8. Plant Finance Example

Using the plant finance model only requires a short script. The plant finance model depends on the costs of the turbine, balance of station, expected operational expenditures, energy production and a few financial parameters. This example shows some representative values for the financial parameters, including a fixed charge rate for COE, the construction financing charge rate, the tax rate for OPEX tax deductions, the time for plant construction, the project lifetime and the sea depth (which would be 0.0 for a land-based plant). In a full turbine analysis, some of these input values come from upstream components or from the turbine design.

#!/usr/bin/env python3

# Import the libraries
import openmdao.api as om

from wisdem.plant_financese.plant_finance import PlantFinance

# Initialize the OpenMDAO instance
mygroup = om.Group()
mygroup.add_subsystem("main", PlantFinance(), promotes=["*"])

prob = om.Problem(reports=False)
prob.model = mygroup
prob.setup()

# Set variable inputs with intended units
prob.set_val("machine_rating", 2.32e3, units="kW")
prob.set_val("tcc_per_kW", 1093, units="USD/kW")
prob.set_val("turbine_number", 87)
prob.set_val("opex_per_kW", 43.56, units="USD/kW/yr")
prob.set_val("fixed_charge_rate", 0.079216644)
prob.set_val("bos_per_kW", 517.0, units="USD/kW")
prob.set_val("wake_loss_factor", 0.15)
prob.set_val("turbine_aep", 9915.95e3, units="kW*h")

# Run the model once
prob.run_model()

# Print all inputs and outputs to the screen
prob.model.list_inputs(units=True)
prob.model.list_outputs(units=True)

The screen output is,

10 Input(s) in 'model'
----------------------

varname            value         units
-----------------  ------------  -----------
machine_rating     [2320.]       kW
tcc_per_kW         [1093.]       USD/kW
offset_tcc_per_kW  [0.]          USD/kW
bos_per_kW         [517.]        USD/kW
opex_per_kW        [43.56]       USD/kW/yr
park_aep           [0.]          kW*h
turbine_aep        [9915950.]    kW*h
wake_loss_factor   [0.15]        None
fixed_charge_rate  [0.07921664]  None
turbine_number     87.0          Unavailable


2 Explicit Output(s) in 'model'
-------------------------------

varname    value             units
---------  ----------------  --------
lcoe       [0.04709575]      USD/kW/h
plant_aep  [7.33284502e+08]  USD/kW/h