NatLabRockies · johnjasa · Dec 10, 2025 · Oct 17, 2025 · Oct 17, 2025 · Oct 27, 2025
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -35,6 +35,7 @@
 - Improved readability of the postprocessing printout by simplifying numerical representation, especially for years
 - Added grid converter performance and cost model which can be used to buy, sell, or buy and sell electricity to/from the grid
 - Add open-loop load demand controllers: `DemandOpenLoopConverterController` and `FlexibleDemandOpenLoopConverterController`
+- Removed a large portion of the old GreenHEART code that was no longer being used
 
 ## 0.4.0 [October 1, 2025]
 

diff --git a/docs/_toc.yml b/docs/_toc.yml
@@ -39,6 +39,7 @@ parts:
   - file: technology_models/pysam_battery.md
   - file: technology_models/geologic_hydrogen.md
   - file: technology_models/grid
+  - file: technology_models/hydrogen_storage.md
 
 - caption: Resource Models
   chapters:

diff --git a/docs/developer_guide/adding_a_new_technology.md b/docs/developer_guide/adding_a_new_technology.md
@@ -165,13 +165,14 @@ Here's what the updated `supported_models.py` file looks like with our new solar
 from h2integrate.converters.solar.solar_pysam import PYSAMSolarPlantPerformanceComponent
 
 supported_models = {
-    'pysam_solar_plant_performance' : PYSAMSolarPlantPerformanceComponent,
-
-    'pem_electrolyzer_performance': ElectrolyzerPerformanceModel,
-    'pem_electrolyzer_cost': ElectrolyzerCostModel,
-
-    'eco_pem_electrolyzer_performance': ECOElectrolyzerPerformanceModel,
-    'eco_pem_electrolyzer_cost': ECOElectrolyzerCostModel,
+    "pysam_solar_plant_performance" : PYSAMSolarPlantPerformanceComponent,
+
+    "run_of_river_hydro_performance": RunOfRiverHydroPerformanceModel,
+    "run_of_river_hydro_cost": RunOfRiverHydroCostModel,
+    "eco_pem_electrolyzer_performance": ECOElectrolyzerPerformanceModel,
+    "singlitico_electrolyzer_cost": SingliticoCostModel,
+    "basic_electrolyzer_cost": BasicElectrolyzerCostModel,
+    "custom_electrolyzer_cost": CustomElectrolyzerCostModel,
 
     ...
 }

diff --git a/docs/technology_models/hydrogen_storage.md b/docs/technology_models/hydrogen_storage.md
@@ -0,0 +1,49 @@
+# Bulk Hydrogen Storage Cost Model
+
+## Storage Types
+
+H2Integrate models at least three types of bulk hydrogen storage technologies:
+
+- **Underground Pipe Storage**: Hydrogen stored in underground pipeline networks
+- **Lined Rock Caverns (LRC)**: Hydrogen stored in rock caverns with engineered linings
+- **Salt Caverns**: Hydrogen stored in solution-mined salt caverns
+
+These storage options provide different cost-capacity relationships suitable for various scales of hydrogen production and distribution.
+
+## Cost Correlations
+
+The bulk hydrogen storage costs are modeled as functions of storage capacity using exponential correlations:
+
+$$Cost = \exp(a(\ln(m))^2 - b\ln(m) + c)$$
+
+where $m$ is the useable amount of H₂ stored in tonnes.
+
+## Installed Capital Cost and Lifetime Storage Cost
+
+The figures below show how storage costs scale with capacity for different storage technologies:
+
+![Installed capital cost scaling](images/installed_capital_cost_h2.png)
+
+*Figure 1a: Installed capital cost (\$/kg-H₂) as a function of usable hydrogen storage capacity*
+
+![Lifetime storage cost scaling](images/lifetime_storage_cost_h2.png)
+
+*Figure 1b: Lifetime storage cost (\$/kg-H₂-stored) as a function of usable hydrogen storage capacity*
+
+## Cost Correlation Coefficients
+
+### Capital Cost Coefficients (Figure 1a)
+
+| Storage                        | a        | b       | c      |
+|--------------------------------|----------|---------|--------|
+| Underground pipe storage       | 0.004161 | 0.06036 | 6.4581 |
+| Underground lined rock caverns | 0.095803 | 1.5868  | 10.332 |
+| Underground salt caverns       | 0.092548 | 1.6432  | 10.161 |
+
+### Annual Cost Coefficients (Figure 1b)
+
+| Storage                        | a        | b       | c      |
+|--------------------------------|----------|---------|--------|
+| Underground pipe storage       | 0.001559 | 0.03531 | 4.5183 |
+| Underground lined rock caverns | 0.092286 | 1.5565  | 8.4658 |
+| Underground salt caverns       | 0.085863 | 1.5574  | 8.1606 |
diff --git a/docs/technology_models/images/installed_capital_cost_h2.png b/docs/technology_models/images/installed_capital_cost_h2.png
diff --git a/docs/technology_models/images/lifetime_storage_cost_h2.png b/docs/technology_models/images/lifetime_storage_cost_h2.png
diff --git a/docs/user_guide/how_to_set_up_an_analysis.ipynb b/docs/user_guide/how_to_set_up_an_analysis.ipynb
@@ -93,7 +93,6 @@
         "          hydrogen_dmd:\n",
         "        n_clusters: 13\n",
         "        cluster_rating_MW: 40\n",
-        "        pem_control_type: basic\n",
         "        eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol\n",
         "        uptime_hours_until_eol: 77600 #number of 'on' hours until electrolyzer reaches eol\n",
         "        include_degradation_penalty: True #include degradation\n",

diff --git a/docs/user_guide/model_overview.md b/docs/user_guide/model_overview.md
@@ -53,6 +53,10 @@ The inputs, outputs, and corresponding technology that are currently available i
 | `desal`   |  water     | electricity |
 | `natural_gas`   |  electricity     | natural gas |
 
+```{note}
+When the Primary Commodity is electricity, those converters are considered electricity producing technologies and their electricity production is summed for financial calculations.
+```
+
 (transport)=
 ## Transport
 `Transport` models are used to either:
@@ -149,10 +153,8 @@ Below summarizes the available performance, cost, and financial models for each
     - combined performance and cost:
         + `'wombat'`
     - performance models:
-        + `'pem_electrolyzer_performance'`
         + `'eco_pem_electrolyzer_performance'`
     - cost models:
-        + `'pem_electrolyzer_cost'`
         + `'singlitico_electrolyzer_cost'`
         + `'basic_electrolyzer_cost'`
 - `geoh2_well_subsurface`: geologic hydrogen well subsurface

diff --git a/examples/01_onshore_steel_mn/tech_config.yaml b/examples/01_onshore_steel_mn/tech_config.yaml
@@ -29,7 +29,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 18
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000. #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation
@@ -68,102 +67,100 @@ technologies:
       shared_parameters:
         capacity_factor: 0.9
         plant_capacity_mtpy: 1000000.
-
       cost_parameters:
         operational_year: 2035
-        o2_heat_integration: false
+        o2_heat_integration: True
         lcoh: 7.37
-        inflation_rate:
         installation_time: 36 # months
         inflation_rate: 0.0 # 0 for nominal analysis
-        feedstocks:
-          oxygen_market_price: 0.0 # 0.03 $/kgO2 if `o2_heat_integration` == 1
-          unused_oxygen: 395
-          lime_unitcost: 122.1
-          carbon_unitcost: 236.97
-          electricity_cost: 48.92
-          iron_ore_pellet_unitcost: 207.35
-          oxygen_market_price: 0.03
-          raw_water_unitcost: 0.59289
-          iron_ore_consumption: 1.62927
-          raw_water_consumption: 0.80367
-          lime_consumption: 0.01812
-          carbon_consumption: 0.0538
-          hydrogen_consumption: 0.06596
-          natural_gas_consumption: 0.71657
-          electricity_consumption: 0.5502
-          slag_disposal_unitcost: 37.63
-          slag_production: 0.17433
-          maintenance_materials_unitcost: 7.72
-          natural_gas_prices:
-            "2035": 3.76232
-            "2036": 3.776032
-            "2037": 3.812906
-            "2038": 3.9107960000000004
-            "2039": 3.865776
-            "2040": 3.9617400000000003
-            "2041": 4.027136
-            "2042": 4.017166
-            "2043": 3.9715339999999997
-            "2044": 3.924314
-            "2045": 3.903287
-            "2046": 3.878192
-            "2047": 3.845413
-            "2048": 3.813366
-            "2049": 3.77735
-            "2050": 3.766164
-            "2051": 3.766164
-            "2052": 3.766164
-            "2053": 3.766164
-            "2054": 3.766164
-            "2055": 3.766164
-            "2056": 3.766164
-            "2057": 3.766164
-            "2058": 3.766164
-            "2059": 3.766164
-            "2060": 3.766164
-            "2061": 3.766164
-            "2062": 3.766164
-            "2063": 3.766164
-            "2064": 3.766164
-        finances:
-          # plant_life: 30
-          grid_prices:
-            "2035": 89.42320514456621
-            "2036": 89.97947569251141
-            "2037": 90.53574624045662
-            "2038": 91.09201678840184
-            "2039": 91.64828733634704
-            "2040": 92.20455788429224
-            "2041": 89.87291235917809
-            "2042": 87.54126683406393
-            "2043": 85.20962130894978
-            "2044": 82.87797578383562
-            "2045": 80.54633025872147
-            "2046": 81.38632144593608
-            "2047": 82.22631263315068
-            "2048": 83.0663038203653
-            "2049": 83.90629500757991
-            "2050": 84.74628619479452
-            "2051": 84.74628619479452
-            "2052": 84.74628619479452
-            "2053": 84.74628619479452
-            "2054": 84.74628619479452
-            "2055": 84.74628619479452
-            "2056": 84.74628619479452
-            "2057": 84.74628619479452
-            "2058": 84.74628619479452
-            "2059": 84.74628619479452
-            "2060": 84.74628619479452
-            "2061": 84.74628619479452
-            "2062": 84.74628619479452
-            "2063": 84.74628619479452
-            "2064": 84.74628619479452
-
-          # Additional parameters passed to ProFAST
-          financial_assumptions:
-            "total income tax rate": 0.2574
-            "capital gains tax rate": 0.15
-            "leverage after tax nominal discount rate": 0.10893
-            "debt equity ratio of initial financing": 0.624788
-            "debt interest rate": 0.050049
+        # Feedstock parameters (flattened)
+        excess_oxygen: 395
+        lime_unitcost: 122.1
+        lime_transport_cost: 0.0
+        carbon_unitcost: 236.97
+        carbon_transport_cost: 0.0
+        electricity_cost: 48.92
+        iron_ore_pellet_unitcost: 207.35
+        iron_ore_pellet_transport_cost: 0.0
+        oxygen_market_price: 0.03
+        raw_water_unitcost: 0.59289
+        iron_ore_consumption: 1.62927
+        raw_water_consumption: 0.80367
+        lime_consumption: 0.01812
+        carbon_consumption: 0.0538
+        hydrogen_consumption: 0.06596
+        natural_gas_consumption: 0.71657
+        electricity_consumption: 0.5502
+        slag_disposal_unitcost: 37.63
+        slag_production: 0.17433
+        maintenance_materials_unitcost: 7.72
+        natural_gas_prices:
+          "2035": 3.76232
+          "2036": 3.776032
+          "2037": 3.812906
+          "2038": 3.9107960000000004
+          "2039": 3.865776
+          "2040": 3.9617400000000003
+          "2041": 4.027136
+          "2042": 4.017166
+          "2043": 3.9715339999999997
+          "2044": 3.924314
+          "2045": 3.903287
+          "2046": 3.878192
+          "2047": 3.845413
+          "2048": 3.813366
+          "2049": 3.77735
+          "2050": 3.766164
+          "2051": 3.766164
+          "2052": 3.766164
+          "2053": 3.766164
+          "2054": 3.766164
+          "2055": 3.766164
+          "2056": 3.766164
+          "2057": 3.766164
+          "2058": 3.766164
+          "2059": 3.766164
+          "2060": 3.766164
+          "2061": 3.766164
+          "2062": 3.766164
+          "2063": 3.766164
+          "2064": 3.766164
+        # Financial parameters (flattened)
+        grid_prices:
+          "2035": 89.42320514456621
+          "2036": 89.97947569251141
+          "2037": 90.53574624045662
+          "2038": 91.09201678840184
+          "2039": 91.64828733634704
+          "2040": 92.20455788429224
+          "2041": 89.87291235917809
+          "2042": 87.54126683406393
+          "2043": 85.20962130894978
+          "2044": 82.87797578383562
+          "2045": 80.54633025872147
+          "2046": 81.38632144593608
+          "2047": 82.22631263315068
+          "2048": 83.0663038203653
+          "2049": 83.90629500757991
+          "2050": 84.74628619479452
+          "2051": 84.74628619479452
+          "2052": 84.74628619479452
+          "2053": 84.74628619479452
+          "2054": 84.74628619479452
+          "2055": 84.74628619479452
+          "2056": 84.74628619479452
+          "2057": 84.74628619479452
+          "2058": 84.74628619479452
+          "2059": 84.74628619479452
+          "2060": 84.74628619479452
+          "2061": 84.74628619479452
+          "2062": 84.74628619479452
+          "2063": 84.74628619479452
+          "2064": 84.74628619479452
+        # Financial assumptions
+        financial_assumptions:
+          "total income tax rate": 0.2574
+          "capital gains tax rate": 0.15
+          "leverage after tax nominal discount rate": 0.10893
+          "debt equity ratio of initial financing": 0.624788
+          "debt interest rate": 0.050049
diff --git a/examples/02_texas_ammonia/tech_config.yaml b/examples/02_texas_ammonia/tech_config.yaml
@@ -29,7 +29,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 16
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 10 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000 #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/03_methanol/co2_hydrogenation/tech_config_co2h.yaml b/examples/03_methanol/co2_hydrogenation/tech_config_co2h.yaml
@@ -28,7 +28,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 4
         cluster_rating_MW: 39
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 10 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000 #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/03_methanol/co2_hydrogenation_doc/tech_config_co2h.yaml b/examples/03_methanol/co2_hydrogenation_doc/tech_config_co2h.yaml
@@ -36,7 +36,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 4
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 10 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000 #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/05_wind_h2_opt/tech_config.yaml b/examples/05_wind_h2_opt/tech_config.yaml
@@ -45,7 +45,6 @@ technologies:
           hydrogen_dmd:
         cluster_rating_MW: 20
         n_clusters: 25
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000. #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/08_wind_electrolyzer/tech_config.yaml b/examples/08_wind_electrolyzer/tech_config.yaml
@@ -46,7 +46,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 13 #should be 12.5 to get 500 MW
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000. #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/10_electrolyzer_om/tech_config.yaml b/examples/10_electrolyzer_om/tech_config.yaml
@@ -44,7 +44,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 1
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000. #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/12_ammonia_synloop/tech_config.yaml b/examples/12_ammonia_synloop/tech_config.yaml
@@ -29,7 +29,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 16
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 10 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000 #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/14_wind_hydrogen_dispatch/inputs/tech_config.yaml b/examples/14_wind_hydrogen_dispatch/inputs/tech_config.yaml
@@ -45,7 +45,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 18
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000. #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation

diff --git a/examples/15_wind_solar_electrolyzer/tech_config.yaml b/examples/15_wind_solar_electrolyzer/tech_config.yaml
@@ -81,7 +81,6 @@ technologies:
           hydrogen_dmd:
         n_clusters: 18
         cluster_rating_MW: 40
-        pem_control_type: 'basic'
         eol_eff_percent_loss: 13 #eol defined as x% change in efficiency from bol
         uptime_hours_until_eol: 80000. #number of 'on' hours until electrolyzer reaches eol
         include_degradation_penalty: True #include degradation