This article assesses and explains the level of climate policy integration (CPI) in the EU's energy sector, and challenges the widespread assumption that a high level of CPI has been achieved in this sector. We introduce a conceptualisation of CPI and outline an analytical framework to explain levels of CPI, drawing on Environmental Policy Integration (EPI) literature and on theories of European integration. We thus add conceptual value by bringing strands of EPI literature together and situating them in broader theories of European integration. We analyse CPI in two cases of energy policy: the EU's renewable energy (RE) policy and EU policies on gas pipelines. We argue that even in the relatively climate-friendly RE case, the level of CPI remains insufficient to reach long-term climate policy objectives. CPI has been virtually absent in the EU's gas import pipeline policy. The lack of CPI may remain hidden without taking a long-term perspective. The explanatory framework helps us in understanding the insufficient levels of CPI and the differences between the cases. We argue that serious consideration of long-term climate objectives in the policy process is fundamental for the occurrence of CPI.
