Wojciech Stanek

Silesian University of Technology

The use of solar radiation energy is one of the important elements to achieve energy transformation. This potential can be utilized by generating electricity with PV modules or heat from collectors. It is also possible to combine these elements into one system and more efficient use of solar radiation, as is the case with the Photovoltaic thermal c...

The article presents problems related to the assessment of local energy efficiency of energy systems. In practice, local energy efficiency is commonly used to evaluate these systems, which is not a correct criterion to compare different energy technologies, especially non-renewable and renewable energy systems. For the correct assessment of efficie...

Wind as a renewable energy source is characterized by rapid growth of installed power in many countries, including Poland, where its share in the electricity production has grown over 25 times in the last decade, now reaching about 10%. Since renewable energy has priority in access to the grid, it forces the dispatchable coal-fired power plants to...

This article concerns natural gas liquefaction using high-pressure potential, which is available in pressure letdown stations. The article proposes an integration of a pressure letdown station with a natural gas liquefaction line which enables partial exergy recovery and decreasing natural resources consumption to produce LNG. Exergy recovery is ca...

Captured CO2 from large industrial emitters may be used for enhanced oil recovery (EOR), but as of yet there are no European large-scale EOR systems. Recent implementation decisions for a Norwegian carbon capture and storage demonstration will result in the establishment of a central CO2 hub on the west-coast of Norway and storage on the Norwegian...

The paper presents a thermo-ecological analysis of a liquefied natural gas regasification system equipped with a Stirling engine. The proposed system includes an alpha configuration machine, working as a cold engine with the heat sink acting as the evaporator for the LNG and the upper heat source being at ambient temperature (sea water) or moderate...

The paper presents a Computational Fluid Dynamics (CFD) model of the cold alpha-type Stirling engine. The developed mathematical model comprises of Unsteady Reynolds Averaged Navier-Stokes (URANS) set of equations, i.e. continuity, momentum and energy equations. Moreover, the developed mathematical model comprises a non-equilibrium description of t...

The deployment of wind power is rapidly growing worldwide. Intermittent, unpredictable availability of wind energy destabilizes the work of the whole power system, which causes additional consumption of resources. When fossil fuel power plants are affected by this phenomenon, they are forced to cycle (change their load) more often, which results in...

Evaluation of thermodynamic efficiency of a power plant is usually performed using the method of so-called thermal diagnostics, based on energy balancing. Energetic analysis is however suitable only for a quantitative assessment and for comparing similar technologies. In order to properly assess the origins of energy losses in the given system, an...

Professor Jan Szargut was one of the world pioneer of exergy analysis and his adventure with exergy going back to its beginnings in world science. His subsequent and significant contribution to the field of exergy analysis is certainly not to be overestimated. Within the paper a short overview of Professor Szargut activity is presented. One of the...

Wind power is one of the most popular renewable energy sources (RES), characterized by rapid growth of installed power in the energy mix of many countries. Usually, the influence of wind technologies on the depletion of nonrenewable resources is evaluated taking into account the consumption of energy and materials in the construction phase. However...

An increased wind capacity penetration reduces loading on conventional thermal units causing higher fuel requirements due to the off-design operation. Regarding the environmental analysis, such an adverse effect should be allocated to the operational phase of wind turbines. In the present work, we apply Thermo-ecological Cost (TEC) to evaluate the...

Heat pumps (HP) represent an attractive option as a heat source, since they utilise “free” ambient heat. However, as they need to be driven by electric energy, their ecological efficiency depends not only on their performance, but also on the energy mix used for electricity generation. Effectiveness of HP can be improved by applying renewable energ...

In this paper, we apply a life cycle thermoecological cost (LC-TEC) approach to evaluate the environmental performance of wind turbines with different capacities and performance characteristics. LC-TEC expresses the cumulative consumption of non-renewable exergy burdening the fabrication of the considered consumption of the product with the additio...

Hybridization of Waste to Energy (WtE) plants with solar facilities can take competing energy technologies and make them complementary. However, realizing the benefits of the solar integration requires careful consideration of its efficiency. To analyse such systems from the point of view of resource efficiency, the pure energy analysis is not suff...

Nuclear energy is one of the possibilities ensuring energy security, environmental protection, and high energy efficiency. Among many newest solutions, special attention is paid to the medium size high-temperature gas-cooled reactors (HTGR) with wide possible applications in electric energy production and district heating systems. Actual progress c...

This study investigated the environmental benefits of a new boiler design for a fossil fuel-based power plant with CO2 capture, utilisation, and storage (CCUS) through thermo-ecological cost (TEC) analysis. MILD oxy-fuel combustion (MOFC) combines the advantages of the moderate and intense low-oxygen dilution (MILD) combustion and oxy-fuel combusti...

In the paper, a second order thermodynamic analysis of a small scale alpha-type Stirling engine is presented. The developed mathematical model is based on the Finite Time Thermodynamics (FFT) approach and it is derived from the differential time dependent equations of energy and mass conservation. The engine model consists of three spaces: compress...

This paper presents the computational fluid dynamics (CFD) model of small-scale α-type Stirling engine. The developed mathematical model comprises of unsteady Reynolds averaged Navier–Stokes set of equations, i.e., continuity, momentum, and energy equations; turbulence was modeled using standard κ–ω model. Moreover, presented numerical model covers...

Nowadays, the society faces the challenge of continuous supply of electricity. Energy from two different sources of origin such as renewable and non-renewable is used to meet the needs of modern humankind. The paper presents the findings concerning the thermo-ecological cost assessment of renewable energy sources defining their total impact on the...

The paper presents the advantages of a new boiler solution for the supercritical power plant with CO2 capture. The mild oxyfuel combustion (MOFC) combines the advantages of mild (moderate and intensive low-oxygen dilution) combustion and oxyfuel combustion for the purpose of an effective CO2 capture from fossil fuel based power generation. MOFC app...

The concept of the pro-ecological tax or support is proposed in this article. It could replace the existing subsidy mechanisms for renewable power technology or could represent the ecological taxes burdening the fabrication of consumer products based on nonrenewable resources, e.g., electricity from the conventional fossil fuel power plants. Moreov...

The biogas fired tri-generation system for cooling, heating and electricity generation (BCCHP + PV) supported by a photovoltaic system (PV) is discussed and analyzed from energetic and ecological effectiveness point of view. Analyzed system is based on the internal combustion engine and the adsorption machine. For the evaluation of primary energy s...

The multi-criteria analysis of different power technologies takes into account TEC (thermo-ecological cost); direct and cumulative emissions; and economic evaluation. The environmental and ecological comparison of the planned nuclear power plant with the existing conventional ones (coal and gas plants) requires the evaluation of the whole life cycl...

The use of coal is suspected to have high environmental impact. Natural gas is treated as more environmentally friendly with high methane content and lower emission factors. In order to calculate the environmental impact in the whole life cycle associated with combustion of coal and natural gas all stages from “cradle to grave” should be taken into...

The paper presents a comparison of selected power technologies from the point of view of emissions of greenhouse gases. Such evaluation is most often based only on analysis of direct emissions from combustion. However, the direct analysis does not show full picture of the problem as significant emissions of GHG appear also in the process of mining...

LNG (liquefied natural gas) delivered by means of sea-ships is pressurized and then regasified before its introduction to the system of pipelines. The utilization of cryogenic exergy of LNG for electricity production without combustion of any its portion is analyzed. For the conversion of LNG cryogenic exergy into electricity, the Stirling engine i...

Polish energy sector is mainly based on coal combustion, which is responsible for increasing the CO2 emission. Simultaneously, European trends toward sustainability and global warming mitigation will lead to significant changes in the structure of electricity generation in Poland. Due to the domestic energy policy the increase of renewable resource...

Fossil fuels are still the dominant source of energy in most economic sectors worldwide, particularly in the electric power sector. The transformation and usage of primary energy are connected with various unfavorable environmental effects. Mainly they are as follows depletion of constrained resources of non-renewable energy, emission of harmful wa...

Thermo-ecological cost with the inclusion of life cycle (TEC-LC) is defined as the cumulative exergy consumption of non-renewable natural resources associated with any product and its life cycle, taking into account the necessity to prevent and compensate losses caused by depletion of natural resources and the release of harmful substances into the...

The paper presents a thermoecological evaluation of a trigeneration module based on an Internal Combustion Engine fuelled with selected fuels of various origin: domestic/mixed-origin natural gas, CMM (coal mine methane) and biogas. The generated products comprise: electric energy, heat available in hot water and cold generated in an absorption chil...

The current energy policy requires a constant technology development towards more sustainable energy transformation systems. Cogeneration and the use of renewables are two important solutions available to achieve this goal. If cogeneration is applied locally, e.g. as CHP (combined heat-and-power generation) modules with internal combustion engines,...

Biomass integrated gasification cogeneration is nowadays considered as one of the most attractive technologies for CO2 emission reduction and non-renewable fuel savings. The paper presents application of the Thermo-Ecological Cost (TEC), which expresses the cumulative consumption of non-renewable exergy, for examination of energy and environmental...

In this paper, an exergy analysis of nickel processing is performed through the application of two methodologies: TEC (thermo-ecological cost) and ERC (exergy replacement cost). The merging of both methodologies allows to have a complete assessment of non-fuel mineral processing. TEC evaluates the cumulative consumption of non-renewable exergy requ...

Technological processes in food industry require chilling agent. System of chillers can be driven by non-renewable or renewable sources. In the group of renewable sources solar collectors seem to be an attractive solution both as the basic or the auxiliary power source for adsorption refrigerators. The common tool for the evaluation of the refriger...

The paper presents a novel concept for thermodynamic evaluation of a selected energy system. The presented method has been developed by integration of the Thermo-Economic Analysis with the theory of Thermo-Ecological Cost. It can be applied as a thermodynamic evaluation method of rational resources management within any production system. It takes...

Thermodynamic optimization of thermal devices requires information about the influence of operational and structural parameters on its behaviour. The interconnections among parameters can be estimated by tools such as CFD, experimental statistic of the deviceetc. Despite precise and comprehensive results obtained by CFD, the time of computations is...

Biomass is a renewable feedstock for producing modern energy carriers. However, the usage of biomass is accompanied by possible drawbacks, mainly due to limitation of land and water, and competition with food production. In this paper, the analysis concerns so-called second generation biofuels, like Fischer-Tropsch fuels or Substitute Natural Gas w...

The thermoecological cost, expressing the cumulative consumption of nonrenewable exergy per unit of the considered useful product, may be divided into the fuel part and the mineral part. The fuel part may be eliminated by the utilization of renewable exergy carriers. The mineral part cannot be eliminated. The depletion of mineral resources leads to...

Economic activities generate pollution, which causes damages to the society and the environment. It is possible to estimate the quantities of emitted pollutants from energy conversion systems using thermodynamic principles combined with empirical techniques. The indices of direct emission are often not sufficient to show the entire environmental lo...

The energy diagnosis of power plants and combined heat-and-power plants (CHP) is a very important form in the point of view of rational management of primary energy resources as well as from the economical point of view. The most irreversible component of a power plant is the boiler and the most important factor influencing the energy efficiency is...

The energy diagnosis of power plants and combined heat-and-power plants (CHP) is a very important form from the point of view of rational management of primary energy as well as from the economical and ecological point of view. The control procedures can be based on measurements or on simulations with application of mathematical models. The Authors...

All production processes generate pollution and cause damages to the environment as well as the society. Investigation of the influence of operational parameters of energy systems on formation of cost of pollutants requires the application of emissions modeling. Due to the fact that modeling based on physical phenomenon is very complicated and requ...

The thermo-climatic cost (TCC) expresses the cumulative emission of CO2 burdening all the steps of production processes connected with the fabrication of particular consumption products. The TCC of the considered product results from the consumption of semi-finished products and energy carriers. The TCC of hydrocarbon fuels contains three component...

The paper presents the possibility of integration of the Corex process, blast furnace, CO2 removal installation and metallurgical combined heat and power (CHP) plant. Such an integration has significant advantages from the technical and environmental points of view. As the Corex export gas (after CO2 removal) is a highly valuable reducing agent, it...

In the case of big energy boilers energy efficiency is usually determined with the application of the indirect method. Flue gas losses and unburnt combustible losses have a significant influence on the boiler's efficiency. To estimate these losses the knowledge of the operating parameters influence on the flue gases temperature and the content of c...

The proposed pro-ecological tax should be proportional to the cumulative consumption of non-renewable natural exergy burdening the considered product. It should replace the existing value-added tax (VAT). The income of the state after introducing the new tax, should remain without any change. That principle determines the coefficient of proportiona...

The optimization of operational parameters in control systems requires the application of a mathematical model of the investigated process. Analytical models are usually complicated and time-consuming. For optimization purposes more convenient are empirical models which express the main characteristic of the behaviour of the investigated process. O...

The paper presents a method and example results of calculations of the neural modelling of steam boilers. Empirical models can be worked out based on the results of specially organised measurements or continuous measurements recorded in the computer system storing the operational performance. The introduction of operational measurement data for mat...

The depletion of non-renewable natural exergy resources (the thermo-ecological cost) has been accepted as the objective function for thermo-ecological optimization. Its general formulation has been cited. A detailed form of the objective function has been formulated for a solar collector producing hot water for household needs. The following design...

The technology ‘blast furnace—converter’ dominates at present in the production of steel all over the world. Therefore, the blast-furnace process is continuously being improved, among others, by raising the thermal parameters, such as temperature and oxygen-enrichment of the blast, as well as the addition of auxiliary fuels. The changes in the cons...

The blast-furnace process dominating in the production of steel all over the world is still continuously improved due to its effectiveness (exergy efficiency is about 70%). The thermal improvement consist in an increase of the temperature of the blast and its oxygen enrichment, as well as the injection of cheaper auxiliary fuels. The main aim is to...

The determination of the natural capital exergy is linked to the definition and thermodynamic properties of the Reference Environment (R.E.) used. Hence the importance of an appropriate selection of the R.E. The aim of this paper is to obtain and propose in ECOS 2005, an agreement on the legal international reference environment for evaluating the...

The application of theoretical empirical mathematical model the of blast furnace and energy characteristics of a Cowper stove to identify the influence of working parameters upon the supply and net calorific value of blast furnace-gas has been discussed. Results of exemplary calculations have also been presented.

The cumulative consumption of non-renewable exergy connected with the fabrication of particular products has been termed as their ecological cost. System of linear input–output equations determining the ecological costs has been formulated. The cogeneration processes have been considered using the principle of the avoided costs of fabrication of th...

Biomass integrated gasification combined cycle cogeneration is nowadays considered as one of the most attractive technology for CO 2 emission reduction and non-renewable fuel savings. Different criterions such as primary energy savings or emission reduction are usually taken into account in order to evaluate potential energy and environmental benef...