Marek Roch

This paper presents a computationally efficient two-stage analytical framework for predicting daylight performance in buildings. It is designed to support real-time applications in smart lighting and intelligent building management systems. This approach combines a facade lighting model—driven by solar geometry and atmospheric transmittance—with an interior light distribution module that represents the window as a discretized light source. This formulation provides a lightweight alternative to computationally intensive ray tracing methods. It allows rapid estimation of spatial lighting patterns with minimal input data. The framework is validated using a one-year measurement campaign with class A photometric sensors in three facade orientations. The facade module achieved an average relative error below 15%, while the interior lighting model yielded an RMSE of 83 lx (≈10% error). The integrated system demonstrated an overall average deviation of 18.6% under different sky and season conditions. Owing to its low computational complexity and physically transparent formulation, the proposed method is suitable for deployment in smart building platforms, including daylight-responsive lighting control, embedded energy management systems, and digital twins requiring fast and continuous simulation of daylight availability.

The expected increase in electric vehicles necessitates an expansion in charging stations. However, this increase could introduce issues to the power grid, such as the deterioration of voltage stability and an increase in microgrid loading. To address these issues, innovative solutions are imperative. One potential solution is the implementation of charging control mechanisms. This paper analyzes the impact of a residential charging station on a low voltage microgrid from the power quality point of view using a one-year operation simulation. Thirty-seven charging station scenarios with different locations within the network were examined, including instances with no charging control and various combinations involving charging control, photovoltaic power plant, and battery energy storage system. The simulation results of the charging station without charging control show a decrease in some power quality indicators, such as exceeding voltage change thresholds after charging station connection and increasing power losses. On the contrary, the scenarios implementing charging control and local resources effectively mitigate the adverse effects of charging stations on the microgrid.

The utilization of the electricity storage into batteries system is increasing. Most batteries are connected at the point in the network where the power of renewable energy sources is produced. These battery storage systems serve primarily to power electricity to households. They are most often used in cooperation with renewable energy sources, especially photovoltaic power plants. When installing renewable sources without using battery storage in distribution networks, there are several problems in the production of electricity from renewable sources. At a time of low power consumption and high electricity generation at the point of connection of renewable energy sources, a change in power flow occurs. The power generated from the sources flows into the distribution network or up to the superior network. If a distribution company installed battery storage at the point of connection, the power from renewable sources would not flow to the rest of the distribution system and would be stored on that distribution network node. Once the capacity size has been correctly determined at a given node, the distribution company could benefit from such solution. The distribution company could lease the capacity of the batteries to customers who have the renewable energy sources to store their produced energy or could cover part of the electricity consumption at the time of lack of production from the renewable energy sources. The paper deals with this issue, the location of battery storage is simulated on a standardized distribution network.

This article deals with the possibilities and technical implementation of a lighting retrofit in the common spaces of administrative buildings. These spaces are suitable for retrofit because they contain the same luminaires that can be upgraded. Also the measurements of electricity consumption before and after a retrofit were made to verify the retrofit results. According to the measured values, two kinds of retrofits with different degrees of intelligence were realized. The first is based on motion sensors. The second is based on the motion sensors and measurement the illuminance level to maximize the sunlight usage. The last part comprises the technical and economical conclusion of the implemented systems.

This document discusses about photovoltaic system which is based on an Arduino Mega 2560 microcontroller board. System has several functions, like measurement, controlling, user interface and external monitoring on PC with some another function, that are described in this paper. This system uses MPPT DC/DC converter, pure sine wave single phase inverter, measuring probes, switching relays and controller board with display.

This paper discusses about intelligent buildings and design of our own simple control system that will communicate with multiple actuators and sensors over Ethernet and to evaluate the measured values. The system consist of three devices based on Arduino Ethernet development boards and Quido ETH 4/4 board. This system can be used to control processes in intelligent buildings.

Today there are increasing efforts to decrease the power consumption of buildings. Even simple and inexpensive solutions can significantly influence the energy consumption. This paper describes the issue of power consumption of buildings. The main area of interest is focused on the lighting. The data, that are used to draft the concept of power consumption reduction, were obtained by measurement and simulations. Measures based on these data were taken in order to reduce the power consumption needed to achieve the required illuminence level and they were verified with measurements and simulations.