2. Description of 5 MWe DSG STPP
The 5 MWe DSG STPP [15,16] is composed of a DSG parabolictrough
solar collector field connected to a superheated steam
Rankine power cycle (Fig. 1). The solar collector field consists of
seven parallel rows of ET-100 collectors and each row is composed
of 10 collectors: 3 collectors for preheating water, 5 collectors for
water evaporation and 2 collectors for superheating steam. Table 1
gives the parameters of the ET-100 parabolic-trough collector and
design-point parameters for the solar collector field. The design
point of solar collector field is solar noon on June 21st. The solar
collector field produces superheated steam at 410 C and 70 bar.
Fig. 2 shows the temperature–entropy plot of plant cycle. The steam
generated from solar collector field enters the high-pressure
turbine (HPT) via pipeline-1 and it is divided in two streams at
outlet to HPT. The one stream is sent to inlet of the low-pressure
turbine (LPT), while another stream is used for feed water heating
and deaeration in a feed water tank/deaerator operated at 5.6 bar.
The exhaust steam from low-pressure turbine is condensed in
steam condenser with the help of cooling water from the cooling
tower. The condensate is pumped by condensate extraction pump
(CEP) to ejector and deaerator. Degasified water is then sent to the
solar collector field inlet through pipeline-2 by the collector feed
water pump (CFP).