Add natural gas plants and expand feedstock capabilities

CHANGELOG.md

@@ -41,8 +41,10 @@
 - Updated finance parameter organization naming in `plant_config`.
 - Added cost model base class and removed `plant_config['finance_parameters']['discount_years']['tech']`. Some cost models require user-input cost year (`tech_config[tech]['model_inputs']['cost_parameters']['cost_year']`) others do not. Cost year is output from cost models as a discrete output.
 - Add ocean alkalinity enhancement technology model.
-- Refactored `ProFastComp` and put in a new file (`h2integrate/core/profast_financial.py`). Added flexibility to allow users to specify different financial models.
 - Added ability to export ProFAST object to yaml file in `ProFastComp`
+- Added `natural_gas_performance` and `natural_gas_cost` models, allowing for natural gas power plant modeling.
+- Revamped the feedstocks technology group to allow for more precise modeling of feedstock supply chains, including capacity constraints and feedstock amount consumed.
+- Refactored `ProFastComp` and put in a new file (`h2integrate/core/profast_financial.py`). Added flexibility to allow users to specify different financial models.
 - Bugfix on `h2integrate/transporters/power_combiner.py` and enabled usage of multiple electricity producing technologies.
 - Updated option to pass variables in technology interconnections to allow for different variable names from source to destination in the format `[source_tech, dest_tech, (source_tech_variable, dest_tech_variable)]`
 - Added `simulation` section under `plant_config['plant']` that has information such as number of timesteps in the simulation, time step interval in seconds, simulation start time, and time zone.

docs/_toc.yml

@@ -20,8 +20,10 @@ parts:
 
 - caption: Technology Models
   chapters:
+  - file: technology_models/feedstocks
   - file: technology_models/run_of_river
   - file: technology_models/direct_ocean_capture
+  - file: technology_models/natural_gas
   - file: technology_models/wombat_electrolyzer_om
   - file: technology_models/pvwattsv8_solar_pv.md
   - file: technology_models/atb_costs_pv.md

docs/technology_models/feedstocks.md

@@ -0,0 +1,81 @@
+# Feedstock Models
+
+Feedstock models in H2Integrate represent any resource input that is consumed by technologies in your plant, such as natural gas, water, electricity from the grid, or any other material input.
+The feedstock modeling approach provides a flexible way to track resource consumption and calculate associated costs for any type of input material or energy source.
+Please see the example `16_natural_gas` in the `examples` directory for a complete setup using natural gas as a feedstock.
+
+## How Feedstock Models Work
+
+### Two-Component Architecture
+
+Each feedstock type requires two model components:
+
+1. **Performance Model** (`feedstock_performance`):
+   - Generates the feedstock supply profile
+   - Outputs `{feedstock_type}_out` variable
+   - Located at the beginning of the technology chain
+
+2. **Cost Model** (`feedstock_cost`):
+   - Calculates consumption costs based on actual usage
+   - Takes `{feedstock_type}_consumed` as input
+   - Located after all consuming technologies in the chain
+
+### Technology Interconnections
+
+Feedstocks connect to consuming technologies through the `technology_interconnections` in your plant configuration. The connection pattern is:
+
+```yaml
+technology_interconnections: [
+    ["name_of_feedstock_source", "consuming_technology", "feedstock_type", "connection_type"],
+]
+```
+
+Where:
+- `name_of_feedstock_source`: Name of your feedstock source
+- `consuming_technology`: Technology that uses the feedstock
+- `feedstock_type`: Type identifier (e.g., "natural_gas", "water", "electricity")
+- `connection_type`: Name for the connection (e.g., "pipe", "cable")
+
+## Configuration
+
+To use the feedstock performance and cost models, add an entry to your `tech_config.yaml` like this:
+
+```yaml
+ng_feedstock:
+    performance_model:
+        model: "feedstock_performance"
+    cost_model:
+        model: "feedstock_cost"
+    model_inputs:
+        shared_parameters:
+        feedstock_type: "natural_gas"
+        units: "MMBtu"
+        performance_parameters:
+        rated_capacity: 100.
+        cost_parameters:
+        cost_year: 2023
+        price: 4.2
+        annual_cost: 0.
+        start_up_cost: 100000.
+```
+
+### Performance Model Parameters
+
+- `feedstock_type` (str): Identifier for the feedstock type (e.g., "natural_gas", "water", "electricity")
+- `units` (str): Units for feedstock consumption (e.g., "MMBtu", "kg", "galUS", "MWh")
+- `rated_capacity` (float): Maximum feedstock supply rate in `units`/hour
+
+### Cost Model Parameters
+
+- `feedstock_type` (str): Must match the performance model identifier
+- `units` (str): Must match the performance model units
+- `price` (float, int, or list): Cost per unit in USD/`units`. Can be:
+  - Scalar: Constant price for all timesteps and years
+  - List: Price per timestep
+- `annual_cost` (float, optional): Fixed cost per year in USD/year. Defaults to 0.0
+- `start_up_cost` (float, optional): One-time capital cost in USD. Defaults to 0.0
+- `cost_year` (int): Dollar year for cost inputs
+
+```{tip}
+The `price` parameter is flexible - you can specify constant pricing with a single value or time-varying pricing with an array of values matching the number of simulation timesteps.
+```

docs/technology_models/natural_gas.md

@@ -0,0 +1,39 @@
+# Natural gas power plant model
+
+The natural gas power plant model simulates electricity generation from natural gas combustion, suitable for both natural gas combustion turbines (NGCT) and natural gas combined cycle (NGCC) plants. The model calculates electricity output based on natural gas input and plant heat rate, along with comprehensive cost modeling that includes capital expenses, operating expenses, and fuel costs.
+
+To use this model, specify `"natural_gas_performance"` as the performance model and `"natural_gas_cost"` as the cost model.
+
+## Performance Parameters
+
+The performance model requires the following parameter:
+
+- `heat_rate` (required): Heat rate of the natural gas plant in MMBtu/MWh. This represents the amount of fuel energy required to produce one MWh of electricity. Lower values indicate higher efficiency. Typical values:
+  - **NGCC (Combined Cycle)**: 6-8 MMBtu/MWh (high efficiency)
+  - **NGCT (Combustion Turbine)**: 10-14 MMBtu/MWh (lower efficiency, faster response)
+
+The model implements the relationship:
+
+$$
+\text{Electricity Output (MW)} = \frac{\text{Natural Gas Input (MMBtu/h)}}{\text{Heat Rate (MMBtu/MWh)}}
+$$
+
+## Cost Parameters
+
+The cost model calculates capital and operating costs based on the following parameters:
+
+- `capex` (required): Capital cost per unit capacity in $/kW. This includes all equipment, installation, and construction costs. Typical values:
+  - **NGCT**: 600-2000 $/kW (lower capital cost)
+  - **NGCC**: 800-2400 $/kW (higher capital cost)
+
+- `fopex` (required): Fixed operating expenses per unit capacity in \$/kW/year. This includes fixed O&M costs that don't vary with generation. Typical values: 5-15 \$/kW/year
+
+- `vopex` (required): Variable operating expenses per unit generation in \$/MWh. This includes variable O&M costs that scale with electricity generation. Typical values: 1-5 \$/MWh
+
+- `heat_rate` (required): Heat rate in MMBtu/MWh, used for fuel cost calculations.
+
+- `ng_price` (required): Natural gas price in $/MMBtu. Can be a numeric value for fixed price or `"variable"` string to indicate external price management.
+
+- `project_life` (optional): Project lifetime in years for cost calculations. Default is 30 years, typical for power plants.
+
+- `cost_year` (required): Dollar year corresponding to input costs.

examples/16_natural_gas/driver_config.yaml

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+name: "driver_config"
+description: "This analysis runs a natural gas power plant"
+
+general:
+  folder_output: outputs

examples/16_natural_gas/natgas.yaml

@@ -0,0 +1,7 @@
+name: "H2Integrate_config"
+
+system_summary: "This reference natural gas plant contains a simple natural gas combined cycle (NGCC) power plant"
+
+driver_config: "driver_config.yaml"
+technology_config: "tech_config.yaml"
+plant_config: "plant_config.yaml"

examples/16_natural_gas/plant_config.yaml

@@ -0,0 +1,64 @@
+name: "plant_config"
+description: "This plant is located in Texas"
+
+site:
+  latitude: 32.34
+  longitude: -98.27
+  elevation_m: 440.0
+  time_zone: -6
+
+  # array of polygons defining boundaries with x/y coords
+  boundaries: [
+    {
+      x: [0.0, 1000.0, 1000.0, 0.0],
+      y: [0.0, 0.0, 100.0, 1000.0],
+    },
+    {
+      x: [2000.0, 2500.0, 2000.0],
+      y: [2000.0, 2000.0, 2500.0],
+    }
+  ]
+
+# array of arrays containing left-to-right technology
+# interconnections; can support bidirectional connections
+# with the reverse definition.
+# in this example the natural gas combined cycle plant is behind-the-meter
+# and not connected to additional technologies.
+# hence the empty array.
+technology_interconnections: [
+    ["ng_feedstock", "natural_gas_plant", "natural_gas", "pipe"],
+]
+
+plant:
+  plant_life: 30
+  grid_connection: False # option, can be turned on or off
+  ppa_price: 0.027498168 # based off correlations of LBNL PPA data
+  hybrid_electricity_estimated_cf: 0.492 #should equal 1 if grid_connection = True
+  simulation:
+    n_timesteps: 8760
+
+finance_parameters:
+  finance_model: "ProFastComp"
+  model_inputs:
+    params:
+      analysis_start_year: 2032
+      installation_time: 36
+      inflation_rate: 0.0
+      discount_rate: 0.09
+      debt_equity_ratio: 2.62
+      property_tax_and_insurance: 0.03
+      total_income_tax_rate: 0.308
+      capital_gains_tax_rate: 0.15
+      sales_tax_rate: 0.07375
+      debt_interest_rate: 0.07
+      debt_type: "Revolving debt"
+      loan_period_if_used: 0
+      cash_onhand_months: 1
+      admin_expense: 0.00
+    capital_items:
+        depr_type: "MACRS"
+        depr_period: 5
+        refurb: [0.]
+  cost_adjustment_parameters:
+    cost_year_adjustment_inflation: 0.025
+    target_dollar_year: 2022

examples/16_natural_gas/run_natural_gas.py

@@ -0,0 +1,11 @@
+from h2integrate.core.h2integrate_model import H2IntegrateModel
+
+
+# Create an H2I model
+h2i = H2IntegrateModel("natgas.yaml")
+
+# Run the model
+h2i.run()
+
+# Post-process the results
+h2i.post_process()

examples/16_natural_gas/tech_config.yaml

@@ -0,0 +1,34 @@
+name: "technology_config"
+description: "This plant produces electricity from natural gas using a combined cycle turbine"
+
+technologies:
+  ng_feedstock:
+    performance_model:
+      model: "feedstock_performance"
+    cost_model:
+      model: "feedstock_cost"
+    model_inputs:
+      shared_parameters:
+        feedstock_type: "natural_gas"
+        units: "MMBtu"
+      performance_parameters:
+        rated_capacity: 100.
+      cost_parameters:
+        cost_year: 2023
+        price: 4.2
+        annual_cost: 0.
+        start_up_cost: 100000.
+  natural_gas_plant:
+    performance_model:
+      model: "natural_gas_performance"
+    cost_model:
+      model: "natural_gas_cost"
+    model_inputs:
+      shared_parameters:
+        heat_rate_mmbtu_per_mwh: 7.5  # MMBtu/MWh - typical for NGCC
+      cost_parameters:
+        plant_capacity_mw: 100.
+        capex_per_kw: 1000  # $/kW - typical for NGCC
+        fixed_opex_per_kw_per_year: 10.0  # $/kW/year
+        variable_opex_per_mwh: 2.5  # $/MWh
+        cost_year: 2023

h2integrate/converters/ammonia/test/test_simple_ammonia_model.py

@@ -7,6 +7,15 @@
 )
 
 
+plant_config = {
+    "plant": {
+        "plant_life": 30,
+        "simulation": {
+            "n_timesteps": 8760,
+        },
+    },
+}
+
 tech_config_dict = {
     "model_inputs": {
         "shared_parameters": {

h2integrate/converters/natural_gas/natural_gas_baseclass.py

@@ -0,0 +1,41 @@
+import openmdao.api as om
+
+
+class NaturalGasPerformanceBaseClass(om.ExplicitComponent):
+    """
+    Base class for natural gas plant performance models.
+
+    This base class defines the common interface for natural gas combustion
+    turbine (NGCT) and natural gas combined cycle (NGCC) performance models.
+    """
+
+    def initialize(self):
+        self.options.declare("driver_config", types=dict)
+        self.options.declare("plant_config", types=dict)
+        self.options.declare("tech_config", types=dict)
+
+    def setup(self):
+        n_timesteps = self.options["plant_config"]["plant"]["simulation"]["n_timesteps"]
+        self.add_input(
+            "natural_gas_in",
+            val=0.0,
+            shape=n_timesteps,
+            units="MMBtu",
+            desc="Natural gas input energy",
+        )
+        self.add_output(
+            "electricity_out",
+            val=0.0,
+            shape=n_timesteps,
+            units="MW",
+            desc="Electricity output from natural gas plant",
+        )
+
+    def compute(self, inputs, outputs):
+        """
+        Computation for the OM component.
+
+        For a template class this is not implemented and raises an error.
+        """
+
+        raise NotImplementedError("This method should be implemented in a subclass.")