3.5 Unavailability Deduction
3.5.1 Unavailability Deductions will be calculated with reference to the following formula. The calculation is carried out on a monthly basis according to all the Unavailability events during that month.
3.5.2 The Unavailability Deduction shall be calculated as follows:
UDn | = | ARn x WFn x DPn x UUn x RDmx-3 |
where: | ||
UDn | = | the Unavailability Deduction for Arean |
ARn | = | the Area Rate for Arean |
WFn | = | the Weighting Factor for Arean |
DPn | = | the number of Deduction Periods for Arean |
UUn | = | Unavailable but Used. This is equal to one if the Area is Unavailable and not used and is equal to 0.50 if the Area is Unavailable but Used |
RDmx-3 | = | Repetition Deduction. This is equal to 1.5 if the same Availability Criteria has failed more than four times in a month for an Area, and is equal to 2 if the same Unavailability Criterion has failed more than eight times during the same month. In all other instances it is equal to one. |
3.5.3 Area Rate
The Area Rate for each year will be calculated in accordance with the following:
|
| |||
where: | |||
APy | = | the Annual Unitary Charge for the relevant year indexed in accordance with paragraph 2.7 | |
TAW | = |
| |
Where: | |||
WFn | the Weighting Factor for Area (n) | ||
DPOn | the number of Deduction Periods for Area (n) | ||
