Energy supply security is of paramount importance to all countries, however, not all countries present the same capacity to respond to energy security threats. Financial wealth is one of the means that can support access to energy resources and as such countries that have been hit the hardest by the 2008 financial crisis present energy supply vulnerabilities. We focus on Ireland, Portugal, Spain, Italy and Greece and find that they have continuously improved their energy supply diversity. At the same time, we argue that during, and as a result of the financial crisis our focus countries reduced their exposure to expensive imported resources predominantly in the transport sector and increased the role of renewables. Overall, we find improved supply security which could be strengthened further if financial resources were directed towards innovation for renewable energy sources. © 2017 The Authors.