"Burton et al. (2011) further added that:There are two stages under design process i.e. (i) aerodynamic design and (ii)structural design. The aerodynamic design primarily features the blade geometrywhich includes airfoil family and chord, twist and thickness distribution, optimumgeometry of blade and the external surface. The aerodynamic design in turnsatisfies the first two objectives written above. The structural design consists ofblade material selection and determination of a structural cross section or sparwithin the external envelope that meets objectives four to six written above. (TonyBurton, 2011)The above two stages are interlinked. For example, in order to accommodate a sparthat is structurally efficient, the blade thickness needs to be large.The parameters affecting the optimization of wind turbine are- Rotor speed is one of the parameter that affects the small and medium sizewind turbines which are close to the properties so it is suggested that thewind turbine blade tip should not exceed 70 m/s. Now concentrating onfixed speed machine and variable speed machine individually, in variablespeed machine the high blade tip speed from 65 m/s to 70 m/s is normallyconsidered to achieve high rotor power coefficient and wind turbine powerperformance whereas for fixed speed machines, we should address the bladetip speed carefully because if the rotor moves too slowly, most of the windwill through. Thus, little power can be extracted. On the other hand if rotorturns too fast, it acts as a solid wall obstructing the wind flow, againreducing power extraction. (Ragheb, 2014)- Rotor Dimensions: The blade length and rotor radius is directlyproportional to the torque. Hence, bigger these parameters biggest thetorque produced.The rotor radius and blade variation is done keepingswept area constant. With increase in rotor radius, power coefficientincreases equally. But this takes place at higher tip speed ratios.Subsequently, at lower rotor radius and low tip speed ratio is necessary towork at maximum higher power coefficient. (Castillo, SMALL-SCALEVERTICAL AXIS WIND TURBINE DESIGN, 2011)- The airfoil performance is affected by air density, air velocity, relative windvelocity and the chord length of the airfoil. The wind turbine output isgreatly influenced by turbulence caused by the dust effect, surfaceroughness and the thickness of the airfoil. The airfoil is selected on the basisof the availability of data like angle of attack which ranges between -30 and30 degrees, also the final thickness of blade which reflects the ability ofblade to tolerate load.- Design wind speed and rated wind speed are two parts of fixed windspeed. At design wind speed the rotor power achieves its maximum output value whereas in rated wind speed the rotor power achieves its nominalpower output value. The wind turbine blade design should be such that thebest power performance can be achieved at prevailing wind speed range.Conclusion:Through this research study, we are able to conclude that for a wind turbine toperform optimally, various factors pertaining to the context of blade design need tobe controlled. Blade design analysis through BEM gives a fair blade design but CFDgives a more accurate result. Studying about the different aerodynamic, structuraland geographical factors, we conclude:- General shape of rotor remains fixed, only minor changes may occur to bladedesign and shape as and when the manufacturers feel so.- HAWT should be mounted at a minimum height of 30 feet in the absence ofany obstruction within 300 feet of range.- The rotor tip speed should not exceed 70 m/s.- Angle of attack should range between -30 and 30 degrees.- Airfoil should be thin and long but stiff in order to bear the loads.- Rotor should be light in weight.- Natural phenomena such as temperature change cannot be controlled hencea detailed geographical analysis is mandatory for the installation of windmill.- Spar should be strong in order to bear high bending loads and fatigue loads.Although these conclusions are based on studying the factors and not onexperimental basis, all the figures mentioned have been studied by experts whohave been duly cited.Works Cited:Castillo, J. (2011, december). SMALL-SCALE VERTICAL AXIS WIND TURBINE DESIGN. Tampereenammattikorkeakoulu: Tampere University of Applied Sciences.Claessens, M. C. (2006, November 9). The Design and Testing of Airfoils for Application in SmallVertical Axis Wind Turbines. Master of science Thesis.Fingersh L., H. M. (2006). wind turbine Design cost and scaling model. NREL.Gunner C. Larsen, M. H. (2002, February). Modal Analysis of wind Turbine Blades. Denmark.HEXCEL. (n.d.). Retrieved from www.hexcel.com: www.hexcel.com/solutions/wind-energy/wrootKompulsa - Science And Technology. (n.d.). Retrieved from www.kompulsa.com:http://www.kompulsa.com/factors-affecting-wind-turbine- performance/#effectofwinteronwindpowergeneration(2005). Retrieved from Aerospaceweb.org.Manwell, M. a. (2009). wind energy explained :theory , design and application. wiley.Nitin Tenguria, M. N. (2010). Design and Finite Element Analysis of Horizontal Axis Wind Turbineblade. DINDIGUL: INTERNATIONAL JOURNAL OF APPLIED ENGINEERING RESEARCH.Omar Badran, E. A. (n.d.). Evaluation of parameters affecting wind turbine power generation.Peter J. Schubel, R. J. (2012). Wind Turbine Blade Design. Nottingham: Energies.Ragheb, M. (2014, November 3). Optimal Rotor tip speed ratio.S. Tullis, A. F. (2012). Measurement of high solidity vertical axis wind turbine aerodynamic loadsunder high vibration response conditions.Tony Burton, N. J. (2011). Wind Turbine Blade Structural Engineering. Retrieved from GURIT:www.gurit.com/files/documents/3_blade_structure.pdfVicky K Rathod, P. (2004). Design & Fabrication of PVC Bladed Inexpensive Wind Turbine. IOSRJournal of Mechanical and Civil Engineering.Vipin Kumar Singh, T. T. (2013). Structural Design of a Wind Turbine Blade: A Review. InternationalConference on Global Scenario in Environment and Energy. "