Utilities

The Utilities page shows the utilities available as part of your reference data, together with their units of measure.

The behavior of this page is controlled by the Utility Management optional feature:

• If the feature is disabled (default), the page is read only.

• If the feature is enabled, you can override system utilities, and also create and share new utilities.

The following image shows available utilities listed in the Utilities page. Here the Utility Management feature is enabled: note that the Catalyst Usage utility has been overridden.

Utilities are special properties. While they have a unit of measure like other properties, utilities cannot be associated with a stream, but are instead associated with process model flows or base loads.

Utilities are used to fuel process units. Utilities include electricity, steam and catalysts. Utilities are often purchased by a plant, or produced in a process unit within the plant. Some utilities, such as catalysts, are always purchased.

Although most process units consume or produce utilities, it is not necessary to connect utility streams to each individual unit. Instead, utilities are passed around through virtual streams that exist across the whole flowsheet. For example, most units require electricity for their operation, and the electricity consumption is contained within the process model associated with the unit. Therefore it is necessary to supply electricity to these units. This can be achieved by either adding electricity as a utility purchase in the Purchases page, or by adding a process unit that generates electricity. If you add a process unit, the electricity generated is then available to all process units without having to physically connect each process unit to the generation unit.

Similarly, many units require steam. Steam may be high or low pressure, which are treated as two different types of utility. A steam generation process unit usually produces steam of both types. Again, the production of this unit extends across the whole flowsheet and is available to any process unit without having to physically connect the process unit to the source of steam. Some units may produce steam during their operation, that is, their process models output steam. This steam is added to the virtual pool and so becomes available to the other process units.

Types of utility

Note: You can add, edit and delete utilities only if the Utility Management feature is enabled.

There are three types of utility:

• System utilities are the utilities included by default with AVEVA Unified Supply Chain. They are denoted by the icon. You cannot delete a system utility, but you can edit it to override its default unit of measure.

• Reference data overrides of system utilities are system utilities you have overridden. They are initially denoted by the icon, and then by the icon after committing. If you delete one of these utilities, it is replaced by the original system utility.

• Reference data utilities are new utilities you have created. They are also denoted by the icon, and by the icon after committing. If you delete one of these utilities, it is completely removed.

  Tip: When you create reference data utilities and overrides of system utilities, you can choose the share where to commit them. Make sure to choose a public share if you want other users to be able to access them.

Add, edit and delete utilities

Note: The following applies only if the Utility Management feature is enabled.

To add a utility:

1. Do either of the following:

   • Click Add Utility in the Utilities group of the Home ribbon tab.

   • Right-click anywhere in the table and choose Add Utility from the context menu.

2. In the Add Utility dialog box, choose the utility you want to add, the default unit of measure and the share where to publish it.

3. Click OK. The utility is added to the list.

To edit a utility:

4. Select the utility you want to edit.

5. Do either of the following:

   • Click Edit Utility in the Utilities group of the Home ribbon tab.

   • Right-click on the selected utility and choose Edit Utility from the context menu.

6. Make your edits in the Edit Utility dialog. Note that you cannot change the value in the Utility field.

7. Click OK. Your changes are applied to the utility.

To delete one or more utilities (not system utilities):

8. Select the utilities you want to delete.

9. Do either of the following:

   • Click Delete Utilities in the Utilities group of the Home ribbon tab.

   • Right-click on the selected utilities and choose Delete Utilities from the context menu.

10. Click Yes in the confirmation dialog.