2. Energy: stability in the 20th century

From the 1950s until around 2000, energy production and consumption increased considerably, but the main characteristics of the sector changed little:

• predominance of oil as the main energy source ;

• natural gas development ;

• stagnation of coal, which pollutes and is less convenient to use than the other two major fossil fuels;

• significant but limited development of nuclear and hydro power.

Fossil fuels account for 80% of energy consumption – and even 90% if we exclude wood, which is still important in sub-Saharan Africa and some poor countries in Asia and Latin America