Optimisation of wind turbine electrical power conversion

Abstract

With South Africa being one of the major contributors of greenhouse gases in the world due the large number of coal burning power stations, and Eskom the local electrical power utility enforcing “loadshedding” to cope with the current demand in electrical energy, it is apparent that there is a need to do research on an off–grid home powered by a renewable energy source. The renewable energy source selected for this dissertation is wind energy. The main goal is to determine if it is viable for an off–grid home to be powered by only using wind energy. Wind energy is a well established source of renewable energy in countries like Denmark and Germany. An energy usage analysis is done on a home with no energy efficient strategy. The energy wasting appliances are identified and replaced with energy efficient appliances to reduce the energy usage of the home. This indirectly reduces the size and cost of the wind generator system (WGS) required to supply the house with electrical energy. The various components of an off–grid WGS are identified and researched in terms of available technologies, efficiency and maintenance requirements. The WGS is pulled apart to view each component separately. This helps to identify the areas where the WGS can be optimised in terms of energy conversion efficiency. A WGS is assembled according to a theoretical specification (based on real life parameters) of an off–grid home with no energy efficiency strategy in place. The home is made energy efficient by identifying and replacing the energy wasting appliances with energy efficient appliances. The components of the off–grid WGS are sized and selected based on their performance characteristics. The cost of the WGS is calculated for a period of 20 years. The cost of the WGS is compared to the cost of supplying the home with electrical energy from a fuel generator for the same period. The cost is also compared to supplying the home with electrical energy from the utility for the same period.