Other costing assumptions include a 30-year operating lifetime, a 92% plant factor for 2.45 GHz operation, a 15% rate of return on investment capital, and a 17% increase in net SPS hardware costs to account for mass growth. The cost statements for the individual subsystems may be further divided as shown in Table 1 for the reference satellite. Proportionality factors are used to rescale costs and masses for alternative configurations, e.g., P signifies normalized transmit power; the solar cell blankets have costs and masses proportional to the amount of power transmitted. The nomenclature for each proportionality factor is given in the diagram. The information in Table 1 can be reduced into the following comprehensive SPS cost equation: where Cref is the cost for the 1978 reference design SPS; P is the transmit pow- er/reference, 6.7 GW; A is the antenna area/reference, 0.7854 km2; R is the rectenna area/reference, 78.54 km2; Ma is the power transmission (antenna) mass/13,627 MT; C„o is the total satellite hardware cost, $4947 x 106; Ch is the satellite hardware cost less amortization, $4474 x 106.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==