Figure 2.5 Projected World Energy Shortfall 2.1.4 Conclusion The level of growth in future energy needs as shown in the different models will cause severe problems in terms of finances, resources and pollution. The energy available is inadequate for the projected needs, even in the low growth scenarios. It is difficult to foresee terrestrial renewable energy sources that can provide enough energy without causing serious environmental problems. One alternative technology could be space based solar power which is an inexhaustible source of clean and safe energy. Solar space power could probably eliminate all restrictions and limits of future growth. In our opinion the future energy usage model by Lomer seems to be a realistic projection. It gives a high and low case for future energy consumption until 2100. The assumptions for this model are not restrictive in terms of economic growth with respect to the developing and developed countries. This model comes to the conclusion that there will be a 2.5 to 5 fold increase of the current energy consumption by 2100. The model of Dessus and Pharabod is in fact very optimistic. Compared to the different scenarios described in the energy demand model by Lomer, the projections for future energy demand by 2100 in the Dessus/Pharabod model are even below the estimated range of 17-50 TWy/year predicted in the previous model. [Lomer 91, Deschamps, 1992] Hence this model does not seem to be very reasonable to us. The carbon cycle model of Edmonds and Reilly shows also a high future energy demand in 2100 and clearly indicates the need for other energy sources than fossil fuel or atomic energy. Power from space could be one of the options for safe and clean energy. From the environmental standpoint of view space solar power seems to be a very reasonable energy form for covering the increasing future energy needs of the world. 2.2 Terrestrial Energy Supply The previous section addressed the question of how much energy may be needed in the future and what it will be used for. The actual amount of energy actually provided will depend on a variety of factors including production cost, available supply, and other market related issues. Section 3.2.4 will address the relationship between supply and demand and will discuss market characteristics that influence pricing and energy availability. This section will be concerned with the question of how energy needs will be provided. The following subsections include a description of the various sources of energy and their characteristics, the conversion processes for the major uses of energy, and the cost (present and future projections) of providing energy from each source. The major goals of this section are to provide a realistic basis for evaluation of future energy sources and to establish a cost target for the space solar power program to determine the circumstances under which it will be cost effective.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==