Wind Energy Feasibility Study - Town Of Orleans

Wind Energy Facility Economic AnalysisTown of Orleans, MAturbine projects. It is advisable to review this figure when the terms of the warranty areestablished.Turbine icing and blade fouling. Serious icing conditions can prevent a wind turbine fromoperating, as the turbine shuts down if there is imbalance of the blades. Undoubtedly there is theprospect for ice to collect on turbine blades in a location such as the Orleans watershed. Threedays has been given as the likely total occurrence per year of icing events, which equates to anavailability of 99.2%. Blade fouling is not expected to occur, as this is primarily a problem invery hot climates where severe insect fouling can affect the aerodynamics of the turbine blades.Substation maintenance. The connection to the grid may have to be temporarily shut down formaintenance.Utility downtime. Most wind turbines will fail to efficiently produce energy during lower windconditions when the grid does not actively supply electricity for the machine’s control systemsdue to a grid power outage. This is expected to occur, on average, approximately eight hours peryear.High wind speed hysteresis. During very high wind conditions, a wind turbine will shut downto protect its electrical and mechanical components. The machine will only restart when windconditions fall significantly below the cut-off wind speed. This factor is used to compensate forpower loss during this restarting delay. Because Orleans rarely experiences winds above the 25m/s cut-out speed, high wind speed hysteresis is not expected to have a significant effect onpower output. The factors and values used to compute turbine availability at the Orleans site aresummarized in Table 2-4.10