Generator Constraints Hours Down Coefficient

Units:h
Mode:Input Only
Multi-band:False
Default Value:0
Validation Rule:Any Value
Key Property:No
Description:Coefficient of number of hours the generating unit has been off

Generator Constraints Hours Down Coefficient is the left-hand side coefficient of the number of hours the facility's units have been off referenced to the beginning of the simulation interval i.e. the numbers of hours since the unit last shut down. For the first interval of the Horizon this is determined by Initial Hours Down.

This coefficient is useful for defining custom constraints similar to Generator Min Down Time or for modelling cooling states by combining this coefficient with Generator Constraints Units Started Coefficient.

For the example in Table 1 the Generator "S1C_GT1" cannot start until Generator "GT1" has been off for four hours.

Table 1: Hours Down Coefficient Example
Membership Property Value Units Band
Constraint "EQ7" Sense <= - 1
Constraint "EQ7" RHS 0 - 1
Constraint "EQ7" Generators "S1C_GT1" Units Started Coefficient 1 - 1
Constraint "EQ7" Generators "GT1" Hours Down Coefficient -0.25 - 1


This coefficient can be applied to single-unit or multi-unit facilities. In the latter case, Hours Down Coefficient is the number of hours the whole multi-unit facility has been shut down.