generator between the hot water side and the steam side was assumed to be 14°C. The difference between the inlet hot water from the transport network (315°C) and the exit superheated steam (290°C) in the vapor generator was assumed to be 25°C. Within these assumptions the amount of feedwater heating is the primary parameter in establishing the optimum Rankine operating conditions. The net Rankine plant efficiency is shown in Figure 16 versus the amount of feedwater heating (FTR). The temperature of the returning hot water is varied from 200°C to 290°C with a constant inlet temperature of 315°C. The feedwater temperature ratio (FTR) is Choosing the optimum FTR for each returning water temperature, and applying a correction factor of 1.025 for the 23°C dry bulb temperature, the optimum Rankine cycle conditions were determined and are shown below: The above figures are all based on a 290°C turbine inlet temperature. The degree of superheat varies with each point and varies from 6°C to 83°C as exit water temperature varies from 290°C to 200°C. The steam transport subsystem (system 2, Table 6) does not have a separate steam generator since the steam is directly produced in the collectors. The turbine inlet temperature was considered to be 510°C minus the loss of superheat
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