Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
The import risks confronting oil consumers are influenced by transport conditions, oil prices, geopolitics, etc. This paper constructs an evaluation framework for oil import security from a perspective of supply chain process, and builds a two-phase DEA-like model to evaluate oil import security. China is taken as an example to measure its oil import security during 1993–2011 and to identify the main risk factors in different periods. Results indicate that China's oil import risks have kept rising since 1993 and face multiple potential threats from each stage of oil import supply chain, among which the threat from external dependence has become the biggest challenge. Under different economic situations and changing energy environment, the risk factors affecting China's oil import security switched among different stages of the supply chain, showing a phase-transitioning characteristic from import over-dependence to increasing external supply pressure. The threat of external supply has become a new risk since the pressure of decreasing availability of external resource rose.