About alternative demand

The Alternative Demand object provides the ability to define an alternative set of demand values for a Network without altering the network itself.

Customer Point, Land Use, and Node demand information defined in the Alternative Demand object, can then be used to override the demands in a network when carrying out a simulation. This functionality allows different demand scenarios to be modelled without the need to create a different network for each demand set.

Using alternative demands

The Alternative Demand item is intended for use in modelling different demand scenarios in situations where the physical network has not changed. Alternative Demands are used to model changes to existing network demand. These changes may be changes in magnitude, or changes in type of demand.

Alternative Demand values can be used instead of network Customer Point, Land Use, and Node demand values when running a simulation. The Alternative Demand must contain a record for each Customer Point and Node (for Node Demand and Land Use Demand) that exists in the network to which it is to be applied. Customer Point and Node data from a network can be copied to an Alternative Demand at any time by initialising the Alternative Demand from the Network.

Any alternative demand information relating to Customer Points or Nodes that do not exist in the network will be ignored. Significant changes to network demand, involving the addition of new areas or Customer Points, should be modelled using a new network.

Data from an Alternative Demand item can also be copied to a network. See the Copying Alternative Demand to the Network topic for further details.

Editing alternative demands

Alternative Demand data can be edited by Associating Alternative Demand with a Network and then editing alternative demand information for the objects in the associated network. Alternatively, Alternative Demand can be edited independently of the network in the Alternative Demand Grid.

Alternative Demand data can be updated from CSV Files or by using the Open Data Import Centre.

Using alternative demands in a simulation

To use an Alternative Demand to override Network Demands, include the Alternative Demand in the Schedule Hydraulic Run dialog when Creating and Scheduling a Run.