsequently faster navigation in the “jungle” of climate finance and the maze of multilateral and state-aid structures.