ED Cost Documentation

docs/technical_reference/costing/electrodialysis.rst

@@ -9,7 +9,13 @@ The following parameters are constructed for the unit on the FlowsheetCostingBlo
 .. csv-table::
    :header: "Description", "Symbol", "Parameter Name", "Default Value", "Units"
 
-   "description", ":math:`Symbol_{example}`", "``parameter_name``", "1", ":math:`\text{dimensionless}`"
+   "Membrane unit cost", ":math:`C_{mem}`", "``membrane_capital_cost``", "160", ":math:`\text{USD}_{2018}\text{/m}^2`"
+   "Membrane replacement factor (fraction of membrane replaced/year)", ":math:`f_{mem,\, replace}`", "``factor_membrane_replacement``", "0.2", ":math:`\text{yr}^{-1}`"
+   "Electrode unit cost", ":math:`C_{elec}`", "``stack_electrode_capital_cost``", "2100", ":math:`\text{USD}_{2018}\text{/m}^2`"
+   "Electrode replacement factor (fraction of electrode replaced/year)", ":math:`f_{elec,\, replace}`", "``factor_stack_electrode_replacement``", "0.2", ":math:`\text{yr}^{-1}`"
+   "Rectifier cost coefficient, a", ":math:`a_{rectifier}`", "``rectifier_cost_coeff[0]``", "508.6", ":math:`\text{dimensionless}`"
+   "Rectifier cost coefficient, b", ":math:`b_{rectifier}`", "``rectifier_cost_coeff[1]``", "2810", ":math:`\text{dimensionless}`"
+   "AC to DC conversion efficiency", ":math:`\eta_{AC-DC}`", "``ac_dc_conversion_efficiency``", "0.9", ":math:`\text{dimensionless}`"
 
 Costing Method Variables
 ++++++++++++++++++++++++
@@ -19,41 +25,45 @@ The following variables are constructed on the unit block (e.g., m.fs.unit.costi
 .. csv-table::
    :header: "Description", "Symbol", "Variable Name", "Index", "Units"
 
-   "description", ":math:`Symbol_{example}`", "``variable_name``", "[t]", ":math:`\text{dimensionless}`"
+   "Cell pair number in a stack", ":math:`n_{pair}`", "``cell_pair_num``", "None", ":math:`\text{dimensionless}`"
+   "Cell width", ":math:`w`", "``cell_width``", "None", ":math:`\text{m}`"
+   "Cell length", ":math:`l`", "``cell_length``", "None", ":math:`\text{m}`"
+   "Power", ":math:`P`", "``power``", "[t]", ":math:`\text{kW}`"
 
 Capital Cost Calculations
 +++++++++++++++++++++++++
 
-Describe capital costs..keep it concise where possible
+Capital cost is dependent upon the cell pair number, cell width, and cell length, as shown in the equations below.
+
+If the system has a rectifier (``has_rectifier=True``):
 
     .. math::
 
-        C_{cap,tot} = C_{cap,example1}+C_{cap,example2}+C_{cap,other}
+        C_{rectifier} = b_{rectifier} + (a_{rectifier} * P / \eta_{AC-DC})
+
+        C_{cap,tot} = (C_{mem} * 2 * n_{pair} * w * l) + (C_{elec} * 2 * w * l) + C_{rectifier}
+
+Otherwise:
 
     .. math::
 
-        C_{cap,example1} = fill in equation for each component in total capex equation
+        C_{cap,tot} = (C_{mem} * 2 * n_{pair} * w * l) + (C_{elec} * 2 * w * l)
 
 
 Operating Cost Calculations
 +++++++++++++++++++++++++++
 
-Describe operating/maintenance costs..keep it concise where possible
+Electricity :math:`C_{elec}` is a variable operating cost based on the energy intensity :math:`E` of the unit process
+(power for electrodialysis), electricity price :math:`P`, electricity flow :math:`Q`, and the plant
+utilization factor :math:`f_{util}`. If a rectifier is included, the energy intensity is the power required for the rectifier.
+The annual electricity costs are calculated as:
 
     .. math::
 
-        C_{op,tot} = C_{op,example1}+C_{op,example2}+C_{op,other}
-
-    .. math::
-
-        C_{op,example1} = fill in equation for each component in total opex equation
+        C_{op, tot} = C_{elec} = E Q f_{util} P
 
 
 Code Documentation
 ------------------
 
 * :mod:`watertap.costing.unit_models.electrodialysis`
-
-References
-----------
-Aim to include at least one reference in most cases, but delete this section if no references used for cost relationships/default values

watertap/costing/unit_models/electrodialysis.py

@@ -23,7 +23,7 @@ def build_electrodialysis_cost_param_block(blk):
     # The following costing itemization and values are referenced to "Desalination 452 (2019) 265–278"
     blk.membrane_capital_cost = pyo.Var(
         initialize=160,
-        doc="Membrane and capitcal costs in [US$/m^2-membrane-area]",
+        doc="Membrane and capital costs in [US$/m^2-membrane-area]",
         units=pyo.units.USD_2018 / (pyo.units.meter**2),
     )
 
@@ -33,7 +33,7 @@ def build_electrodialysis_cost_param_block(blk):
         units=pyo.units.year**-1,
     )
 
-    blk.stack_electrode_captical_cost = pyo.Var(
+    blk.stack_electrode_capital_cost = pyo.Var(
         initialize=2100,
         doc="Electrode cost in [US$/m^2-electrode-area] ",
         units=pyo.units.USD_2018 / (pyo.units.meter**2),
@@ -102,7 +102,7 @@ def cost_electrodialysis_stack(blk):
                         * blk.unit_model.cell_width
                         * blk.unit_model.cell_length
                     )
-                    + blk.costing_package.electrodialysis.stack_electrode_captical_cost
+                    + blk.costing_package.electrodialysis.stack_electrode_capital_cost
                     * (2 * blk.unit_model.cell_width * blk.unit_model.cell_length),
                     to_units=blk.costing_package.base_currency,
                 )
@@ -121,7 +121,7 @@ def cost_electrodialysis_stack(blk):
                     * blk.unit_model.cell_width
                     * blk.unit_model.cell_length
                 )
-                + blk.costing_package.electrodialysis.stack_electrode_captical_cost
+                + blk.costing_package.electrodialysis.stack_electrode_capital_cost
                 * (2 * blk.unit_model.cell_width * blk.unit_model.cell_length),
                 to_units=blk.costing_package.base_currency,
             )
@@ -138,7 +138,7 @@ def cost_electrodialysis_stack(blk):
                 * blk.unit_model.cell_length
             )
             + blk.costing_package.electrodialysis.factor_stack_electrode_replacement
-            * blk.costing_package.electrodialysis.stack_electrode_captical_cost
+            * blk.costing_package.electrodialysis.stack_electrode_capital_cost
             * (2 * blk.unit_model.cell_width * blk.unit_model.cell_length),
             to_units=blk.costing_package.base_currency
             / blk.costing_package.base_period,

watertap/costing/util.py

@@ -217,7 +217,7 @@ def cost_rectifier(blk, power=100 * pyo.units.kW, ac_dc_conversion_efficiency=0.
         )
     )
 
-    # cost electicity flow
+    # cost electricity flow
     blk.costing_package.cost_flow(blk.ac_power, "electricity")