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

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V. System Costs and Economics
While DELSOL can be used to calculate field performance only, it also has
capabilities for total system design. In DELSOL, an optimized system design is
that combination of tower height, receiver size, and field layout which gives the
lowest calculated system energy cost at a given design power level and solar mul-
tiple. In order to calculate the energy cost, both system performance and system
capital and operating costs must be determined. The latter is only done during
the optimization procedure; therefore, annual performance cannot be done on a
system which is input by the user, since costs are unavailable. The subsystem
cost models for estimating the total capital cost and the economic model for cal-
culating the levelized energy cost are discussed below. It is strongly suggested
that the user carefully examine both the cost calculation procedures
and the default values used in those calculations to verify that the re-
sulting component costs will be appropriate for the system being exam-
ined. Different systems and different technologies will almost certainly require
modification of at least some of the reference system values discussed herein and
used by DELSOL.
The units used in DELSOL input must be those specified for the individual
variables, such as meters for all dimensions and dollars for all costs. The user
should be aware that the output from DELSOL is not necessarily consistent in
the units which are used. Specifically, land area might be in either m2 or km2
and annual energy might be in KWhe or MWh,, depending on the location in the
output. Further, energy costs are quoted in mills/KWh,, not cents/KWhe. Al-
though the values will be consistent with the labels, the user should be careful to
note the correct specified units associated with any output value.
V.A. Total Cost Model
The total capital cost, CCT, is calculated as the sum of the costs of several
subsystems adjusted by a factor for uncertainties and miscellaneous expenses:
CCT =(CCH&L $- CCLAND + CCwInE
+ CCTOW + CCnE(:
+ CC!rIlMP + CCpIPE + CCST, IRA~:E CCHTXSTOR + C!CHTX(:H(: + CCEP(:S
+ CcFlXED)
x (1.0 + DI + CONT + SYTS)
(V.A - 1)
As discussed in detail in Chapter 4, the optimization scheme considers one
tower height/receiver size combination at a time and then builds up the heliostat
field zone by zone until the desired power level(s) at the specified solar multiple is
,
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