When the power delivered by the wind turbine is greater than the load, the battery enters a charging mode. When there is unmet demand, the battery begins to discharge. The size of the wind turbine is selected such that at the end of one year the net charge in the battery is positive and the AMI-193 does not need to import external electrical energy.
A thermodynamic model of the wind-battery system was constructed using EES. The model contains three input variables over 365 days: 1) electricity demand per household, 2) wind speed, and 3) ambient temperature. Model parameters and life-cycle emission factors are principle of segregation provided in Table 3 and Table 4, respectively.
Wind-battery model parameters.ParameterValueBetz limit for a wind turbine0.59Charging efficiency of the battery0.85Cut-in wind speed5 m s−1Cut-out wind speed23 m s−1Discharging efficiency of the battery0.85Electric generator efficiency0.92Mechanical efficiency of a wind turbine0.60Power coefficient of a wind turbine0.45Rated wind speed15 m s−1Rotor radius19 mFull-size tableTable optionsView in workspaceDownload as CSV