1. Energy: what for?

Energy is essential to the economic development of mankind and the improvement of living standards. It is mainly consumed in thermal form (heat or cold), for transport or to generate electricity. Food is also a form of energy, but is not included in energy balances. It was the main source of energy for primitive man, whose diet was much poorer than today's in developed countries. Today, the energy content of food represents only 5-6% of the energy consumed worldwide. But it remains essential.