Potential of load management to improve the economics of wind-diesel hybrid systems

This paper investigates the possibility of fuel savings obtainable from a wind-diesel hybrid system through load management strategies. Scope for improvement in system economics by selecting the optimum wind turbine capacity for the hybrid system is also explored. Comparison of performances was carried out using the 'Hybrid2' simulation program. The study was based on a single diesel and single wind generator without any storage. The diesel was allowed to operate continuously, with a minimum loading of 40% of its rated power maintained where necessary by a dump load. The first part of the study involved selection of appropriate diesel-wind combinations for achieving highest fuel savings and/or the lowest generation costs. An economic evaluation to calculate the cost/kWh of generated energy for the different hybrid combinations resulted in determining an optimum size of wind turbine for the system. The second part of the study investigated the effect of load management strategies. The results indicate a decrease in generation cost and fuel consumption and a considerable yearly saving on the diesel costs.