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

L
FEP = 0.0
TPRE = 1.0 hour
TSTRT = 1.0 hour
PARLl = 0.5
PARL2 = 0.103
PARL3 = 0.5
PARL4 = 0.103
PARL5 = 0.5
PARLG = 0.008
PARL7 = 0.5
PARL8 = 0.008
PARL9 = 0.18
. PARLlO = 0.009
1II.H. Energy Calculation During a Performance Run
A system is designed by DELSOL to have a certain power rating at a fixed
point in time. Further, DELSOL calculates the field efficiencies at times through-
out the year as defined by the variables NYEAR and HRDEL. However, the cri-
terion by which DELSOL chooses an optimum system is that of lowest levelized
energy cost, which is a function of equipment costs and of the net annual en-
ergy output of the plant. (Costs will be discussed in Chapter V.) Annual energy
is calculated in two ways in DELSOL, oncd as an approximation for use in sys-
tem optimization and once in detail vs. time in a final performance calculation
(IPROB=O). A sample waterfall chart, without values, is shown in Figure 111-4 to
indicate the bookkeeping which DELSOL does to calculate annual energy.
For either an initial performance run for use in system optimization or a final
performance run (IPROB=4 or 0) the code calculates the hours of receiver oper-
ation (HROP) and annual insolation based on the values of ASTART, WEATH,
and INSOL. Next, field efficiencies are calculated for each time HRDEL over each
day NYEAR. From this point on, annual energy is calculated during system op-
timization by using yearly insolation to calculate annual energy to the receiver
and then using that value to subtract out receiver losses (Equation 1II.G-11) and
piping losses (Equation 1II.G-18). Storage is assumed to be large enough to store
any excess energy during optimization, so that none is discarded. Next, the tur-
bine is assumed always to run at off-design conditions for optimization, having
an average annual conversion efficiency of ETAREFxFEFF. This is probably the
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