This lecture illustrates a few key concepts for understanding the relevance for our economies of the supply of fossil fuels, in particular oil and natural gas. It looks at the somewhat blurry distinction between reserves and resources and discusses some reasons for the uncertainty that typically affects these metrics. After briefly touching upon the peak oil issue, the presentation discusses the increasing relevance of unconventional oil and natural gas resources.
The second part of the presentation focuses on the concept of security of supply and illustrates a few indicators suggested in the literature to measure the main dimensions of energy security, namely dependence and vulnerability. A brief mention of the broader issues that concur to determine the security of supply of a given country, and a reminder of the main take home messages for this topic, conclude the lecture.