This report clarifies the nature of oil reserve estimates, the methods by which they are produced, the manner in which uncertainty is estimated and expressed, and the difficulties of aggregation. It summarises and compares number of commonly used classification schemes and investigates why reserve estimates change over time. It highlights both the limitations of current estimates and the extent to which they may be misinterpreted. It concludes that current reporting practices are only poorly suited for the purpose of forecasting future global oil supply.
This report forms part of the TPA’s assessment of evidence for near-term physical constraints on global oil supply. The assessment addresses the following question: 'What evidence is there to support the proposition that the global supply of ‘conventional oil’ will be constrained by physical depletion before 2030?'