14 June 2017
New research: The cost for operating expenditures for an offshore wind farm can fluctuate by up to factor 9.5.
An exhaustive study, which has just been published, shows that the logistics of offshore wind is both cost-intensive, heavily variable and generally speaking without financial monitoring.
”In fact, logistics is a huge risk during the entire operating calculation as you do not know the expenses. You bind yourself to 25 years of expenses based on assumptions and estimates”.
This is stated by Thomas Poulsen, Department of Materials and Production, Aalborg University, who together with Charlotte Bay Hasager, Department of Wind Energy, DTU and Christian Munk Jensen, Offshoreenergy.dk, are behind the publication ‘The Role of Logistics in Practical Levelized Cost of Energy Reduction Implementation and Government Sponsored Cost Reduction Studies: Day and Night in Offshore Wind Operations and Maintenance Logistics’.
The study of the logistics expenses by operating offshore wind farms compares 11 government sponsored studies of the total expenses by installation and operation of offshore wind farms.
”Comparing the studies conducted of the total expenses, it appears that the expenses categorised as Operating Expenditure (OpEx) fluctuate by factor 9.5. At the same time, we can see that OpEx, conservatively estimated, makes a variable part of the total expenses of 13 – 57%, says Thomas Poulsen.
”It is a heavy risk factor to include in the calculation”, supplements Charlotte Bay Hasager, senior researcher at DTU Wind energy:
”You can hardly imagine that an operator of offshore wind farms budgets for the fact that the blades or the towers can fluctuate by factor 9.5 of the price”, she says.
Focus is lacking
One of the large gains by the study is that the extent of the logistics is clarified and identified. It makes it possible to do something actively to strengthen the logistics as focus area. In this relation, the recently published study also includes the academic reporting of a project managed by Offshoreenergy.dk, which has just focused on logistics expenses within operation and maintenance of offshore wind farms.
”Knowing the extent of the logistics, we can better optimise it”, says the third of the authors of the report, Christian Munk, who is a project manager with Offshoreenergy.dk and was responsible for the project:
”When the variable is that large, which it is, it indicates that focus is not sufficient in the area. This appears from the expenses. As an example, the 24/7-project, where the offshore wind farms are serviced day and night instead of only in the daytime, have proved considerable savings by making the operation more efficient”, he says.
It is about giving the area the focus which it deserves, Thomas Poulsen thinks:
“When nobody is aware of an area, the expenses are easily getting out of control. And on the other hand, a tight focus allows you to hold back the expenses and even save money. For example, a study of logistics as share of the GNP (Gross National Product) from the USA shows as an example that by keeping focus on the logistics, it has been possible to reduce by half the expenses over a 20-year period. It is not sure that the same can be done on offshore wind logistics, but when the expenses amount to 17 – 32% of the OpEx alone, even few percentage points are worth counting”, says Thomas Poulsen.
” It is a huge risk during the entire operating calculation that you do not know the expenses. In fact, you bind yourself to 25 years of expenses based on assumptions and estimates”.
Thomas Poulsen, Ph.D. scholar, Department of Materials and Production, Aalborg University.