A User's Manual for DELSOL3 - prod.sandia.gov - Sandia National ...

.
sodium systems all energy from the receiver goes through storage before going to
the electric generating equipment. The default value is consistent with a molten
nitrate salt storage:
EFFSTR = 1.0
III. G-8. Parasitic Loads-The power rating and net yearly energy production
of the plant include parasitic load factors (PI,). At the design point:
For system optimization purposes over the year:
where K W-HR,,,, includes an assumed weather outage.
This algorithm does not work well in calculating parasitic losses for systems
with different solar multiples, since for that case the design point gross electric
power and thus parasitic losses could be constant between different systems.
It is assumed that all energy from the receiver will be routed to storage, and
that all energy to the turbine will come from storage. This means that the oper-
ating parasitic fraction REFPRL (Namelist NLEFF) should include parasitics as-
sociated with operating storage as well as operating the receiver and EPGS equip-
ment. The only time at which REFPRL is not applicable is when, at the end of
a day, the receiver shuts down and yet the turbine keeps operating from the en-
ergy remaining in storage. In this case, the parasitic fraction REFPRL is reduced
to the fraction FSP, where FSP is the fraction of parasitic losses not attributable
to field and receiver operation. This is the reason why PLREF and PLAVG differ
from each other. Assuming that storage only operation requires this fraction fs
(FSP) of the design point parasitic load, then
where HrREc = hrs/day of receiver operation
= HROP/365
HrSTOR = hrs/day of storage operation (receiver shut down)
- Energy stored -
MW+..~~,,,,/VTE.~ EF
(llI.G - 23)
The amount of energy stored is dependent on the size of the storage tank(s).
Section V.A-8 discusses in detail how storage is sized.
87