Facility Efficiency Incr

Units: %
Mode: Input Only
Multi-band: True
Default Value: 100
Validation Rule: Any Value
Key Property: No
Description: Primary Process Efficiency at the given [Efficiency Point]
Detail:

Facility Efficiency Incr is used in multi-band pairs with Efficiency Point to define a custom efficiency function for the Primary Process conducted by the Facility overriding the Process Efficiency. The value in band n is the average efficiency between the Efficiency Point n - 1 and n.

Table 1: Efficiency Incr Example
Facility Property Value Units Band
NH3.Plant Max Efficiency Tranches 2 - 1
NH3.Plant Efficiency Point 40 % 1
NH3.Plant Efficiency Point 100 % 2
NH3.Plant Efficiency Incr 3506.25 % 1
NH3.Plant Efficiency Incr 6010.71 % 2


For the example in Table 1, the raw data are shown in Table 2. Here the input and output energy of the process are used to calculate the efficiency at each production level and then the incremental efficiency using the formula:

Efficiency Incrn = 100 × ( Output Energyn - Output Energy(n-1) ) / (Input Energyn - Input Energy(n-1) )

Table 2: Raw Data for Calculation of Efficiency Incr
Input (MWh) Output (kg) Input (MJ) Output (MJ) Efficiency Efficiency Incr
3.5
 19,635
 12,600
 441,787.5
 3,506.25%
 3,506.25%
8.75
 70,125
 31,500
 1,577,812.5
 5,008.93%
 6,010.71%


The number of bands (tranches) used in the simulation is set by the Max Efficiency Tranches setting. If you want your efficiency function used 'verbatim' then set this value equal to the number of bands of input supplied, otherwise if you set the value higher or lower than the number of bands supplied the efficiency function will be recalculated to match that number of bands.

The incremental efficiencies do not need to be monotonic e.g. always increasing or decreasing. By default the function is formulated with integer decision variables and constraints that ensure the efficiency bands are taken up in order. You can control this with the Formulate Non-convex setting.