Economic and operational implications of a complex of wind-driven generators on a power system

An assessment is presented of the technical and economic implications of integrating a sizeable complex of aerogenerators into a power system. An important economic and operational factor is the variable and uncertain nature of the wind. However, it is shown that the effects of the more rapid fluctuations are largely mitigated by the incoherency of different machine outputs; a diversity factor is defined in terms of the spacing of an array of machines and the turbulence length scale. In contrast, the slower variations are shown to require a significant enhancement of the operational reserve capacity but not to necessitate the addition of dedicated storage, to accommodate wind-power penetration up to about 20% of maximum demand. The increased uncertainty of the residual generation, over the scheduling period, significantly affects the economics of utilisation of pumped-storage and gas-turbines as standby plant. The results of an analysis of a year's data, pertaining to demand and wind speed at 4 well separated sites, are presented. Finally, those principal system aspects, that require detailed evaluation, are identified and discussed.