U.P.B. Sci. Bull., Series C, Vol. 74, Iss. 1, 2012 ISSN 1454-234x OPERATIONAL PARAMETERS EVALUATION FOR OPTIMAL WIND ENERGY SYSTEMS DEVELOPMENT Ciprian NEMEŞ 1 , Florin MUNTEANU 2 A method based on maximization of normalised average power is proposed to establish the operational parameters of wind turbine. The method is a compromise between those operational parameters that provide the highest values of the capacity factor and the rated power. The method can be used in developing stage of wind energy system, being a useful tool to make an adequate choice of the wind turbine with optimal operational parameters, which yield the highest amount of energy. Keywords: Wind energy, capacity factor, normalized average power. 1. Introduction In the last decades, a growing interest in renewable energy resources has been observed. Unlike other renewable energy sources, wind energy has become competitive with conventional power generation sources and therefore the application of wind turbine generators has the highest growth among other sources. Wind is one of fastest growing energy source and it is considered as an important alternative to conventional power generating sources. The energy production from a wind energy system depends on many factors. These factors include the characteristics of the wind profile, and most importantly, the operational parameters of the wind turbine generator itself. The suitability of a wind turbine to a site involves designing of wind turbine’s operational parameters exactly according to the wind characteristics of the site. One more applicable method is to match a specified site with a suitable wind turbine among existing ones. Numerous criteria have been proposed for the suitability procedure. Some authors determined the wind turbine generator’s parameters at maximum capacity factor or at maximum density rated output power [1,2], between these two methods there is a complementarity. Thus, if a higher capacity factor is desired, then turbine’s rated speed cannot be chosen too high. In this case, even if the wind turbine operates at rated power for most of the time, not too much of energy in higher speed wind will be captured. On the other hand, if the capacity factor is 1 Lecturer, Electrical Engineering Faculty, Technical University of Iasi, Romania 2 Prof., Electrical Engineering Faculty, Technical University of Iasi, Romania