An overview of the SAREF4ENER ontology is provided in Figure 1, where rectangles containing an orange circle are used to denote classes created in SAREF4ENER, while rectangles containing a faded orange circle denote classes reused from other ontologies, such as SAREF. For all the entities described in the present document, it is indicated whether they are defined in the SAREF4ENER extension or elsewhere by the prefix included before their identifier, i.e. if the element is defined in SAREF4ENER the prefix is s4ener:, while if the element is reused from another ontology it is indicated in the Namespace Declarations section.
Arrows with white triangles on top represent the rdfs:subClassOf relation between two classes. The origin of the arrow is the class to be declared as subclass of the class at the destination of the arrow.
Directed arrows are used to represent properties between classes.
Rectangles that contain a list of values between square brackets denote an enumeration of individuals.
Note that Figure 1 aims at showing a global overview of the main classes of SAREF4ENER and their mutual relations. More details on the different parts of Figure 1 are provided below.
Figure 2 shows the hierarchy of classes and properties defined in SAREF4ENER.
Orange circles represent classes of SAREF4ENER, while faded orange circles represent classes that are reused from other ontologies. Object properties - which are properties between two classes - are denoted by blue rectangles, while datatype properties - which are properties between a class and a data type, such as xsd:string or xsd:dateTime - are denoted by green rectangles. Faded blue and green rectangles denote object properties and datatype properties that are reused from other ontologies.
A s4ener:Device is a subclass of a saref:Device, i.e. it inherits the properties of the more general saref:Device and extends it with additional properties that are specific for SAREF4ENER. The s4ener:Device class is shown in Figure 3.
This clause presents the classes of interest for smart energy management. These classes are used to schedule devices in certain modes and preferred times using power profiles to optimize energy efficiency and accommodate the customer's preferences (i.e. use case 2). These classes are s4ener:PowerProfile, s4ener:Alternative, s4ener:PowerSequence and s4ener:Slot, which are shown in Figure 4.
A s4ener:PowerProfile is a subclass of a saref:Profile, i.e. it inherits the properties of the more general saref:Profile extending it with additional properties that are specific for SAREF4ENER. The s4ener:PowerProfile is used by a s4ener:Device to expose the power sequences that are potentially relevant for the CEM. A s4ener:Device can expose a s4ener:PowerProfile, which consists of one or more alternative plans (s4ener:AlternativesGroup class). A s4ener:AlternativesGroup consists of one or more power sequences (s4ener:PowerSequence class), and a s4ener:PowerSequence consists of one or more slots (s4ener:Slot class). Inversely, a s4ener:Slot belongs to only and exactly one s4ener:PowerSequence, which, in turn, belongs to only and exactly one s4ener:AlternativesGroup, which, in turn, belongs to only and exactly one s4ener:PowerProfile. A s4ener:PowerProfile belongs to only and exactly one s4ener:Device.
The s4ener:AlternativesGroup consists of one or more power sequences (s4ener:PowerSequence class) and, inversely, a s4ener:PowerSequence belongs to only and exactly one s4ener:AlternativesGroup. Figure 5 shows the details of the s4ener:PowerSequence class.
The s4ener:PowerSequence consists of one or more slots (s4ener:Slot class) and, inversely, a s4ener:Slot belongs to only and exactly one s4ener:PowerSequence. Figure 6 shows the details of the s4ener:Slot class.
This clause presents the part of SAREF4ENER that defines how to model events used in, for example, a direct load management and power curtailing scenarios (i.e. use case 4). The classes of interest are s4ener:LoadControlEventData, s4ener:LoadControlEventAction, s4ener:LoadControlStateData and s4ener:LoadControlState, as shown in Figure 7.
The s4ener: LoadControlEventData class is used to represent overload warning severity level and related load control commands to a device. It is characterized by an event ID and a timestamp that represents the time the event information instance was created or received, and the time period that denotes the period of validity of the event. For example, 5 minutes ago an event was received which says that it shall take effect tomorrow from 14:00 to 15:30. In this event the timestamp is "5 minutes ago" and time period is "tomorrow from 14:00 to 15:30".
The s4ener:LoadControlEventAction class expresses the type of actions to be performed as a consequence of a load control event. A s4ener:LoadControlEventAction can be of type "consume" or "produce" to denote consumption or production of energy or power. Values for both consume and produce actions can be s4ener:emergency, s4ener:increase, s4ener:normal, s4ener:pause, s4ener:reduce, s4ener:resume.
The s4ener: LoadControlStateData class expresses the data about the state of an event and is characterized by the same event ID used in the s4ener:LoadControlEventData class, as well as a timestamp, and it is associated to the class s4ener:LoadControlState, which can be of type "consume" or "produce" - analogously to a load control event action – and expresses the possible states of a load control event. Values for both consume and produce load control states can be s4ener:eventAccepted, s4ener:eventStarted, s4ener:eventStopped, s4ener:eventRejected, s4ener:eventCancelled, or s4ener:eventError.
