Comparing Levelized Cost of Energy for a 200 MW Floating Wind Farm using Vertical and Horizontal Axis Turbines in the Northeast U.S.A.

Abstract

Abstract The technology to engineer, fabricate and install offshore floating wind turbine exists and is feasible for all components. Applying lessons learned from offshore oil and gas projects with respect to engineering execution options, competitive supply and reduction in life cycle costs makes offshore floating wind a commercially viable energy supply in regions with relatively high electricity prices or in regions that have other geographical or resource constraints to bringing additional energy supply on-line. However, while horizontal wind turbine (HAWT) technology is developing rapidly and driving down cost, it may be possible to further drive down offshore floating wind costs by choosing a vertical axis wind turbine (VAWT) technology. VL Offshore has developed a cost effective 5 MW floating foundation, Y-Wind semi for HAWT. In this study, the LCoE (Levelized Cost of Energy) of the Y-Wind semi with 5 MW HAWT is compared against the same foundation type with a 5 MW VAWT. For the present work, a 200 MW wind farm, located about 10km off shore the Northeast U.S. at a water depth of 100m is selected. This water depth exceeds the current commercial limits for fixed foundations for offshore wind. LCoE is estimated using the tool developed by NREL, considering all the cost parameters of foundation and mooring CAPEX, installation, operation and maintenances, in-field and export power cables, capacity factors, turbine layouts, substation, discount rate, cost escalation rate, current electricity price and design life. The LCoE results indicate that a 5 MW VAWT foundation will be more commercially viable than a comparable 5 MW HAWT foundation. The LCoE values compare favorably to the LCoE values for most electricity prices in the Northeast states.