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Head Loss
This category depends on the Unit Power Table method and contains methods for modeling additional head loss that occurs. This head loss may come from the configuration of the penstocks for bringing water to the turbines.
* None
In this method, there is no additional head loss to be used in the power calculation. In terms of penstock head loss, this method should be selected if the penstocks for the units are independent and the penstock losses are typically incorporated in the power data. Thus the power data is specified in terms of operating head.
* Shared Penstock Head Loss method
In this method, there is additional head loss that results because units share a common penstock. The operating head losses in the penstock depend on the total turbine release and are shared for all units. The net head is calculated by subtracting penstock losses from the operating head. The unit data and power must be specified in terms of unit Net Heads instead of Operating Head.
Slots Specific to This Method
 Shared Penstock Head Loss Table
Type: TableSlot
Units: Flow vs Length
Description: This table shows head losses in a shared penstock as a function of total turbine release.
Information: The table has two columns: Turbine Release and Shared Penstock Loss.
I/O: Required Input
Method Details 
In simulation, when either the Unit Power Table or Unit Power Table Release method is called, it has an estimate of operating head calculated as average PE minus average tailwater elevation. Within these methods, if the Shared Penstock Head Loss method is selected, the code will look up an estimate of total Turbine Release and compute the additional head loss and subtract it from the existing operating head before use in any other equation. An iterative solution is needed if Turbine Release is not known; that is, if this method is called from the Unit Power Table Release method.
Revised: 08/02/2021