Energy Cost Estimation of Small Wind Power Systems—An Integrated Approach

Small wind power systems (SWPSs) of 100 kW or below are critical in addressing increasing global energy consumption and pressing greenhouse gas emission issues. Energy cost, i.e., cost of generating 1 kWh or MWh of electricity is an important consideration for design, development, and operation of SWPSs. Various methods for energy cost estimation have been reported, but they typically consider only some aspects of the wind power systems. This paper presents a novel energy cost evaluation methodology for SWPSs, integrating wind turbine energy production, system component efficiency, cost, and reliability together into a single comprehensive model. Monte Carlo simulation is applied to produce random functional intervals or failure intervals, considering the statistical nature of reliability. As compared with previous methods with the segregated and deterministic approaches, the new method comprehensively analyzes the energy costs of SWPSs through an integrated and stochastic approach. The proposed methodology is applied to studies of various SWPS configurations at a typical 30-kW level for both fixed-speed and variable-speed operations. The simulation results present an overview of the investment required for an SWPS over its installed lifetime, reveal cost effectiveness of different configuration options, and provide a benchmark for energy cost evaluation of wind power systems.