Production-based availability is a measure of how much of the potential production is actually produced. Defined here:
PBA [%] = Actual production [MWh] / Potential production [MWh]
These terms explained
- Potential production is the amount of energy an asset can produce if it was always operational (never fails or shuts down). Found by calculating energy production using the power curve of the asset and the wind speed at hub height.
- Actual production is the amount of energy an asset produces when operational. Found by calculating energy production using the power curve of the asset and the wind speed at hub height.
- Lost production is the energy not produced when an asset is non-operational but would be produced if it was operational. Calculated as the difference between potential production and lost production.
PS! If failures and scheduled maintenance occur in periods of low wind speeds the PBA loss is minimized because the lost production in low wind periods is less.
An example for one asset during one month:
- Lost production: 85 MWh
- Actual production: 4,165 MWh
This gives a PBA of:
Possible production = 4,165 MWh + 85 MWh = 4,250 MWh
PBA = 4,165 MWh / 4,250 MWh = 0.98 = 98%
The PBA Raw data information is found further down.
| Category | Description |
|---|---|
| Lost Production (PBA Root Causes) | This is the total lost production measured in the simulation for reference (MWh). |
| Schedule service work WTG | This is the lost production during scheduled maintenance work on the asset. It only counts the lost production between a team start work to the team stop work (does not include waiting for pick-up) |
| Major lead time | This is the lost production from the creation of a jack-up work order for major component replacement and the actual start of the lifting work with the heavy-lift vessel or until it’s necessary to wait for weather after the heavy lift vessel arrives at the asset, it includes e.g.:
It also represents the total for the subcategories below: waiting to be scheduled for the support vessel, waiting to be scheduled for HLV, no available support vessel, no available HLV |
| Major lead time - Waiting to be scheduled for the support vessel | This is set when work is stopped and waiting for the next scheduling on the CTV. This limiting factor is used when we are in one of the support vessel stages of the task, and the work is stopped at the turbine; then this limiting factor is the one used until the next time we try to schedule the vessel. It is also used when work is completed and the next stage is a support vessel stage The reason the work stops is because the vessel needs to be back at port before work shift ends, or before it becomes bad weather. |
| Major lead time - Waiting to be scheduled for HLV | This is set when work is stopped and waiting for the next scheduling on the HLV. |
| Major lead time - No available support vessel | This is set when trying to schedule but could not. |
| Major lead time - No available HLV | This is set when trying to schedule but could not. |
| Major weather delay | This is the lost production waiting for weather windows to perform inspection, preparation, replacement and finalization work either with the support CTV or the HLV. |
| Major work WTG | This is the lost production when the HLV is actually performing the replacement task and when the inspection, preparation, and finalization work is done. |
| Minor work WTG | This is the lost production for repair tasks requiring crew transfer, e.g. technicians transferred with a CTV, SOV, car or helicopter from when technicians access the asset to finish work (does not include the time waiting for pickup). |
| Minor weather delay | This is the lost production when waiting for a weather window to repair a minor component failure that requires transport from a CTV, SOV, car or helicopter. |
| Minor response time | This is the lost production between the creation of the work order for minor component failure and the actual start of the work or until it's necessary to wait for weather, it includes e.g.:
It also represents the total for the subcategories below: no room on asset, no available vessel, no available personnel, emergency response limit, no dropoff and pickup combination, waiting to be scheduled |
| Minor response time - No room on asset | No team of technicians can perform work on the WTG as the space is already full |
| Minor response time - No available vessel | This is set when trying to schedule the vessel but could not |
| Minor response time - No available personnel | This is set when trying to schedule personnel but could not |
| Minor response time - Emergency response limit | Restriction to carry the scheduled tasks on assets outside this limit |
| Minor response time - No dropoff and pickup combination | Unable to find a way of doing the drop-offs or pickups, with the combination of tech/vessel availability, the current weather windows and the other tasks planned |
| Minor response time - Waiting to be scheduled | A vessel is set in the step when work is stopped and we are waiting for the next scheduling. Example: if scheduling for the day starts at 06:00, and worked on until 18:00, then the next 12 hours will be considered "Waiting to be scheduled". |
| Floating work WTG | This is the lost production during repair work in the port with cranes or the disconnection or hook-up durations offshore for a floating component failure |
| Floating weather delay | This is the lost production for waiting for a weather window to perform operations on a floating asset in the port with cranes or the towing operations. |
| Floating response time | This is the lost production between the creation of the work order for a floating component failure and the actual start of the work |
| Floating towing time | This is the lost production during a towing operation |
| External Schedule service work WTG | This is the lost production during scheduled maintenance work on the Substation. It only counts the lost production between a team start work to the team stop work (does not include waiting for pick-up) |
| External Minor work WTG | This is the lost production for repair tasks requiring crew transfer, e.g. technicians transferred with a CTV, SOV, car or helicopter from when technicians access the Substation to finish work (does not include the time waiting for pickup). |
| External Minor weather delay | This is the lost production when waiting for a weather window to repair a minor component failure that requires transport from a CTV, SOV, car or helicopter in the Substation. |
| External Minor response time | This is the lost production between the creation of the work order for minor component failure in the Substation and the actual start of the work or until it's necessary to wait for weather, it includes e.g.:
It also represents the total for the subcategories below: no room on asset, no available vessel, no available personnel, emergency response limit, no dropoff and pickup combination, waiting to be scheduled |
| External Minor response time - No room on asset | No team of technicians can perform work on the Substation as the space is already full |
| External Minor response time - No available vessel | This is set when trying to schedule the vessel to carry work on the Substation but could not |
| External Minor response time - No available personnel | This is set when trying to schedule the personnel teams to carry work on the Substation but could not |
| External Minor response time - Emergency response limit | Restriction to carry the scheduled tasks on the Substation outside this limit |
| External Minor response time - No dropoff and pickup combination | Unable to find a way of doing the drop-offs or pickups on the Substation, with the combination of tech/vessel availability, the current weather windows and the other tasks planned |
| External Minor response time - Waiting to be scheduled | A vessel is set in the step when work is stopped and we are waiting for the next scheduling on the Substation. |
| Root causes total | This is the sum of lost production for all root causes above |
PBA Root cause raw data
| Cell | Description |
|---|---|
| Column A | Wind farm name (if "default", no wind farm name has been added). |
| Column B | Displays the root cause (to be used in accordance with the table above). |
| Column C | Displays the simulation year. |
| Column D | Displays the run number. |
| Column E | Displays the value. Note: The value printed here is either in hours or in percentile (1=100%). |