The article presents calculations and power flow of a real virtual power plant (VPP), containing a fragment of low and medium voltage distribution network. The VPP contains a hydropower plant (HPP), a photovoltaic system (PV) and energy storage system (ESS). The purpose of this article is to summarize the requirements for connection of generating units to the grid. Paper discusses the impact of the requirements on the maximum installed capacity of distributed energy resource (DER) systems and on the parameters of the energy storage unit. Firstly, a comprehensive review of VPP definitions, aims, as well as the characteristics of the investigated case study of the VPP project is presented. Then, requirements related to the regulation, protection and integration of DER and ESS with power systems are discussed. Finally, investigations related to influence of DER and ESS on power network condition are presented. One of the outcomes of the paper is the method of identifying the maximum power capacity of DER and ESS in accordance with technical network requirements. The applied method uses analytic calculations, as well as simulations using Matlab environment, combined with real measurement data. The obtained results allow the influence of the operating conditions of particular DER and ESS on power flow and voltage condition to be identified, the maximum power capacity of ESS intended for the planed VPP to be determined, as well as the influence of power control strategies implemented in a PV power plant on resources available for the planning and control of a VPP to be specified. Technical limitations of the DER and ESS are used as input conditions for the economic simulations presented in the accompanying paper, which is focused on investigations of economic efficiency.

This paper analyzes the technical and economic possibilities of integrating distributed energy resources (DERs) and energy-storage systems (ESSs) into a virtual power plant (VPP) and operating them as a single power plant. The purpose of the study is to assess the economic efficiency of the VPP model, which is influenced by several factors such as energy price and energy production. Ten scenarios for the VPP were prepared on the basis of the installed capacities of a hydropower plant (HPP), rooftop solar photovoltaic (PV), and energy-storage system (ESS), as well as weather conditions, in Poland. On the basis of technical conditions, it was assumed that the maximum power capacity of the ESS equaled 1.5 MW. The economic efficiency analysis presented in this paper demonstrated that, in seven years, the VPP will achieve a positive value of the net present value (NPV) for a scenario with 0.5 MW battery storage and rainy summers. Furthermore, sensitivity analysis was conducted on price factors and DER production volume. The price variable had a major impact on the NPV value for all scenarios. The scenario with a 0.5 MW battery and typical summers was highly sensitive to all factors, and its sensitivity decreased as the ESS capacity grew from 0.5 to 1.5 MW.

This paper investigates the profile of end user of renewable energy sources (RES) among Polish households. Users differ in their sex, age, economic status, knowledge about energy, their attitudes toward RES and pro-ecological behavior therefore our focus was on exploring segmentation criteria. The main determinants of willingness to install small-scale RES among households were assumed as segmentation criteria. The research identified the correlation between the households’ willingness to install RES and (1) socio-economic and energy awareness variables, (2) pro-ecological and pro-effectiveness behaviors variables. The main determinants of RES adoption were explored using empirical analysis with data collected by the survey among 960 households in Lower Silesia, a southwest region in Poland in November and December of 2015. The importance of the variables was verified by a logit model. The discovery of the user profile is vital to obtain knowledge about users of small-scale generators to provide them personalized offer. The finding from this study could be valuable for local authority’s energy utilities that are involved for increasing the adoption rate of RES among households and for (e.g., services companies installing RES) that are interested in increasing number of RES installations.

E3S Web of Conferences, open access proceedings in environment, energy and earth sciences

The pro-ecological and pro-saving behavior of households as energy consumersThe aim of the article is to indicate the changes related to households’ behavior linked to energy saving and pro-ecological activities. Therefore, the authors conducted acomparison analysis of the results of the nationwide Polish research about Polish ecological awareness and identified — as part of the Polish National Science Centre NCN project called “Modelling prosumers’ behavior on theenergy market” — pro-economical attitudes of households. The first part of this paper pre­sents the opinions of Poles about the possibilities of development of the different kinds of energy sources in Poland, taking into special consideration the development of renewable energy sources. In the second part of this paper the authors describe households’ behavior connected with saving energy. They analyzed pro-economical behavior such as: switching off lights in empty rooms, un­plugging phone chargers after use, using economical bulbs and unplugging devices that are not in use. The diversifying variables of behavior are: sex, age, income. The analysis of households’ behav­ior was supplemented with the analysis of pro-economical attitudes of Wroclaw university students.

E3S Web of Conferences, open access proceedings in environment, energy and earth sciences