Policy coherence for sustainable development (PCSD) and environmental security are crucial for achieving sustainable development, yet their intersections remain largely unexplored. In this article, we combine these two approaches to examine renewable energy policies of the European Union (EU). The EU is a key actor championing sustainable development, often considered to be a ground breaker particularly in environmental policies. At the same time, the EU aims to be a significant global security actor, and it has also recognised the role of environmental change as a factor for security. In this article, we explore whether the EU coherently integrates the sustainable development dimensions (society, environment, economy) in its renewable energy policies through inductive and deductive content analysis of key policy documents. Our analysis shows that the EU's renewable energy policies are not fully coherent with all dimensions of sustainability, particularly with respects to societal considerations and impacts on third countries.