June 2026, Issue 6 (864)

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TABLE OF CONTENTS

Ryszard BARTNIK
A measure of the thermodynamic perfection of individual electricity generation technologies

 

POWER ENGINEERING AND LIGHTING TECHNOLOGY

Przemysław TABAKA
Is lighting designed for young people sufficient for an aging society?

 

Danuta MIEDZIŃSKA
Clean Geothermal Energy – Poland’s Potential and Global Perspectives

Marcin LASKOWSKI
Characteristics of the district heating sector in Poland

 

POWER ENGINEERING – SCIENCE – INDUSTRY

Bogumił DUDEK, Piotr KICIŃSKI, Robert KUBICKI, Wojciech LEŚNIAK
Switches in operation – the topic of the conference in Świeradów Zdrój

 

POLISH POWER ENGINEERS

Bogumił DUDEK
Edward Musiał (1937-2025). Honorary Member of the SEP

 

DILEMMAS, CONTROVERSIES

Bogumił DUDEK, Jerzy DĄBROWSKI
Direct current transmission – on the margins of the publication in Elektro.info

 

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SUMMARIES

 

Ryszard BARTNIK
A measure of the thermodynamic perfection of individual electricity generation technologies
This article analyzes the thermodynamic perfection of individual technologies for generating electricity, the most valuable form of energy. This perfection is measured by the exergy loss (power loss) per unit of heat from which this energy is produced.

 

Przemysław TABAKA
Is lighting designed for young people sufficient for an aging society?
The progressive aging of societies in developed countries is becoming a significant challenge, not only social and economic, but also technical. One area of technical infrastructure requiring adaptation to the changing age structure of the population is electric lighting. Significant physiological changes in the human eye occur with aging, particularly a decline in accommodation and adaptation abilities, a reduction in pupil diameter, and a reduction in the spectral transmittance of the eye lens. These phenomena significantly reduce visual performance in older adults under unchanged lighting conditions. This article presents the demographic determinants of aging societies in developed countries, discusses the basic physiological mechanisms responsible for the deterioration of visual perception with age, and analyzes the implications of these phenomena for the design of electric lighting systems in interiors.

 

Danuta MIEDZIŃSKA
Clean Geothermal Energy – Poland’s Potential and Global Perspectives
The article discusses the issue of acquiring clean energy from the depths of the Earth from specific petrothermal formations, referred to as Hot Dry Rock (HDR) or Enhanced/Engineered Geothermal Systems (EGS). In the face of depleting conventional fossil resources and barriers related to nuclear energy and weather-dependent renewable energy sources, HDR/EGS technology represents a stable, climate-independent energy alternative. The paper presents an analysis of global geothermal potential, describes the general technological assumptions of HDR systems operation along with implementation examples, and summarizes key patent solutions in this field. Special attention is paid to the geological conditions and petrothermal potential of Poland, indicating key thermal anomaly areas (so-called Hot Spots) qualifying for future research and development work.

 

Marcin LASKOWSKI
Characteristics of the district heating sector in Poland
The district heating sector in Poland is a key pillar of the national energy system, supplying heat to millions of residents and supporting energy security. It is characterized by a decentralized structure, with numerous local systems and a strong dominance of corporatized entities, often linked to municipal ownership. Despite significant infrastructure capacity, the sector remains fragmented, which limits its investment potential. Currently, the sector is undergoing a major transformation, gradually reducing its reliance on coal in favor of gas and renewable energy sources, with cogeneration playing an important role. Key challenges include increasing regulatory pressure, declining heat demand, and the need for substantial investment. In the long term, the sector’s development will depend on decarbonization, integration with the power system, and the adoption of modern technologies such as heat storage and Power-to-Heat solutions.