Cost The projected cost of the project is 30 billion ¥ (200 million US dollars), which does not include the launch costs for 10 Ariane V vehicles (approximately 1.1 billion US dollars). With that, the total projected cost approaches 1.5 billion US dollars. If current prices are used for the transmitting antenna (which dominate the cost of the array in current prices, as illustrated in the next section), then the current costs would be 10-100 times larger. In the mid-term, these costs of the critical components must decrease by those factors in order to achieve even 1 billion US dollars platform cost. Finally, the considerable cost of the rectenna is not included in the above project costs. Notes The first major areas of concern include the difficulty of constructing a platform of this size given the current state of the art as well as the extremely difficult environment. The DDTE costs of a telerobotic servicer is of the order of several 100 million $US. Also, the proximity operations, rendezvous/docking, transfer of the cargo elements into the structure is thought to be demanding. Other points of difficulty include the low mass of the truss structure, the high mass of the cable (though some power conditioning equipment is thought to be included), the 50% mass figure for the transmitting antenna (the heat transfer limit of 798 W/m2 is a factor of five larger), the stability of the platform during construction, and, the cost of maintaining ground control people during the year-plus construction period. In order to reduce costs, conventional a-Si arrays are used. However, these are known to degrade very rapidly in the space environment (by a dramatic drop in efficiency) and may not perform as well as other array choices. Finally, the overall rigidity of the structure is a problem if there are perturbations of the transmitting antenna which cause inaccurate pointing of the microwave beam. General The SPS-2000 study is particularly useful, in that it offers a strawman design of a 1-10 MW class facility with all of the attendant problems. As a quick comparison, though, if one takes the approximate figure of 1 billion US dollars for the cost of a 10MW SPS platform, the result is 100 million US dollars/MW. A fast breeder reactor of the class contemplated by Japan provides 700 MW for 1 trillion ¥ (7 billion US dollars) which results in 10 million US dollars/MW. The price for the SPS-2000 (again, not including DDTE costs) is approximately 10 times the cost of the fast breeder reactor per MW. In addition, the platform would not continuously beam 10 MW to a particular location, but only some fraction of die orbit. This also would increase the cost per continuous MW delivered. On the other hand, once the basic DDTE is complete, the unit costs per SPS platform would diminish. In addition, the same rectenna could be used for several SPS platforms operating in a constellation, further reducing the cost per MW delivered. Table 10.4.5 Concept 1 1MW Mid term Demonstrator
RkJQdWJsaXNoZXIy MTU5NjU0Mg==