Performance Characteristics of a Kite-Powered Pump

Abstract

A kite-powered pump which employs a kite to convert wind energy into potential energy of water has been studied to determine its performance characteristics and see if the steady-state operation is feasible. Governing equations describing the motion of the pump in both the ascent and descent modes have been developed assuming that the tether is inflexible and that its profile is a straight line. These equations have been solved numerically to assess how performance parameters of the pump, such as output power, load-carrying capacity and cycle time vary with the pump stroke, kite weight, kite’s lift to drag ratio (CL /CD ), initial tether length and tether angle of inclination. Further, conditions for steady-state operation of the pump have been specified. The results show that (i ) the maximum power during the ascent is produced when the kite motion is approximately crosswind, (ii ) the steady-state cyclic motion of the kite pump is feasible with a net power output, (iii ) the average pump power increases at a rate slower than (CL /CD )2 as (CL /CD ) increases, and (iv ) the pump power peaks with the kite weight.