Energy in Economic Production
Energy is indispensable for economic development and growth. Productive demand caused by the increase in economic production will increase faster than that of economic growth in the earlier stage, but, eventually slow down passing the certain point. This phenomenon takes place due to a change in industrial structure, technological advance, and substitution of labor by capital. As an economy grows, the structure of industry transforms from a labor-intensive primary industry to a secondary industry in which relatively more capital- and energy-intensive heavy and petrochemical industry will be dominant. Later, the higher level of economic growth calls for a tertiary industry which requires less energy consumption.
[Energy Supply and Demand in the Stages of Economic Development]