The increasing number of distributed energy resources in form of solar power plants has led to uncontrolled power production. Therefore, the grid operator has less and less capabilities to regulate power production. Due to the fact that the active power of solar power plants is directly dependent on the intensity of solar radiation, their production is very volatile. As a countermeasure to reduce the effect of volatile production it will be necessary to include additional regulated elements to the power grid. Regulated elements such as battery storage, control loads, gas power plants and other devices represent additional costs in the construction and management of the electrical network.
In my master's thesis, I discussed a non-classical method for reducing the production volatility of two solar power plants. As a regulated element, a small hydroelectric power plant capable of storing 3,7 MWh of energy was used. With the use of numerical program, I have analysed the operating principle of a virtual power plant. The data on which the analyses were based, cover the period of one year. Using two different solar radiation forecasts, I calculated two different predicted active powers of the solar power plants. The task of the regulated element in the virtual power plant was to cover any deviation between predicted and actual active power of the solar power plants. In the analysed model, I took into account all the technical limitations of the production facilities, as well as the economic factor of operating the hydroelectric power plant.
A comparison between the predicted and the actual active power of the virtual power plant has shown that in case of unregulated active power of the hydroelectric power plant, the virtual power plant follows the prediction only in 10% of the operating time. With the use of the best method for prediction of the active power of a solar power plants and with the use of the regulation of the active power of a hydroelectric power plant, this share increases to 65%. The analysis reveals that such a system is capable of reducing the volatility of solar power plants production, but to a limited extent