Energies, to anticipate the shortages

The problem of energy is important and difficult to solve. No mode of energy production is free from problem, either at the pollution or waste level, or contribution to greenhouse effect, or cost level. it can be added questions of geo policy, and acceptability by public. The most important constraints for future are the available quantities and the global warming. The only way to progress is to add the contribution of renewable energy sources. Solar energy must have its place in houses heating, biomass has to be used either to complete heating or to contribute to transports. But all these things will not be sufficient. Fossil energies will be used, petroleum and gas as long as the supply is possible and coal, more abundant but with carbon dioxide sequestration to limit greenhouse effect. Nuclear energy will be necessary to supply electric power and a development of hydrogen option, these two vectors able to take a part in transport. This being so, it is necessary to apply a policy of energy conservation and efficiency, each of us, as citizen has to give its contribution by inciting our governments to manage this question as a priority but also by avoiding wastefulness, by privileging the public transports, by switching off the electric installations or lights. One by one, each energy source is studied in detail through its reserves, its technologies, its contribution to greenhouse effect. (N.C.)