Time series variability blog

How do different aspects of the input metocean data affect Mermaid results?

There are a range of sources of variability when it comes to putting together a Mermaid analysis, and they can all affect the output statistics to various degrees.  It could be subtle changes such as weather thresholds, task durations or the level of suspendability; or more strategic changes such as vessel and port choice.  But that’s what Mermaid is designed for, for you to be able to tweak and optimise your operation to minimise the weather risk. Read more >

Vattenfall adopts James Fisher’s pioneering marine project optimisation system, Mermaid®.

  • James Fisher Marine Services secures order from one of Europe’s leading energy companies, Vattenfall, for Mermaid®
  • Vattenfall will utilise Mermaid® for the strategic planning of its offshore wind farm operations
  • Mermaid® is a sophisticated marine project optimisation and weather risk mitigation system set to enable huge operational cost-savings

James Fisher Marine Services, part of James Fisher and Sons plc, is proud to announce that Vattenfall, one of Europe’s leading -wind park operators, has ordered a full Mermaid® system license for the strategic planning of its offshore wind farm operations. Read more >

Analysing Wind Farm Foundation Installation – Part 7: Two Vessels – The Division of Labour

In the last post we arrived at a strategy which we like, this being:

  • Start our operations sometime in March.
  • Use two vessels, unfortunately we can get the two we’d like though, so we’re using a slight cheaper, slightly less capable vessel as our second.
  • Modify the capable vessel so it can carry more foundation units per trip (3).

However, we saw that the division of labour we’d set wasn’t optimal and that we off hired one of our vessels early and lost some of the advantage gained by this strategy. Read more >

Analysing Wind Farm Foundation Installation – Part 6: Work Faster – Two Vessels On Hire

As we’ve moved through this analysis process and applied Mermaid to the consideration of how we can baseline and improve our performance two main objectives have repeatedly arisen:

  • Work entirely in the spring and summer to reduce winter downtime.
  • Maximise the time spent performing offshore operations when favourable conditions occur by reducing the number of transits required.

Here we are going to perform two simulations which it is hope will improve our performance.

The Simulations

There are two scenarios under consideration here:

  • Two vessels operating, both vessels can carry a set of foundations at a time, one vessel is from the base case, the other is a different, slightly less capable vessel (i.e.
Read more >

Analysing Wind Farm Foundation Installation – Part 5: Reduce Transits to Improve Performance – Offshore Resupplies

In this post we’re going to look at bringing the foundations to the installation vessel at site.  It’s thought that, as with carrying more components, we can increase the working time by transiting less.  If another vessel (a barge and tugs) brings components to the main vessel the transit requirements are reduced, although it’s worth noting that offshore transfers of this type are quite strictly limited; the trade-off between transit reduction and sensitive operations is the main concern here.

The Simulation

Our base case simulation includes the transfer of installation components to the installation vessel from a storage barge in the port.  Read more >

Analysing Wind Farm Foundation Installation – Part 4: Improve Performance – Split Installation

In the last post in this series we identified that even with a larger carrying capacity, our work force was still unable to fully exploit the preferable summer weather and that all start options performed at least some work during the winter.  In this post we’re looking at splitting our installation process into two halves.

The Simulation

To see if we can gain a performance improvement by better exploiting the summer season we are going to install the foundations in two batches of 36.  Read more >

Analysing Wind Farm Foundation Installation – Part 3: First Attempts to Improve Performance – Larger Carry

Continuing the series of posts on the analysis of offshore wind turbine installation methods, this post looks at the improvements, if any, which can be gained by increasing the carrying capacity of the installation vessel.  It is thought that time spent transiting between the vessels home port and the wind farm could be better spent on performing the installation operations, particularly in the summer months when favourable weather occurs.  To do this we’re looking at increasing the on station time by allowing the vessel to carry more monopiles and transition pieces. Read more >

Analysing Wind Farm Foundation Installation – Part 2: Initial Results

We’re looking at ways in which we can install the foundations for a North Sea offshore wind farm and using Mermaid to make decisions on the vessels and the strategy which best suit our needs.  In the previous post in this series we discussed the base case for this analysis process, this being our first look at how we might perform the work.

In this post we’re going to take a look at the results of the analysis we ran last time and we’ll try to work out how, and indeed if, we can improve things. Read more >

Analysing Wind Farm Foundation Installation – Part 1: Introduction to Analysis

This is the first in a series of posts looking at how we can use Mermaid to:

  • Analyse a large offshore operation;
  • Make decisions about which vessels and strategies we want to use;
  • Optimise our offshore operation.

We’re going to perform a series of simulations to help determine what vessel and strategy we should use and when we should perform the work.  This is a fictitious case so we’ll throw a few constraints and assumptions in as we go just to make it interesting. Read more >