Update the notation of new items in models.py

message_ix/model/MESSAGE/model_core.gms

@@ -145,7 +145,7 @@ Variables
 * =========================================================================== ======================================================================================================
 *
 * .. warning::
-*    Please be aware that transitioning from one period length to another for consecutive periods may result in false values of :math:`\text{PRICE_EMISSION}`. 
+*    Please be aware that transitioning from one period length to another for consecutive periods may result in false values of :math:`\text{PRICE_EMISSION}`.
 *    Please see `this issue <https://github.com/iiasa/message_ix/issues/723>`_ for further information. We are currently working on a fix.
 ***
 
@@ -426,7 +426,7 @@ COST_ACCOUNTING_NODAL(node, year)..
     + SUM(relation$( relation_cost(relation,node,year) ),
         relation_cost(relation,node,year) * REL(relation,node,year) )
 * cost terms associated with linear relations at the sub-annual time slice level
-    + SUM((relation,time)$( relation_cost(relation,node,year) AND
+    + SUM((relation,time)$( relation_cost_time(relation,node,year,time) AND
           (map_relation_time(relation,node,year,time) OR map_relation_year(relation,node,year,time) ) ),
         relation_cost_time(relation,node,year,time) * REL_TIME(relation,node,year,time ) )
 * implementation of slack variables for constraints to aid in debugging

message_ix/models.py

@@ -374,6 +374,8 @@ def initialize(cls, scenario):
 _set("cat_tec", "type_tec t")
 _set("cat_year", "type_year y")
 _set("is_capacity_factor", "nl t yv ya h")
+_set("is_relation_lower_time", "r nr yr h")
+_set("is_relation_upper_time", "r nr yr h")
 _set("level_renewable", "l")
 _set("level_resource", "l")
 _set("level_stocks", "l")
@@ -469,11 +471,15 @@ def initialize(cls, scenario):
 par("ref_new_capacity", "nl t yv")
 par("ref_relation", "r nr yr")
 par("relation_activity", "r nr yr nl t ya m")
+par("relation_activity_time", "r nr yr nl t ya m h")
 par("relation_cost", "r nr yr")
+par("relation_cost_time", "r nr yr h")
 par("relation_lower", "r nr yr")
+par("relation_lower_time", "r nr yr h")
 par("relation_new_capacity", "r nr yr t")
 par("relation_total_capacity", "r nr yr t")
 par("relation_upper", "r nr yr")
+par("relation_upper_time", "r nr yr h")
 par("reliability_factor", "n t ya c l h q")
 par("renewable_capacity_factor", "n c g l y")
 par("renewable_potential", "n c g l y")
@@ -568,6 +574,11 @@ def initialize(cls, scenario):
     "r nr yr",
     "Auxiliary variable for left-hand side of user-defined relations",
 )
+var(
+    "REL_TIME",
+    "r nr yr",
+    "Time-dependent auxiliary variable for left-hand side of user-defined relations",
+)
 var(
     "REN",
     "n t c g y h",
@@ -832,6 +843,25 @@ def initialize(cls, scenario):
     "",
     "Auxiliary equation to simplify the implementation of relations",
 )
+equ(
+    "RELATION_EQUIVALENCE_TIME",
+    "", "time dependent auxiliary equation to simplify the implementation of relations",
+    )
+equ(
+    "RELATION_EQUIVALENCE_YEAR",
+    "",
+    "time dependent auxiliary equation to simplify the implementation of relations at"
+    " the year level",
+    )
+equ(
+    "RELATION_CONSTRAINT_UP_TIME",
+    "",
+    "time dependentupper bound of relations (linear constraints)",
+    )
+equ(
+    "RELATION_CONSTRAINT_LO_TIME",
+    "",
+    "time dependent lower bound of relations (linear constraints)")
 equ(
     "RENEWABLES_CAPACITY_REQUIREMENT",
     "",