This article will teach you all about the last step in setting up your case: Strategy.
In the Strategy Menu, you can fill in high-level information for the strategy of a project. The details you can define depends on your needs as well as which of our tools you are using (O&M Design strategy found here). Below you will find more information on how to complete this final step before you can run your simulation.
This article includes the following headings:
- Strategy in Construction Design
- Installation package dependencies
- Grid start date
- Case timezone
- General
- Cable installation strategy
- Learning curve
- Technical maintenance parameters
Strategy in Construction Design
In the strategy of a Construction Design case you can define:
- the installation order and start criteria of the different packages in the case
- define a global learning curve for all installation process cycles
- bulk edit grid start date for all WTGs
- case timezone
- cable installation strategy if there are cables in the case
- emergency response limit for technician transfers
- the minimum working time on completion, commissioning, snagging and post commissioning tasks
This is explained in the text below.
You find the strategy settings in a case here:
- Go to Build → Strategy.
- Fill in the information in the following input boxes:
Installation package dependencies
Note: The order of installation packages is required before running a simulation. Changing the order of installation packages is done by dragging and dropping the packages into the desired order.
The order of the packages defines in what order packages are installed. If the assets in packages are related (added with the "add related" functionality) you can define the criteria for starting the installation of the next package on a location. If the assets are not related the simulation only looks are the date or when all the assets in the previous package have been installed.
From the drop-down menu on each package the following start criteria can be chosen:
| Input label | Mandatory | Description |
|---|---|---|
| Continuous | - | If the previous package in the list was added using "add related" the installation of the asset will start as soon as the asset from the previous asset has been installed (e.g. the foundation on the location is installed then the wind turbine can be loaded out and installed). NOTE: if the assets were not added using "add related" this setting will work like the Completed setting. |
| Completed | - | All the assets in the previous package have to be installed before loadout and installation can begin. |
| Date | - | The installation of the package can start at a specific date (Mandatory for the first package). NOTE: if the package was added using add related the installation can start at the set date AND after the asset from the previous package on that position has been installed. |
| Delay | - | Same as Continuous, but with an additional delay from the previous asset is installed until the loadout can start. |
An example is: the grouting connections must be placed after jacket/transition piece installation and before the whole wind turbine package, with a continuous dependency. The timestamp for when the grouting is completed is when the vessel is done with the task, and hence before the hardening is complete.
Note for component transfers: The delay setting does not work on the first Component transfer, as the Component transfer is not connected to any installation package. If there are two sets of component transfers, like a three-port setup where one component is transferred from port A to port B, then from port B to port C, then the delay should be applied to the second component and the delay would be shown on the second set of transfers.
In the following example, the mooring anchor will be installed 2020-07-06. The first jacket will be installed after the installation of the first piles. Thereafter, the wind turbines will be installed which is at the time of completed installation of all the jackets. The installation of the inter-array cables will start at the 2020-08-03.
Grid start date
Grid start date can be set up for all turbines in the strategy section or individually from the Asset section. Click on Bulk edit all WTG Grid start dates...
Then select the date from the calendar and apply.
Case timezone
In the Case timezone, you set the time zone for the wind farm, so the weather file(s) used in the simulation reflects the actual time of day.
General
Emergency response limit
The emergency response limit sets how far a transport logistic can travel from an asset while work is being conducted. It is defined in minutes: set the maximum amount of time a vessel requires to get back to a technician team in an emergency.
For example, if the emergency response time limit is 30 minutes and a technician team is dropped off at asset A, the logistic that dropped off the technician team can only access assets within a 30-minute radius of asset A.
We recommended that you set something realistic (30–60 minutes) even if your site does not legally require an emergency response limit, as it can affect your simulation results.
The effect of the emergency response limit
The effect of different values for the emergency response limit is impossible to predict. Generally, the lower the limit, the fewer tasks can be carried out simultaneously, reducing up time. Inversely—and still generally—the higher the limit, the more tasks can be carried out simultaneously, increasing up time. However, as this is a general rule, there are scenarios where a lower limit can reduce the travel time of the logistic, allowing more maintenance to be conducted in a smaller area, resulting in increased up time.
We advise you to run comparisons with slightly different values for the emergency response limit if you are interested in seeing the effect it has on your case. If the effect is minor or not noticeable, you can leave the HSE in the 30–60-minute recommended range.
Minimum working length
This setting is there to ensure offshore trips are only done if some minimum amount of work can be done. If a task has a longer remaining repair time than the minimum working length you will only send people offshore if they can do at least X hours of work on the asset. This excludes the necessary travel and transfer time to and back from the asset.
Cable installation strategy
You can specify the type of vessels involved in the cable installation process. At least one of the strategies need to be chosen when installing cables.
| Input label | Mandatory | Description |
|---|---|---|
| No mobilisation of foundations | - | The cable end installation (e.g. cable pull-in) is done with personnel and equipment transferred from the cable laying vessel. |
| Mobilise foundation with SOV | - | The SOV will act as a construction support vessel (CSV) transporting technicians and the cable pull-in equipment to each foundation in time for when the cable installation vessel is ready for the pull in. The SOV will distribute pull in equipment in containers in parallel with other tasks to keep the cable installation vessel working. The containers will be picked up after cable end installations on a location is done. Cable pull in container transfer time can be defined under Activity Durations for an SOV and the number of containers the SOV carries is defined on the SOV member. The technicians live on the SOV. |
| Mobilise foundation with CTV | - | The CTV will act as a construction support vessel (CSV) but is in this case only used for transportation of technicians to the cable pull-in locations in time to not delay the cable installation vessel. The technicians are picked up from the cable installation vessel, and the CTV will come from an onshore port. |
Learning curve
You are able to define a global learning curve in the strategy tab that is applied to all loadout and installation tasks; you can also set a learning curve on the cycle steps on the respective installation vessel.
If you use both the global learning curve, and the individual learning curve per cycle, it's the latter which will be used.
What is the learning curve?
Learning curves express that experience is gathered when performing operations and this results in a change in task duration according to the learning curve. The learning curve in Shoreline works, so it counts the number of operations and multiplies the input duration of the cycle with the percentage of activity time you added.
In the below example, the first operation (e.g. Installation) will take 50% longer than expected. After that, the second operations for both processes will take 25% more time. The third time this cycle is performed, it will take the estimated time you added in the 'cycle' set up.
Note: The lowest % should always be 100%. If you do not add 100%, the duration will gradually decrease, causing inaccurate data. In the example below, you can see that as of the 3 load-out or installation cycle, the learning curve is 100%; therefore all cycles that follow will also do the task in the estimated time. If you had not added 100%, each cycle would gradually decrease.
If you hover your mouse over the 'i' icon we will have an in-app explanation to help guide you:
The table where you define the learning increments is applied to all these process steps:
- Load out (applied to the installation vessel cycle for load-out)
- Pile drive (applied to the installation vessel cycle for pile drive)
- Pile drill (applied to the installation vessel cycle for pile drill)
- Foundation Installation (applied to the installation vessel cycle for foundation installation)
- Wind turbine Installation (applied to the installation vessel cycle for wind turbine installation)
- Substation Installation (applied to the installation vessel cycle for substation)
- Cable installation (applied to the task input for cable end pull in on the respective cable)
The following vessels are considered installation vessels:
- Heavy lift vessel
- Cable installation vessel
- Towing vessel
- Anchor handling vessel
- Feeder vessel
- Component transfer vessel
Multiple vessels
If you have multiple installation vessels on a case, the global learning curve PR cycles will apply to all vessels in the same category. Example: if there are two HLVs in the case on the same configuration (both HLVs are in one HLV configuration), then the first loadout on the first vessel will use PR cycle 1, while the first loadout for the second vessel will use PR cycle 2.
Technical maintenance parameters
Loadout and Installation tasks: Adjusts upwards all loadout and installation tasks durations, as well as decreasing cable lay and burial speeds, by the specified percent for all installation vessels.
Technical maintenance parameters marine operation tasks: Adjusts upwards all other tasks durations, as well as decreasing transit and positioning speeds, by the specified percent for all installation vessels.
