Meeting the European Union's natural gas demand will require increasing volumes of imports in the foreseeable future. Recognizing the need to ensure uninterrupted and secure supplies of natural gas imports at all times, the European Union (EU) has actively sought to diversify its sources of supply, including obtaining natural gas from Azerbaijan through the Southern Gas Corridor (SGC). In pursuit of this objective, the EU has provided financial support for parts of the Southern Gas Corridor. In this paper, a combination of cost economics and Rational Choice Institutionalism (RCI) framework has been used to explain the policy choice made by the EU to support the SGC. We observe, that the choice of using the SGC as a supply source has been despite the relatively higher cost of delivery of Azeri natural gas into the EU. The motivation for the EU here is characterized by the strategic importance and part of its efforts to diversify sources of supply in the RCI framework. In this context, the EU is delivering energy security services to its member states who in turn have muted their sovereign rights in exchange for a diversity in the source of supply. This is possibly the only study that measures up the economic cost against choices made under RCI in natural gas security literature.

要满足欧盟的天然气需求，在可预见的未来将需要增加进口量。认识到需要始终确保不间断和稳定的天然气进口供应，欧盟（EU）积极寻求使其供应来源多样化，包括通过南部天然气走廊（SGC）从阿塞拜疆获取天然气。为了实现这一目标，欧盟为南部天然气走廊的部分地区提供了财政支持。在本文中，成本经济学和理性选择制度主义（RCI）框架的结合已被用来解释欧盟为支持SGC而做出的政策选择。我们观察到，尽管将阿塞拜疆天然气输送到欧盟的成本相对较高，但仍选择使用SGC作为供应源。在此，欧盟的动机在于其战略重要性以及其在RCI框架中实现供应来源多样化的部分努力。在这种情况下，欧盟正在为其成员国提供能源安全服务，而这些成员国反过来又放弃了主权主权，以换取供应来源的多样性。这可能是针对天然气安全文献中根据RCI做出的选择衡量经济成本的唯一研究。