Add lower bound for transport flows

Author: gnawin

src/constraints/capacity.jl

@@ -352,6 +352,26 @@ function add_capacity_constraints!(connection, model, expressions, constraints,
             ],
         )
     end
+
+    cons_name = Symbol("min_output_flows_limit_for_transport_flows_without_unit_commitment")
+    table_name = :min_outgoing_flow_for_transport_flows_without_unit_commitment
+
+    # - Maximum input flows limit
+    attach_constraint!(
+        model,
+        constraints[table_name],
+        cons_name,
+        [
+            @constraint(
+                model,
+                outgoing_flow ≥ 0,
+                base_name = "$cons_name[$(row.asset),$(row.year),$(row.rep_period),$(row.time_block_start):$(row.time_block_end)]"
+            ) for (row, outgoing_flow) in
+            zip(constraints[table_name].indices, constraints[table_name].expressions[:outgoing])
+        ],
+    )
+
+    return
 end
 
 # The below two functions are very similar

src/constraints/create.jl

@@ -16,6 +16,7 @@ function compute_constraints_indices(connection)
             :capacity_outgoing_simple_method,
             :capacity_outgoing_simple_method_non_investable_storage_with_binary,
             :capacity_outgoing_simple_method_investable_storage_with_binary,
+            :min_outgoing_flow_for_transport_flows_without_unit_commitment,
             :limit_units_on_compact_method,
             :limit_units_on_simple_method,
             :min_output_flow_with_unit_commitment,

src/model-preparation.jl

@@ -531,6 +531,7 @@ function add_expressions_to_constraints!(connection, variables, constraints)
         :capacity_outgoing_simple_method,
         :capacity_outgoing_simple_method_non_investable_storage_with_binary,
         :capacity_outgoing_simple_method_investable_storage_with_binary,
+        :min_outgoing_flow_for_transport_flows_without_unit_commitment,
     )
         @timeit to "add_expression_terms_rep_period_constraints! for $table_name" add_expression_terms_rep_period_constraints!(
             connection,

src/sql/create-constraints.sql

@@ -195,6 +195,38 @@ where
 drop sequence id
 ;
 
+create sequence id start 1
+;
+
+create table cons_min_outgoing_flow_for_transport_flows_without_unit_commitment as
+
+with transport_flow_info as (
+    select
+    asset.asset,
+    coalesce(
+        (select bool_or(flow.is_transport)
+         from flow
+         where flow.from_asset = asset.asset),
+         false
+    ) as outgoing_flows_have_transport_flows,
+    from asset
+)
+select
+    nextval('id') as id,
+    t_high.*
+from
+    t_highest_out_flows as t_high
+    left join asset on t_high.asset = asset.asset
+    left join transport_flow_info on t_high.asset = transport_flow_info.asset
+where
+    asset.type in ('producer', 'storage', 'conversion')
+    and transport_flow_info.outgoing_flows_have_transport_flows
+    and not asset.unit_commitment
+;
+
+drop sequence id
+;
+
 create table cons_limit_units_on_compact_method as
 select
     *