Impact of energy storage devices on energy price in decentralized wind-diesel utilities

The most widely spread method of supplying the customers in isolated areas is to use single or multiple diesel generators with constant or variable speed. The price of energy in such areas is highly influenced by the cost of fuel transportation to the place of consumption. We propose an approach to reduce this price by complementing the diesel generators with wind turbines and high-capacity energy storage devices. We create a model to define the proportion between the installed capacities and to provide the proper sizing of elements. The paper studies the case of an isolated area in central Russia, where the fuel transportation share of energy price reaches 65%. We propose a new energy supply system, which includes diesel generators, wind turbines and energy storage devices. We study the system statistically and model it in Homer software. To decrease the capital and operating costs, we introduce the specific algorithm: the diesel generator operates only when wind turbines are not covering the load and energy storage device is exhausted. We test the proposed algorithm using MATLAB to obtain both economic and technical operation results. The economic modeling then continues the system evaluation. We evaluate the investment criteria and define the new minimum price for electricity. The paper is concluded by a systematic analysis of the results and remarks towards the efficiency of investment into the new equipment.