Nowadays,when a great progress of civilization is taking place, energy is the key to sustainable development.It has always been indispensable to most human activities such as domestic life, agriculture, industry and transport.Now it is a precious good but today's energy system is dominated by the powerful and centralized supply of fossil fuels.80% of them are consumed in industrialized countries and they account for 80% of carbon emissions-the main cause of the greenhouse effect.World population is expected to double by 2050 and the result will be that energy consumption will tripl
One can imagine the level of environmental pollution resulting from several decades of demographic growth. The benefits are beyond doubts as they contribute to a big cut in the emission of CO2. They create no pollution and can be opetated almost anywhereand require little maintenance. The amount of needed energy will probably increase thanks to the development of technology and new equipment. This technology works economically and is not connected to national power plants. Biomass is another major alternative energy source. The renewable energies will surely be needed when a big increase in the demand of energy takes place. provide industrial growth and improve standard of living. But this way of gaining energy brings a lot of problems. water, modern biomass(wood harvested in such waysas to avoid alterinf the forests). The development of these new sources offers a better access to energy service. First,the consumption of energyshould be saved and secondly,more flexible fuels(renewable energies)should be used.