Add MeterID and ParentResourceUseID to ResourceUse

BuildingSync.xsd

@@ -4046,6 +4046,19 @@
           </xs:sequence>
         </xs:complexType>
       </xs:element>
+      <xs:element name="MeterID" type="xs:string" minOccurs="0">
+        <xs:annotation>
+          <xs:documentation>ID of the associated meter as seen by the facility manager</xs:documentation>
+        </xs:annotation>
+      </xs:element>
+      <xs:element name="ParentResourceUseID" minOccurs="0">
+        <xs:annotation>
+          <xs:documentation>If this ResourceUse is intended to represent a submetered end use ('Total Lighting', 'Heating', 'Plug load', etc.), this ResourceUse should link to a parent ResourceUse that this would 'roll up to'.</xs:documentation>
+        </xs:annotation>
+        <xs:complexType>
+          <xs:attribute name="IDref" type="xs:IDREF" use="required"/>
+        </xs:complexType>
+      </xs:element>
       <xs:element ref="auc:UserDefinedFields" minOccurs="0"/>
     </xs:sequence>
     <xs:attribute name="ID" type="xs:ID" use="required"/>

proposals/2020/Resource Use Submetering.md

@@ -0,0 +1,34 @@
+# Resource Use Submetering
+
+## Overview
+
+This proposal is to modify `auc:ResourceUse` to allow modeling of submeters.
+
+## Justification
+
+SPC 211 Standard for Commercial Building Energy Audits section 6.2.2.1.d states the following regarding historical utility data.
+> A description of the submetering installed in the building (if present), including a listing of the systems metered, the frequency of data recording, and a description of the data acquisition system (fixed, portable, or integrated with the BAS), shall be provided.
+
+## Implementation
+
+### Option 1
+Use ResourceUses to model submetering by adding the elements `auc:MeterID` and `auc:ParentResourceUseID`. `auc:MeterID` should contain the ID of the meter as seen by the facility manager. `auc:ParentResourceUseID` links to another `auc:ResourceUse` to signify that it's a submeter of the parent resource use.
+
+#### Pros
+- simple, no breaking changes
+
+#### Cons
+- Not great data modeling
+
+### Option 2
+Implement a new metering modeling system. This would incur a breaking change most likely, and the implementation is currently uncertain.
+
+#### Pros
+- better data modeling
+
+#### Cons
+- breaking change
+
+## Decision
+
+We've decided to go with Option 1 for now, and push the refactoring of meter modeling to BuildingSync v3