WIND ENERGY HARVESTING AND ENERGY-WATER NEXUS USING FLUID POWER WITH A WIND TURBINE AS THE PRIME MOVER

As the main study in this report, it provides in-depth analysis regarding the techno-economic benefits of replacing the mechanical gearbox with a hydraulic transmission in an offshore system. Our analysis shows that hydraulic transmissions are particularly beneficial for offshore applications: (i) relocating 35.3% of the nacelle mass to the base, thus moving the center of gravity toward the ground level, (ii) diminishing operation and maintenance costs, and (iii) replacing now-redundant power electronics. These three benefits contribute to saving between 3.92 and 18.8% on the Levelized Cost of Electricity for average cost offshore wind turbines. Additionally, the study presents the design, modeling, and dynamic simulation of a horizontal axis wind turbine fitted with hydrostatic transmission (HT) and its response to atmospheric boundary layer (ABL) and low-level jet (LLJ) wind velocity profiles. An HT provides distinct advantages associated with a significant reduction of nacelle mass by moving the generator to the tower base, eliminating the gearbox, reducing maintenance cost, providing a constant speed to drive the generator, and lowering the center of gravity for offshore applications. To complement and validate the previous approach, in-field experiments are used to assess the operational performance and response to turbulent wind flow of the first actual hydraulic wind turbine in the country. The use of a cyber-physical system built in the laboratory provides proof of concept of the integration of energy-water nexus using fluid power and a wind turbine as the prime mover. Future work to complete successfully the ongoing work is described. Finally, it is included a summary of the technologies developed done in parallel with the main research topic.