A Review of Life Extension Strategies for Offshore Wind Farms Using Techno-Economic Assessments

Benjamin Pakenham,Anna Ermakova,Ali Mehmanparast

doi:10.3390/en14071936

Abstract

The aim of this study is to look into the current information surrounding decommissioning and life extension strategies in the offshore wind sector and critically assess them to make informed decisions upon completion of the initial design life in offshore wind farms. This was done through a two-pronged approach by looking into the technical aspects through comprehensive discussions with industrial specialists in the field and also looking into similar but more mature industries such as the Offshore Oil and Gas sector. For the financial side of the assessment, a financial model was constructed to help portray a possible outcome to extend the life for a current offshore wind farm, using the existing data. By employing a techno-economic approach for critical assessment of life extension strategies, this study demonstrates the advantages and disadvantages of each strategy and looks to inform the offshore wind industry the best course of action for current wind farms, depending on their size and age.

Highlights

IntroductionWind farms for UK energy generation in offshore sites (as opposed to onshore/land based) have only been commercially viable for 30 years or so and the scale of the farms and the size of turbines have dramatically increased in the last 15 to 20 years
Wind farms for UK energy generation in offshore sites have only been commercially viable for 30 years or so and the scale of the farms and the size of turbines have dramatically increased in the last 15 to 20 years
Following a simplistic approach which is easy to understand by a broader range of engineers and scientists working on the design and assessment of offshore wind turbines, this study aims to provide an overview of the current knowledge on issues around the end of the expected life and set out the advantages and disadvantages of each of the possible scenarios

Summary

Introduction

Wind farms for UK energy generation in offshore sites (as opposed to onshore/land based) have only been commercially viable for 30 years or so and the scale of the farms and the size of turbines have dramatically increased in the last 15 to 20 years. The onshore wind industry gives a framework for turbine decommissioning costs, one other factor that crucially impacts the offshore sector is environmental regulations. When first-generation offshore wind farms were installed, decommissioning costs were inaccurately estimated due to limited data points available at that time. London Array was used as the example, because it is a large farm, and the financial data are available in the public domain. It is generally accepted that there is a discount rate of 4% within the offshore wind industry [46], this is used both in costs and within energy output per year. There is a lot of debate about the decommissioning costs, for the model £400,000 per MW has been used— is this used in [46], but it is the middle of the range discussed in Section 3.2.2 above

Objectives

Results

Discussion

Conclusion