Added variable o&m (#235)

* added variable into cost and finance models

* added plant life input to cost model tests that were missing it

* added varom output to wombat model

* updated CostModelBaseClass doc string

* updated changelog

* added initial test for variable om in profast and updated profast script

* updated added finance tests

* updated units in new finance tests

* added plant life to test plant configs

* updated feedstock cost model and natgas test

* fixed failing tests in feedstock and custom elec cost

* updated variable om tests in test_finance.py

* renamed attr_filter

* Using create_years_of_operation in tests

* Naming fix

* Fixing order of args

* Mods due to review feedback

---------

Co-authored-by: John Jasa <johnjasa11@gmail.com>

Author: elenya-grant

CHANGELOG.md

@@ -51,6 +51,7 @@
 - Added `"custom_electrolyzer_cost"` model, an electrolyzer cost model that allows for user-defined capex and opex values
 - Made `pipe` and `cable` substance-agnostic rather than hard-coded for `hydrogen` and `electricity`
 - Change finance handling to use `finance_subgroups` and `finance_groups` defined in the `plant_config` rather than previous `financial_groups` in the `tech_config` and `technologies_to_include_in_metrics` in `plant_config`
+- Added variable O&M to `CostModelBaseClass` and integrated into finance-related models
 - Added generic storage model, useful for battery, hydrogen, CO2, or other resource storage.
 - Added wind resource model, API baseclasses, updated examples, and documentation.
 

h2integrate/converters/ammonia/test/test_simple_ammonia_model.py

@@ -42,10 +42,11 @@
 
 def test_simple_ammonia_performance_model():
     plant_info = {
+        "plant_life": 30,
         "simulation": {
             "n_timesteps": 2,
             "dt": 3600,
-        }
+        },
     }
 
     prob = om.Problem()
@@ -67,10 +68,11 @@ def test_simple_ammonia_performance_model():
 
 def test_simple_ammonia_cost_model(subtests):
     plant_info = {
+        "plant_life": 30,
         "simulation": {
             "n_timesteps": 8760,
             "dt": 3600,
-        }
+        },
     }
 
     prob = om.Problem()

h2integrate/converters/hydrogen/test/test_custom_electrolyzer_cost_model.py

@@ -22,6 +22,7 @@ def test_custom_electrolyzer_cost_model(subtests):
 
     plant_config = {
         "plant": {
+            "plant_life": 30,
             "simulation": {
                 "n_timesteps": 8760,  # Default number of timesteps for the simulation
             },

h2integrate/converters/hydrogen/wombat_model.py

@@ -40,10 +40,17 @@ def setup(self):
         self.config = WOMBATModelConfig.from_dict(
             merge_shared_inputs(self.options["tech_config"]["model_inputs"], "performance")
         )
-
+        plant_life = int(self.options["plant_config"]["plant"]["plant_life"])
         self.add_output("capacity_factor", val=0.0, units=None)
         self.add_output("CapEx", val=0.0, units="USD", desc="Capital expenditure")
         self.add_output("OpEx", val=0.0, units="USD/year", desc="Operational expenditure")
+        self.add_output(
+            "VarOpEx",
+            val=0.0,
+            shape=plant_life,
+            units="USD/year",
+            desc="Variable operational expenditure",
+        )
         self.add_discrete_output("cost_year", val=0, desc="Dollar year for costs")
         self.add_output(
             "percent_hydrogen_lost",

h2integrate/converters/nitrogen/test/test_simple_asu_model.py

@@ -7,6 +7,7 @@
 
 plant_config = {
     "plant": {
+        "plant_life": 30,
         "simulation": {
             "n_timesteps": 8760,  # Default number of timesteps for the simulation
         },

h2integrate/converters/solar/test/test_pysam_with_atb_costs.py

@@ -132,10 +132,11 @@ def test_utility_pv_cost(
     }
 
     plant_info = {
+        "plant_life": 30,
         "simulation": {
             "n_timesteps": 8760,
             "dt": 3600,
-        }
+        },
     }
 
     prob = om.Problem()
@@ -189,10 +190,11 @@ def test_commercial_pv_cost(
     }
 
     plant_info = {
+        "plant_life": 30,
         "simulation": {
             "n_timesteps": 8760,
             "dt": 3600,
-        }
+        },
     }
 
     prob = om.Problem()
@@ -243,10 +245,11 @@ def test_residential_pv_cost(
     }
 
     plant_info = {
+        "plant_life": 30,
         "simulation": {
             "n_timesteps": 8760,
             "dt": 3600,
-        }
+        },
     }
 
     prob = om.Problem()

h2integrate/core/feedstocks.py

@@ -92,4 +92,5 @@ def compute(self, inputs, outputs, discrete_inputs, discrete_outputs):
         cost_per_year = sum(price * hourly_consumption)
 
         outputs["CapEx"] = self.config.start_up_cost
-        outputs["OpEx"] = self.config.annual_cost + cost_per_year
+        outputs["OpEx"] = self.config.annual_cost
+        outputs["VarOpEx"] = cost_per_year

h2integrate/core/h2integrate_model.py

@@ -751,6 +751,9 @@ def connect_technologies(self):
                     self.plant.connect(
                         f"{tech_name}.OpEx", f"finance_subgroup_{group_id}.opex_{tech_name}"
                     )
+                    self.plant.connect(
+                        f"{tech_name}.VarOpEx", f"finance_subgroup_{group_id}.varopex_{tech_name}"
+                    )
                     self.plant.connect(
                         f"{tech_name}.cost_year",
                         f"finance_subgroup_{group_id}.cost_year_{tech_name}",

h2integrate/core/model_baseclasses.py

@@ -7,7 +7,8 @@ class CostModelBaseClass(om.ExplicitComponent):
 
     Outputs:
         - CapEx (float): capital expenditure costs in $
-        - OpEx (float): annual operating expenditure costs in $/year
+        - OpEx (float): annual fixed operating expenditure costs in $/year
+        - VarOpEx (float): annual variable operating expenditure costs in $/year
 
     Discrete Outputs:
         - cost_year (int): dollar-year corresponding to CapEx and OpEx values.
@@ -20,15 +21,17 @@ def initialize(self):
         self.options.declare("tech_config", types=dict)
 
     def setup(self):
+        plant_life = int(self.options["plant_config"]["plant"]["plant_life"])
         # Define outputs: CapEx and OpEx costs
         self.add_output("CapEx", val=0.0, units="USD", desc="Capital expenditure")
+        self.add_output("OpEx", val=0.0, units="USD/year", desc="Fixed operational expenditure")
         self.add_output(
-            "OpEx",
+            "VarOpEx",
             val=0.0,
+            shape=plant_life,
             units="USD/year",
-            desc="Total (fixed and variable) operational expenditure",
+            desc="Variable operational expenditure",
         )
-
         # Define discrete outputs: cost_year
         self.add_discrete_output(
             "cost_year", val=self.config.cost_year, desc="Dollar year for costs"

h2integrate/core/test/test_feedstocks.py

@@ -100,7 +100,7 @@ def test_single_feedstock_natural_gas(self):
 
         # Check outputs
         capex = prob_cost.get_val("feedstock_cost.CapEx")[0]
-        opex = prob_cost.get_val("feedstock_cost.OpEx")[0]
+        opex = prob_cost.get_val("feedstock_cost.VarOpEx")[0]
 
         self.assertEqual(capex, 100000.0)  # start_up_cost
         expected_opex = 0.0 + 4.2 * consumption.sum()  # annual_cost + price * consumption
@@ -235,7 +235,7 @@ def test_variable_pricing(self):
         prob.run_model()
 
         # Check that OpEx reflects variable pricing
-        opex = prob.get_val("feedstock_cost.OpEx")[0]
+        opex = prob.get_val("feedstock_cost.VarOpEx")[0]
         expected_opex = 0.0 + np.sum(hourly_prices * consumption)
         self.assertAlmostEqual(opex, expected_opex, places=5)