Generator Rating

Units:	MW
Mode:	Input/Output
Multi-band:	False
Default Value:	0
Validation Rule:	Any Value
Key Property:	No
Description:	Rated capacity of units
Detail:

Generator Rating overrides the Max Capacity.

Rating allows for periodic adjustments to a generator's capacity (e.g. summer and winter rating) without affecting the calculation of the installed capacity and thus allowing for the correct calculation of capacity factor. As with any property in PLEXOS the rating can be dated, patterned, scenario'd and even read from a text file (list of values by period).

Rating most commonly has a pattern, e.g. summer and winter, or peak and off-peak, to which the rating value applies. Once you decide to use the rating property over a certain period of time, sufficient additional rating properties must be specified such that their associated patterns are fully complementary. If you omit a pattern, PLEXOS assumes that the default rating is zero - PLEXOS does not use the max capacity as a default once you start to specify rating properties. For example, suppose that you set a generator's max capacity equal to 250MW and then specify a rating with pattern SUMMER equal to 225 MW. You must also specify a rating with pattern WINTER, otherwise, PLEXOS assumes that the WINTER rating is zero. This requirement applies generally to any set of complementary patterns e.g.:

PEAK / OFF-PEAK
WEEKDAY / WEEKEND
SUMMER / WINTER

Example:

Generator	Property	Value	Units	Timeslice
PEAKER	Units	1	-
PEAKER	Max Capacity	250	MW
PEAKER	Rating	225	MW	SUMMER
PEAKER	Rating	250	MW	WINTER

The main motivation for using the rating properties to change the generation limit rather than the max capacity is that the latter is used to compute kW/year fixed cost charges.

Note that for the output property, rating is the rated capacity with respect to the degradation effect (if defined).