Is energy security compatible with sustainability? A structural system analysis

This study examines whether energy security is structurally compatible with environmental sustainability under contemporary energy transition pathways. Using an unbalanced panel of 112 countries over 2000–2023, we estimate a three-stage least-squares system linking energy security, greenhouse gas emissions, and sustainability performance. Compatibility is defined as a positive and statistically distinguishable total effect of energy security on sustainability operating through emissions, conditional on the renewable energy share. In the full sample, stronger energy security is associated with higher emissions, while emissions reduce sustainability performance, resulting in a negative total effect at the mean renewable share. The relationship nevertheless differs across country groups. Among OECD countries, renewable penetration attenuates the emissions response to improved energy security, and the resulting total effect is smaller and only marginally distinguishable from zero, indicating movement toward, but not the achievement of, compatibility. In the EU-28, renewable penetration is directly associated with stronger energy security and lower emissions, although it does not significantly moderate the security–emissions relationship. By contrast, renewable penetration strengthens rather than weakens the emissions response in the full and non-OECD samples. These findings show that renewable deployment can facilitate the alignment of energy security and environmental objectives through different channels, but a higher renewable share alone is insufficient to secure compatibility. Its contribution depends on the composition of renewable deployment and its integration into the wider energy system.