DEVELOPMENT OF A LOW COST, LOCALLY MANUFACTURED ROTOR BLADE FOR A SAVONIUS WIND PUMP

Abstract

Studies  indicate  that  vertical  axis  wind  turbine  provide  a  more  reliable  energy  conversion  technology,  as compared  to  horizontal  axis  wind  turbine,  especially in  areas  of  lowly  rated  and/or  uncertain  wind  speeds, mostly arid  and semi-arid areas.  The  challenge however is  the  development  of an  efficient and cheap  rotor blade which is currently not manufactured in Kenya. The objective of this research was to identify local wind turbines manufactures  in  Kenya; design a savonius  rotor  blade; locally  develop a  Savonius vertical axis wind turbine rotor blade for wider use in Kenya and to analyze the cost of the developed Savonius rotor blade. In achieving  these,  a number  of  methodologies  including:   field  questionnaires,  empirical  design  calculations, prototype  development  and  laboratory  testing  were  used  to  develop such  a  rotor  blade.  Laboratory  tests using a tachometer and Hygro- thermometer were able to provide a number of interesting results including: Ability to pump water of four cubic meter per day for 200 people, costing less than KES 300,000/= per unit and hydraulic  power capability  of  less than 1  kW.  Field  tests for  the  system are  to  be undertaken  soon  but it is projected  that  the  laboratory  results  will  not  differ  significantly  from  the  field  results.  In  conclusion  the research  work  has  been  able  to  develop  a  wind  conversion  technology  that  makes  the  system  affordable, locally manufactured and more efficient than current  existing system. A key achievement of the system has been  the  ability  to  provide  the  local  small  wind  energy  sector  a  process  and  material  matrix  to  be  used  in developing  of  more  efficient  vertical  axis  wind  turbine  blades  that  are  more  adaptable  towards  Kenya’s average wind speed of ≤ 4m/s. 

Key words: Savonius, vertical axis wind turbine, Green energy, Energy conversion technology, non-renewable