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S. Casimiro et al. / Desalination and Water Treatment 61 (2017) 183–195 195

is slightly lower than overall specific energy consumption P — Permeate pressure (bar)
p
of the RO plant (3.79 kWh m ) which highly depends on ΔP — Membrane pressure gradient (bar)
–3
the salinity of the input water. Though the overall cutback Q c — Concentrate flow rate (m h )
–1
3
of electrical production of the MED plant corresponds to Q — Feed flow rate (m h )
3
–1
9.07 kWh/m . Q f p — Permeate flow rate (m h )
–3
3
–1
From the analysis above, the electricity yield of the CSP- Q — Average concentrate side flow rate (m h )
3
–1
MED is considerably lower when compared with CSP+RO. R fc — Recovery rate (-)
This is due to the high cold end temperature of the steam tur- R — Membrane rejection rate (-)
bine which results in the delivery of less mechanical work to T j — Feed temperature (°C)
the power generator, when compared to a case using a steam TCF — Temperature correction factor (-)
turbine with a lower cold end temperature (as it happens Δπ — Osmotic pressure gradient (bar)
with the CSP+RO). In order to produce the water amount π — Average concentrate side osmotic pressure (bar)
equal to the full scale plant found at Trapani (that operates π ave — Feed osmotic pressure (bar)
near design capacity during the year if necessary), the solar π f — Permeate osmotic pressure (bar)
desalination systems simulated in this work would need to p
have more than double of the installed capacity.
During the execution of this work it was also possible
to validate the ROSA model with data from an existing RO References
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f