An economic assessment framework for decommissioning of offshore wind farms using a cost breakdown structure

Purpose As wind power generation increases globally, there will be a substantial number of wind turbines that need to be decommissioned in the coming years. It is crucial for wind farm developers to design safe and cost-effective decommissioning plans and procedures for assets before they reach the end of their useful life. Adequate financial provisions for decommissioning operations are essential, not only for wind farm owners but also for national governments. Economic analysis approaches and cost estimation models therefore need to be accurate and computationally efficient. Thus, this paper aims to develop an economic assessment framework for decommissioning of offshore wind farms using a cost breakdown structure (CBS) approach. Methods In the development of the models, all the cost elements and their key influencing factors are identified from literature and expert interviews. Similar activities within the decommissioning process are aggregated to form four cost groups including: planning and regulatory approval, execution, logistics and waste management, and post-decommissioning. Some mathematical models are proposed to estimate the costs associated with decommissioning activities as well as to identify the most critical cost drivers in each activity group. The proposed models incorporate all cost parameters involved in each decommissioning phase for more robust cost assessment. Results and discussion A case study of a 500 MW baseline offshore wind farm is proposed to illustrate the models’ applicability. The results show that the removal of wind turbines and foundation structures is the most costly and lengthy stage of the decommissioning process due to many requirements involved in carrying out the operations. Although inherent uncertainties are taken into account, cost estimates can be easily updated when new information becomes available. Additionally, further decommissioning cost elements can be captured allowing for sensitivity analysis to be easily performed. Conclusions Using the CBS approach, cost drivers can be clearly identified, revealing critical areas that require attention for each unique offshore wind decommissioning project. The CBS approach promotes adequate management and optimisation of identified key cost drivers, which will enable all stakeholders involved in offshore wind farm decommissioning projects to achieve cost reduction and optimal schedule, especially for safety-critical tasks.

Life Cycle Cost Analysis and Optimization of Modular Substation

Due to the lack of high standardization and specialization, the production scale of modular substation is difficult to meet the established requirements. Compared with traditional substation construction, there are still practical problems such as high production costs. Therefore, it is still difficult to promote modular substation. Considering the life cycle of modular substation project, Cost Breakdown Structure (CBS) and Engineering Breakdown Structure (EBS) of the modular substation were defined through literature reading and data analysis. Then use the life cycle cost mapping model to further determine the mapping relationship between CBS and EBS. Finally, the connotation and goal of the life cycle cost optimization of modular substation were proposed, which can effectively promote the cost management of modular substation projects and optimization.

Life-cycle cost as basis to optimize waste collection in space and time: A methodology for obtaining a detailed cost breakdown structure

Extensive research has been carried out on waste collection costs mainly to differentiate costs of distinct waste streams and spatial optimization of waste collection services (e.g. routes, number, and location of waste facilities). However, waste collection managers also face the challenge of optimizing assets in time, for instance deciding when to replace and how to maintain, or which technological solution to adopt. These issues require a more detailed knowledge about the waste collection services’ cost breakdown structure. The present research adjusts the methodology for buildings’ life-cycle cost (LCC) analysis, detailed in the ISO 15686-5:2008, to the waste collection assets. The proposed methodology is then applied to the waste collection assets owned and operated by a real municipality in Portugal (Cascais Ambiente – EMAC). The goal is to highlight the potential of the LCC tool in providing a baseline for time optimization of the waste collection service and assets, namely assisting on decisions regarding equipment operation and replacement.

Co-digestion of algae biomass for production of biogas and fertilizer: Life Cycle Cost Analysis

The purpose of this article is to determine and assess<em> </em>Life Cycle Costs of biogas and fertilizer produced in anaerobic digestion of biomass. General Cost Breakdown Structure for anaerobic digestion plant is described for better understanding of the system. Main cost categories discussed in this study are: Investments; Design, construction and dismantling costs; Maintenance, Operation and Transportation costs. Results showed that Design, construction and dismantling costs have the biggest share in Total Life Cycle Cost (TLCC) per cubic meter of biogas. This category also has the biggest influence on TLCC of fertilizer. Investment costs are the second most significant cost category.

The Role of Cost Breakdown Structure in Life Cycle Cost Model

This paper highlights the basic process of developing a life cycle cost model and the role of cost breakdown structure for water distribution pipeline networks. A life cycle cost is the total cost of owning an asset during its predicted useful life, while a cost breakdown structure illustrates all the costs emerged in each single phase of the asset’s life cycle cost. Its purpose is to identify, define and organize all cost elements to be taken into account in a life cycle cost. Each cost element included in developing a cost breakdown structure will also be discussed in this paper.