Serbia: The most cost-effective power supply solution of isolated consumers using hybrid systems with wind turbines, batteries and diesel generators

, News Serbia Energy

For many consumers it is more cost-effective to install multiple isolated power supply systems, rather than connect to the network. In this case it is necessary to conduct an analysis with a view to designing a cheaper isolated system, able to always meet the demand for electricity. The paper, The most cost-effective power supply solution of isolated consumers using hybrid systems with wind turbines, batteries and diesel generators, analyses a consumer located on a site with good wind resources, whereas the main source of electricity are small wind turbines. To ensure uninterrupted power supply, batteries storing electricity were used, together with a diesel generator. The consumer was described by the mean hourly consumption during the year. The aim was to optimally dimension each component of the system to ensure uninterrupted supply of consumers, whereby the optimization criterion was the cheapest system. The analysis was performed with and without possible demand management, in order to determine the profits brought by demand management possibilities.

The authors of this paper, D. Kotur and J. Mikulovic showed a new method for optimal dimensioning of hybrid systems with wind turbines, diesel generator and batteries. Unlike most papers, optimising a system by applying pre-determined empirical formulas, in this paper, the optimization is done on the basis of the behaviour of the current system similar to the projected future. In this way, optimal characteristics of system elements may be determined, as the calculation is based on the consumption diagram likely to characterize the consumer. In general, the future production and consumption diagrams need not match the data used in the paper, however, given that the analysis is performed for the entire year, it may be considered that this way wind stochastics and consumption are largely reduced.

Based on the optimization results, it may be seen that the price of electricity is not much higher than the one obtained by purchasing from the grid. For any particular case, it may be determined whether the more expensive solution is network connection or developing a separate system. The analysis provided the expected solution – electricity price is higher when demand management is not performed than when it is performed. However, this difference is not large.

Analysis results demonstrated that in the high wind speed days, speeds are typically high during the entire day, so that at any hour there will be enough wind resources to cover consumption. On the other hand, when the weather is calm, meaning there is no wind, it remains like this almost during the entire day. As a result, diesel generators may be used throughout the day. However, savings of almost 20 percent cannot be considered negligible, wherefore it is concluded that demand management pays in the case of a single household, transmits