Energy system design of offshore natural gas hydrates mining platforms considering multi-period floating wind farm optimization and production profile fluctuation

Natural gas hydrate has potentially become a clean energy source that can replace fossil fuels in the future. Offshore natural gas hydrates mining platforms are usually energy-intensive and wind power has been used as the main source of energy supply. However, there have been a limited number of studies investigating the energy systems in these offshore platforms, and the optimal implementation of wind turbines has not been considered. In this work, a floating wind farm is combined with gas turbines to supply energy for the natural gas hydrate mining platform. Since the position of floating wind turbines can be adjusted, a multi-period optimization method is proposed to consider the changes in wind resources and production profiles in different periods. In addition, the performances of different types of wind turbines are also investigated in the optimization. The minimum total cost of energy is set as the objective function in this method. Considering that the number and layout of wind turbines are affected by moving costs. When the moving costs per unit distance is 40 euro/MW, the results showed that six wind turbines are required for stable operation of the platform, and the power generated by the wind turbines accounts for 77.59% of the total power supply in the whole period. From the results of case, compared with directly burning natural gas, wind power generation can effectively reduce the power generation cost of the platform.