OnDemand provides electric utilities with fully automated, direct-control Demand Response. Accurate prediction and integration with SCADA enable it to reliably and accurately control load to meet electric utility energy targets.
The primary objective of OnDemand is to meet the utilities overall energy targets, while at the same time ensuring any instantaneous regional limits within the utilities network are never exceeded. This is achieved by predicting upcoming demand and then directly controlling loads as required to avoid target violations.
Effective and dependable Demand Response requires accurate load prediction. OnDemand utilises sophisticated prediction algorithms to determine the future load profile. The prediction process uses a combination of historical and current load data, including season, day and time, plus relevant environmental conditions. Prediction capabilities for each point of delivery into the network include:
- Average load for the current interval
- Average load for the next interval
- Maximum daily instantaneous load
- Maximum daily instantaneous time
Predicted demand profile for the current 24 hours is maintained for every separate load. Integration with SCADA means SCADA alarm and display facilities can be used to report the maximum predicted load and the time of its occurrence for each of these loads.
OnDemand maintains a model of the load currently available to be shed or restored, for each controllable load in the system. This comprehensive and accurate picture of load enables OnDemand to satisfy both energy and instantaneous demand connection point targets, plus guaranteed on and off times, priorities and load cycling requirements for each of the many controllable loads in the system. Load modelling greatly improves load management accuracy and increases overall network stability.
Managing delivery into the network
OnDemand separately manages each point where the utility network connects to generation and/or transmission networks. It manages controllable load to meet both energy targets and instantaneous equipment loading constraints at these connections. Energy targets are expressed as average demand over a demand interval, commonly 30 minutes.
OnDemand can also ensure that instantaneous demand constraint limits are met for sub-regions within each delivery point area. Multiple sub-regions are supported for every delivery point.
Simplify management of large systems
A load ‘channel’ is a logical grouping of many individual loads into a single load management entity. For example, hundreds of individual domestic hot water cylinders are commonly grouped into a single load management ‘channel’, greatly simplifying management of the network. Each load channel is separately prioritised, controlled and managed.
Channel features include:
- Definable priority levels
- Definable time constraints
- Definable load patterns
- Definable plant delays
- Manual or automatic control
- Definable guaranteed ‘on times’
OnDemand ensures load curtailment is appropriately shared between channels, while also minimising channel switching operations.
All OnDemand decisions and calculations can be recorded in an audit file. This standard text file can be archived and viewed as required. OnDemand can also add messages into the standard SCADA event system. This is restricted to important system information and operational advice, avoiding overload of the SCADA event system.
- Improve network stability
- Defer network investment
- Protect network equipment
- Meet contractual energy targets
- Maximise electricity sales without risk
- Improve quality of supply
- Coordinated, fast emergency load shedding enhances system security
Advantages of OnDemand
- Sophisticated forecasting improves system management, even where automated control is not possible
- Automated direct control increases the accuracy and benefits of demand response
- 24x7 automated DR lowers investment and operational costs
- Extensive auditing and logging facilities provide secure, accountable operation
- Full integration into SCADA platforms enables real-time closed-loop load control
- Integration with SCADA delivers DR without adding another user interface into the control room.
- OnDemand load modeling and channel management both ensure equitable DR to match both commercial and quality of service obligations
- Field proven by multiple utilites in 24x7x365 operation since the 1990’s, OnDemand is the ultimate effective and low-risk solution