The Carbon Trust is seeking a contractor to undertake an offshore wind farm R&D study, called ‘The Maximising Lifetime Asset Integrity Study’.
It is becoming more apparent within the Offshore Wind industry that several operating offshore wind farms are experiencing a higher level of structural issues than originally anticipated. This is resulting in not only increased maintenance and repair activities thus increasing the overall OPEX (Operational Expenditure), but also spreading doubt on the structural integrity of the balance of plant and certainty of reaching the assumed 25 year lifetime.
This study aims to identify which issues are having the greatest impact on the structural integrity for the balance of plant for the 4 OWA supported foundations, a standard jacket and a standard monopile. The aim is to understand the cost benefit of mitigating potential issues and achieving full operation for 25 years lifetime and beyond.
The Carbon Trust will coordinate the data collection of existing failures detected by OWA partners in a confidential manner. The trade-off between more conservative design (increasing CAPEX (Capital Expenditure)) and less structural O&M (lowering OPEX) or optimising the design (lowering CAPEX) but having more extensive O&M operations (increasing OPEX) need to be better understood. Different O&M strategies (e.g. inspection intervals) will be defined and the overall cost (CAPEX + OPEX) will be analysed in order to understand the best approach to follow for each structure from the ones considered in this project.
This study will also focus on understanding the risks associated with the balance of plant for OWA supported foundations and monopiles in Round 3 offshore sites.
The objectives of this study are to: Assess the severity and likelihood of risks that may reduce the operating life of an offshore wind farm, focusing on balance of plant (including substations, cables, concrete and steel foundations, secondary steel such as boat landings, connection and tower); Identify mitigating actions that can be taken in design stage to reduce the risks. Identify remedial actions that could be taken to address issues, depending on when they are detected; Revise scenarios and assumptions of current designs and see if including O&M inspections would decrease the overall costs; Consider structural integrity management strategies to minimise the costs; Analyse the trade-off between increasing CAPEX vs. increasing OPEX; Identify strategies to extend the operating life of an asset.
Offshore WIND Staff, September 3, 2013; Image: Town of Hull