Motivation

The global consumption of primary energy has been marked by a strong increase in the past 40 years. Figure 1.1 presents the development of primary energy consumption, broken down into groupings, namely industrial countries of the OECD; former Soviet Union; and emerging economies (i.e. developing countries). In 1965, the worldwide consumption of primary energy amounted to only 3,860 MTOE (million tonnes of oil equivalent); by 2005, it had increased to 10,224 MTOE. This corresponds to an increase of 172% or an annual rate of increase of 2.5% (BP 2008). In industrial countries, the increase was around 107% for 40 years, corresponding to an annual rate of increase of almost 2%. In the emerging economies, which started from a lower absolute level, the increase was 640%, which corresponds to an annual rate of increase of more than 5%.