In this study, the energy cost of launch vehicle manufacture is estimated by referring to data for the aluminum and iron & steel industries [8]. According to the data for aluminum in 1984, the energy for production of the raw material is about 40 MJ/kg, and the energy for manufacturing general machinery or electrical machinery from raw materials is about 20 MJ/kg from the data for the iron and steel industry. Therefore, the specific energy per mass for launch vehicles is taken as approximately 60 MJ/kg, and the specific energy per mass of payload (SPS) in GEO is taken as 1200 MJ/kg since the ratio of vehicle dry mass and SPS mass in GEO is about 20. In this study, it is assumed that the launch vehicle is disposable and the energy for vehicle manufacture is 1200 MJ/kg for simplicity. However, each launch vehicle could be reusable, and then this energy would be significantly lower than that value, since it could be divided by the number of flights. World Dynamics Simulation Model With SPS The system diagram of the model in this study is shown in Fig. 2. The Earth section of the model is based on Forrester’s WORLD-2 model [1], although the natural resources and pollution subsystems in the model were modified [9],
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