Life Cycle Cost Analysis of Flexible Low-Frequency AC Transmission for Offshore Wind Power

Objective Flexible low-frequency AC (LFAC) transmission is a promising technology for long-distance power export from offshore wind farms. To quantitatively evaluate its engineering value, this study aims to develop a life cycle cost (LCC) model for LFAC technology and compare its economic performance against the conventional voltage source converter-based high voltage direct current (VSC-HVDC) solution, thereby identifying the cost-advantageous range for LFAC in typical application scenarios.

Method This paper modeled a typical medium-to-long distance offshore wind power export scenario featuring a transmission distance of 80 km and a wind farm capacity of 1,500 MW. By establishing an LCC model that encompasses initial investment, operation and maintenance, and decommissioning costs, the LFAC solution was economically assessed and benchmarked against a VSC-HVDC solution under identical conditions.

Result The results demonstrate that at a transmission distance of 80 km, the net present value of the LCC for the LFAC solution is 15.53% lower than that of the VSC-HVDC solution. This economic advantage primarily stems from reducing initial investment costs, operating expenses, and decommissioning costs.

Conclusion This study confirms that LFAC transmission is a highly competitive technical solution in the field of medium-to-long distance offshore wind power export, offering a new pathway for cost reduction in the development of future offshore wind farms.