Energy yield and cost analysis of small scale wind turbines

This paper seeks to explore the attractiveness of small-scale wind turbines in the current economic climate. In order to do this, three pieces of information must be known: (1) the cost of the system; (2) the annual energy yield of the system; (3) the value of that energy yield. An internet based search was conducted to establish current market prices for (1) and (3). The annual energy yield is more difficult to determine, and in this paper a Weibull probability distribution of wind speed, combined with the turbine's power characteristic, has been used to estimate it. This analysis has been carried out on a number of small-scale turbines that are currently on the market and the results have been compared to a family of generic turbines with ideal performance characteristics to assess whether the manufactures' performance claims are accurate. The income generated and the level of CO(2) abatement has also been calculated. It was found that a 2.5-3kW turbine could supply all the energy needs of an average household, however the current cost of the system is expensive compared to the cost of buying the energy from the grid, leading to a payback period of similar length to the design life of the turbine.