Merge 3dfeb76 into fb1c5f7

src/oemof/solph/_models.py

@@ -383,6 +383,7 @@ def __init__(self, energysystem, discount_rate=None, **kwargs):
             self._set_discount_rate_with_warning()
         else:
             pass
+        self._fix_investments = False
         super().__init__(energysystem, **kwargs)
 
     def _set_discount_rate_with_warning(self):
@@ -521,3 +522,16 @@ def _add_parent_block_variables(self):
                 if (o, i) in self.UNIDIRECTIONAL_FLOWS:
                     for p, t in self.TIMEINDEX:
                         self.flow[o, i, p, t].setlb(0)
+
+    def fix_investments(self):
+        """Fix investment results of an already solved model"""
+        if self.solver_results is None:
+            msg = (
+                "Cannot fix investments as model has not yet been solved!\n"
+                "You have to first solve your model and then call method "
+                "`fix_investments()` on your model instance."
+            )
+            raise ValueError(msg)
+        self._fix_investments = True
+        if hasattr(self, "InvestmentFlowBlock"):
+            self.InvestmentFlowBlock.fix_investments_results()

src/oemof/solph/flows/_investment_flow_block.py

@@ -1175,3 +1175,15 @@ def _max_invest_rule(_):
         self.maximum_rule_build = BuildAction(rule=_max_invest_rule)
 
         return self.maximum_rule
+
+    def fix_investments_results(self):
+        """Fix investments if `_fix_investments` is set to True for model"""
+        m = self.parent_block()
+        for i, o in self.INVESTFLOWS:
+            for p in m.PERIODS:
+                self.invest[i, o, p].fix()
+                self.total[i, o, p].fix()
+                if m.es.periods is not None:
+                    self.old[i, o, p].fix()
+                    self.old_end[i, o, p].fix()
+                    self.old_exo[i, o, p].fix()

tests/constraint_tests.py

@@ -1995,3 +1995,37 @@ def test_storage_level_constraint(self):
             output_levels={out_0: 1 / 8, out_1: 1 / 2},
         )
         self.compare_lp_files("storage_level_constraint.lp", my_om=om)
+
+    def test_investment_fixed(self):
+        """test a repeated solve with fixed investments"""
+        bgas = solph.buses.Bus(label="gas")
+        bel = solph.buses.Bus(label="electricity")
+
+        source = solph.components.Source(
+            label="gas_source",
+            outputs={bgas: solph.flows.Flow()},
+        )
+        converter = solph.components.Converter(
+            label="powerplant_gas",
+            inputs={bgas: solph.flows.Flow()},
+            outputs={
+                bel: solph.flows.Flow(
+                    variable_costs=50,
+                    nominal_value=solph.Investment(maximum=1000, ep_costs=20),
+                )
+            },
+            conversion_factors={bel: 0.58},
+        )
+        sink = solph.components.Sink(
+            label="electricity_consumption",
+            inputs={
+                bel: solph.flows.Flow(nominal_value=100, fix=[0.8, 0.9, 1.0])
+            },
+        )
+        self.energysystem.add(bgas, bel, source, converter, sink)
+        om = solph.Model(self.energysystem)
+        self.compare_lp_files("investment_before_fixing.lp", my_om=om)
+        om.solve()
+        om.fix_investments()
+        om.solve()
+        self.compare_lp_files("investment_after_fixing.lp", my_om=om)

tests/lp_files/investment_after_fixing.lp

@@ -0,0 +1,81 @@
+\* Source Pyomo model name=Model *\
+
+min 
+objective:
++2000.0 ONE_VAR_CONSTANT
++50 flow(powerplant_gas_electricity_0_0)
++50 flow(powerplant_gas_electricity_0_1)
++50 flow(powerplant_gas_electricity_0_2)
+
+s.t.
+
+c_e_BusBlock_balance(gas_0_0)_:
++1 flow(gas_source_gas_0_0)
+-1 flow(gas_powerplant_gas_0_0)
+= 0
+
+c_e_BusBlock_balance(gas_0_1)_:
++1 flow(gas_source_gas_0_1)
+-1 flow(gas_powerplant_gas_0_1)
+= 0
+
+c_e_BusBlock_balance(gas_0_2)_:
++1 flow(gas_source_gas_0_2)
+-1 flow(gas_powerplant_gas_0_2)
+= 0
+
+c_e_BusBlock_balance(electricity_0_0)_:
++1 flow(powerplant_gas_electricity_0_0)
+= 80.0
+
+c_e_BusBlock_balance(electricity_0_1)_:
++1 flow(powerplant_gas_electricity_0_1)
+= 90.0
+
+c_e_BusBlock_balance(electricity_0_2)_:
++1 flow(powerplant_gas_electricity_0_2)
+= 100.0
+
+c_e_ConverterBlock_relation(powerplant_gas_gas_electricity_0_0)_:
+-1 flow(powerplant_gas_electricity_0_0)
++0.58 flow(gas_powerplant_gas_0_0)
+= 0
+
+c_e_ConverterBlock_relation(powerplant_gas_gas_electricity_0_1)_:
+-1 flow(powerplant_gas_electricity_0_1)
++0.58 flow(gas_powerplant_gas_0_1)
+= 0
+
+c_e_ConverterBlock_relation(powerplant_gas_gas_electricity_0_2)_:
+-1 flow(powerplant_gas_electricity_0_2)
++0.58 flow(gas_powerplant_gas_0_2)
+= 0
+
+c_e_InvestmentFlowBlock_total_rule(powerplant_gas_electricity_0)_:
++0 ONE_VAR_CONSTANT
+= 0.0
+
+c_u_InvestmentFlowBlock_max(powerplant_gas_electricity_0_0)_:
++1 flow(powerplant_gas_electricity_0_0)
+<= 100.0
+
+c_u_InvestmentFlowBlock_max(powerplant_gas_electricity_0_1)_:
++1 flow(powerplant_gas_electricity_0_1)
+<= 100.0
+
+c_u_InvestmentFlowBlock_max(powerplant_gas_electricity_0_2)_:
++1 flow(powerplant_gas_electricity_0_2)
+<= 100.0
+
+bounds
+   1 <= ONE_VAR_CONSTANT <= 1
+   0 <= flow(powerplant_gas_electricity_0_0) <= +inf
+   0 <= flow(powerplant_gas_electricity_0_1) <= +inf
+   0 <= flow(powerplant_gas_electricity_0_2) <= +inf
+   0 <= flow(gas_source_gas_0_0) <= +inf
+   0 <= flow(gas_powerplant_gas_0_0) <= +inf
+   0 <= flow(gas_source_gas_0_1) <= +inf
+   0 <= flow(gas_powerplant_gas_0_1) <= +inf
+   0 <= flow(gas_source_gas_0_2) <= +inf
+   0 <= flow(gas_powerplant_gas_0_2) <= +inf
+end

tests/lp_files/investment_before_fixing.lp

@@ -0,0 +1,86 @@
+\* Source Pyomo model name=Model *\
+
+min 
+objective:
++20 InvestmentFlowBlock_invest(powerplant_gas_electricity_0)
++50 flow(powerplant_gas_electricity_0_0)
++50 flow(powerplant_gas_electricity_0_1)
++50 flow(powerplant_gas_electricity_0_2)
+
+s.t.
+
+c_e_BusBlock_balance(electricity_0_0)_:
++1 flow(powerplant_gas_electricity_0_0)
+= 80.0
+
+c_e_BusBlock_balance(electricity_0_1)_:
++1 flow(powerplant_gas_electricity_0_1)
+= 90.0
+
+c_e_BusBlock_balance(electricity_0_2)_:
++1 flow(powerplant_gas_electricity_0_2)
+= 100.0
+
+c_e_BusBlock_balance(gas_0_0)_:
++1 flow(gas_source_gas_0_0)
+-1 flow(gas_powerplant_gas_0_0)
+= 0
+
+c_e_BusBlock_balance(gas_0_1)_:
++1 flow(gas_source_gas_0_1)
+-1 flow(gas_powerplant_gas_0_1)
+= 0
+
+c_e_BusBlock_balance(gas_0_2)_:
++1 flow(gas_source_gas_0_2)
+-1 flow(gas_powerplant_gas_0_2)
+= 0
+
+c_e_ConverterBlock_relation(powerplant_gas_gas_electricity_0_0)_:
+-1 flow(powerplant_gas_electricity_0_0)
++0.58 flow(gas_powerplant_gas_0_0)
+= 0
+
+c_e_ConverterBlock_relation(powerplant_gas_gas_electricity_0_1)_:
+-1 flow(powerplant_gas_electricity_0_1)
++0.58 flow(gas_powerplant_gas_0_1)
+= 0
+
+c_e_ConverterBlock_relation(powerplant_gas_gas_electricity_0_2)_:
+-1 flow(powerplant_gas_electricity_0_2)
++0.58 flow(gas_powerplant_gas_0_2)
+= 0
+
+c_e_InvestmentFlowBlock_total_rule(powerplant_gas_electricity_0)_:
+-1 InvestmentFlowBlock_invest(powerplant_gas_electricity_0)
++1 InvestmentFlowBlock_total(powerplant_gas_electricity_0)
+= 0
+
+c_u_InvestmentFlowBlock_max(powerplant_gas_electricity_0_0)_:
++1 flow(powerplant_gas_electricity_0_0)
+-1 InvestmentFlowBlock_total(powerplant_gas_electricity_0)
+<= 0
+
+c_u_InvestmentFlowBlock_max(powerplant_gas_electricity_0_1)_:
++1 flow(powerplant_gas_electricity_0_1)
+-1 InvestmentFlowBlock_total(powerplant_gas_electricity_0)
+<= 0
+
+c_u_InvestmentFlowBlock_max(powerplant_gas_electricity_0_2)_:
++1 flow(powerplant_gas_electricity_0_2)
+-1 InvestmentFlowBlock_total(powerplant_gas_electricity_0)
+<= 0
+
+bounds
+   0 <= InvestmentFlowBlock_invest(powerplant_gas_electricity_0) <= 1000
+   0 <= flow(powerplant_gas_electricity_0_0) <= +inf
+   0 <= flow(powerplant_gas_electricity_0_1) <= +inf
+   0 <= flow(powerplant_gas_electricity_0_2) <= +inf
+   0 <= flow(gas_source_gas_0_0) <= +inf
+   0 <= flow(gas_powerplant_gas_0_0) <= +inf
+   0 <= flow(gas_source_gas_0_1) <= +inf
+   0 <= flow(gas_powerplant_gas_0_1) <= +inf
+   0 <= flow(gas_source_gas_0_2) <= +inf
+   0 <= flow(gas_powerplant_gas_0_2) <= +inf
+   0 <= InvestmentFlowBlock_total(powerplant_gas_electricity_0) <= +inf
+end