Relative Assessment of the Cost of Reservation of Renewable Energy Sources

Abstract

The generation of electricity by solar and wind power plants depends on natural conditions, and therefore there are problems with their participation in the process of balancing the modes of electric power systems (EPS). It is difficult for them to carry out the forecasted and approved hourly generation schedule for the next day with the specified accuracy. The UES is forced to keep a capacity reserve to compensate for deviations of renewable energy sources (EPS) from the projected generation schedule. Since these deviations can be both larger and smaller than the permissible ones, it is by this criterion that we can choose and form a means to balance the EPS regimes. The paper proposes a method for researching backup measures of renewable energy sources with unstable generation in EPS. The criterion of optimality for comparing RES reservation methods is their relative costs 
 Among the ways of reserving RES, system reserve is generally used (mainly the maneuverable capacities of thermal and hydroelectric power plants), but since it is not enough, it is suggested to use other means of reserving power available today: electrochemical electricity storage, hydrogen and biogas technologies.
 Mathematical models based on the theory of similarity and the criterion method have been developed to analyze the technical and economic efficiency of certain means of reservation. The criterion method is preferred due to the fact that, with minimal available initial information, it provides an opportunity to compare different methods of reserving RES generation and determine the optimal ones. The method makes it possible to assess their proportionality, as well as to determine the sensitivity of costs to the power of reservation methods.
 Criterion models have been formed that make it possible to build the dependence of the costs and reserve means of variable RES generation on the capacity of the reserve means.. Such dependencies make it possible to more reasonably choose certain reservation methods at the first stage in accordance with the characteristics and requirements of the UES. They can be clarified if the price indicators that are valid at the moment and for the near future are known.