35 Pages

Introduction: Where there’s a wind there’s a way – design options and opportunities

The power in ‘free-flowing’ wind (i.e. not locally accelerated) is given by the well-known kinetic power term ½m.v2 where m is the mass flow rate (kg/s) of the air passing through the swept area of the turbine blades and v is the velocity of the free wind (m/s). For convenience the wind turbine power equation is expressed in terms of swept area. Therefore the mass m is replaced with ρAv where ρ is the density of the air (kg/m3) and A is the swept area of the blades (m2).