Until the early 1990s, the domestic power industry was a natural monopoly. This was caused by the specificity of the operation of the electricity transmission and distribution sub sectors, technical challenges of coordinating the operation of generating units and transmission networks, requirements regarding long-term forecasting of the industry development, and returns to scale. In view of the above, the objective of the presented paper is to assess the economic situation of energy companies operating in a competitive electricity market. The article analyses the main areas of activity of the energy companies, i.e.: the areas of production, transmission, distribution, and sales. In addition, the market shares of the various energy companies, in terms of generating capacity and the amount of the energy produced, were analyzed. Furthermore, the technical and economic situation of enterprises operating in the power sector was also subjected to analysis. The mentioned analysis has revealed that the profit received from the main activity of the enterprises (i.e. the sale of electricity) has decreased in recent years. What is more, the energy sector must adapt to legal and regulatory changes related to the intensification of the decarbonization policy pursued by the European Commission. Therefore, national energy should focus on developing skills in the areas of innovation, such as: electro mobility, energy storage, energy management, etc.

The paper presents a thermal-economic analysis of a 900 MW coal-fired power unit for ultra-supercritical parameters with internal steam reheat. The subject of the study was the cycle proposed as the "initial thermal cycle structure" during the completion of the project "Advanced Technologies for Energy Generation" with the steam parameters of 650/670 °C/30 MPa. Two configurations of internal reheat were analysed: with a four- and seven-section exchanger. The effect of reheat on the operation of the power unit under a partial load was also analysed, and preliminary calculations of the heat exchange area of the internal reheat were made.

This article describes a thermodynamic analysis of an oxy type power plant. The analyzed power plant consists of: 1) steam turbine for supercritical steam parameters of 600 °C/29 MPa with a capacity of 600 MW; 2) circulating fluidized bed boiler, in which brown coal with high moisture content (42.5%) is burned in the atmosphere enriched in oxygen; 3) air separation unit (ASU); 4) CO2 capture installation, where flue gases obtained in the combustion process are compressed to the pressure of 150 MPa. The circulated fluidized bed (CFB) boiler is integrated with a fuel dryer and a cryogenic air separation unit. Waste nitrogen from ASU is heated in the boiler, and then is used as a coal drying medium. In this study, the thermal efficiency of the boiler, steam cycle thermal efficiency and power demand were determined. These quantities made possible to determine the net efficiency of the test power plant.

The paper looks at an analysis of the tendency of changes in the fuel structure of electricity

generation and thus resulting changes in carbon dioxide emissions. Forecasts drawn up by various

institutions and organizations were selected for the analysis. Firstly, on the basis of statistical data

contained in (IEA 2017a, IEA 2008) and with the use of Kay’s indicators, the impact of changes in

energy intensity of the national income and energy mix on changes in carbon dioxide emissions per

capita in 2006–2015 for the OECD countries and Poland were analyzed. A small effect of changes

was found in the fuel mix in this period of time on the emissions. The main impact was due to changes

in the energy intensity of the national income and changes in the national income per capita.

Next, selected fuel scenarios for the period up to 2050 (60) were discussed – WEC, IEA, EIA, BP,

Shell, with a focus on the WEC scenarios. These have been developed for various assumptions with

regard to the pace of economic development, population growth, and developments of the political

situation and the situation on the fuel market. For this reason, it is difficult to assess the reliability

thereof. The subject of the discussion was mainly the data on the fuel structure of electricity generation

and energy intensity of national income and changes in carbon dioxide emissions. The final

part of the paper offers a general analysis of forecasts drawn up for Poland. These are quite diverse,

with some of them being developed as part of drawing up the Energy Policy for Poland until 2050,

and some covering the period up to 2035. An observation has been made that some forecasts render

results similar to those characteristic of the WEC Hard Rock scenario.

The progressive processes of globalization and changes in the global, European and local economy require integrated efforts aimed at solving problems related to development at the national regional and the local level involving the environment, energy sources, climate and technological transformation issues. European Union Member States are given right to create an individual Energy mix. Coal will continue to play a major role in Poland’s energy mix during the next decades. Polish coal reserves can provide energy security for decades.

Despite crude oil and natural gas growth in fuel consumption, coal will continue to be the stabilizer of energy security for the country and play an important role in Poland’s energy mix in the years to come. However, further coal consumption requires investments in low carbon technologies which are of high efficiency and in high-efficiency cogeneration.

The validity of the full utilization of cogeneration potential should be highlighted. Operating cogeneration plants are more expensive than power plants but they are more efficient and generate less carbon emissions. In accordance with the assumptions of the Energy policy of Poland, a low-carbon economy with renewable Energy sources and nuclear Energy should be supported and developed, however the obsolete coal generators should be replaced with low-carbon high-efficient ones.

(1) Jak pokazują powszechnie akceptowane i świetnie udokumentowane wyniki badań naukowych, ludzkość, chcąc uniknąć najbardziej dramatycznych skutków antropogenicznego ocieplenia klimatu, musi radykalnie obniżyć, w perspektywie 10-letniej o połowę, a docelowo do 2050 roku do zera, emisję gazów cieplarnianych. To zadanie stoi też przed Polską i wynika zarówno z odpowiedzialności za przyszłość następnych pokoleń Polaków i naszej cywilizacji, jak i konieczności wypełnienia zobowiązań międzynarodowych.
(2) Dekarbonizacja gospodarki dotyczyć musi wszystkich gałęzi gospodarki. W Polsce najpilniejszym zadaniem jest szybka dekarbonizacja produkcji energii elektrycznej, gdyż z powodu dominującej roli węgla największy, bo 45-procentowy udział w emisji gazów cieplarnianych ma sektor energetyczny (średnio w Unii Europejskiej 29%). Transformacja przemysłu energoelektrycznego musi uwzględniać jednak bezpieczeństwo energetyczne kraju i obywateli. Konieczność szybkiego odchodzenia od paliw kopalnych w sektorze energetycznym wynika nie tylko z dbałości o klimat, ale także z przesłanek ekonomicznych (ceny hurtowe energii elektrycznej w Polsce należą do najwyższych) oraz technicznych (znaczna część energetyki węglowej dobiega kresu możliwości eksploatacyjnych). Dekarbonizacja sektora energetycznego musi następować w tempie większym, niż sugeruje to rządowy dokument PEP2040, który zakłada niezrozumiałe ograniczenia dotyczące szybkiego rozwoju energetyki wiatrowej na lądzie i fotowoltaiki. Niezbędna jest też intensyfikacja działań zwiększających oszczędność energii.
(3) Transformacja energetyczna w Polsce powinna uwzględniać wszystkie nieemisyjne źródła energii, zarówno OZE, jak i energetykę jądrową. Ponieważ energetyka jądrowa dostarczy energii nie wcześniej niż za kilkanaście lat i pokryje tylko część rosnącego zapotrzebowania na energię elektryczną, natychmiast należy przyspieszyć budowę farm wiatrowych na morzu, a także odblokować i wesprzeć rozwój najtańszego obecnie źródła energii ! energetyki wiatrowej na lądzie. Fotowoltaika rozwija się bardzo szybko i jej aktualne wsparcie wydaje się wystarczające. Należy jednak wprowadzić przepisy, które umożliwiłyby mieszkańcom wielorodzinnych budynków i osiedli udział w produkcji energii jako zbiorowych prosumentów, aby w jak najszerszym zakresie włączyć kapitał obywatelski w proces transformacji energetycznej.
(4) Ponieważ produkcja energii elektrycznej z wiatru i słońca ma zmienny charakter, równolegle do wzrostu mocy tych źródeł niezbędne jest inwestowanie w szczytowe/ bilansujące źródła energii i jej magazynowanie, a także możliwość zagospodarowania nadwyżek wyprodukowanej energii. Wśród źródeł szczytowych/bilansujących należy wymienić szczytowe elektrownie gazowe (z możliwością współspalania wodoru), magazyny bateryjne, a także możliwość utrzymania części najnowszych elektrowni węglowych jako rezerwy w wypadku długich niedoborów energii z OZE. W ramach zagospodarowywania nadwyżek energii z OZE system energetyczny powinien być stopniowo wyposażany w elektrolizery do produkcji wodoru, możliwego potem do wykorzystania jako paliwo. Ze względu na okresowość działania, a jednocześnie ważną rolę w bezpieczeństwie energetycznym te elementy systemu energetycznego mogą być nierentowne, dlatego inwestycje w nie, a następnie utrzymanie, muszą mieć wsparcie finansowe wliczane do kosztów systemowych.
(5) Kluczowe znaczenie będzie miała modernizacja i rozbudowa sieci przesyłowych, w tym przystosowanie ich do zwiększającego się rozproszenia źródeł energii elektrycznej. Powinien to być jeden z priorytetów transformacji energetycznej i koszty tych działań także powinny zostać uwzględnione w kosztach systemowych.
(6) W polskich warunkach środowiskowych (brak możliwości istotnego rozwoju energetyki wodnej i geotermii, niskie usłonecznienie w chłodnej porze roku i długie okresy bezwietrzne na znacznej części kontynentu europejskiego) istotną rolę w domknięciu dekarbonizacji odegrać powinna energetyka jądrowa. Konieczne są więc systematyczne prace ponad podziałami politycznymi nad jej bezpiecznym rozwojem i budowa społecznego poparcia dla tego rozwiązania.
(7) Szybka transformacja energetyczna jest szansą na włączenie w proces generowania energii nowych podmiotów i grup społecznych oraz na zrównoważony rozwój lokalny. Jednocześnie będzie ona powodowała wiele napięć społecznych, szczególnie w sektorach i regionach zależnych od energetyki opartej na węglu i górnictwie, a także może skutkować ubóstwem energetycznym wśród niektórych grup społecznych. Ważnym elementem transformacji powinna być odpowiednia polityka zachęcająca do wykorzystania lokalnych szans rozwojowych i łagodząca niepożądane skutki społeczne.

This paper presents the results of modeling and analysis of hybrid generation system (HSW). The system contains municipal waste gasification installation, photovoltaic (PV) system and wind farm. The system cooperates with the power system to provide electrical energy to the communal consumer. The consumer is characterized by a maximum power demand equal to 10 MW and an annual energy demand of 42.351 GWh. Generation with renewable sources was modelled using meteorological data. Moreover, in order to cover the demand with the level of generation, gas storage was used. Next, the three-stage gasification model is presented. It was validated, using the literature data, and its efficiency and gas composition have been calculated and are presented. Furthermore, energetic and economic analysis have been conducted. Installed power usage factor and efficiency of energy sources were calculated. Gross and net energy generation of hybrid generation systems have been computed and are presented. In this analysis, energy consumption by gas compressing was included. The analyzed HSW covered 54.5% of the demand. Most of this (30.2%) was covered by the gasification system. However, the system was characterized by a low net efficiency equal to 16.7%. Diagrams of power generation in each source and storage fill chart are presented. In the economic part of the analysis, results of calculations of net present value and payback period are published in order to examine the profitability of the system.
The cost of electricity was 490–1050 PLN/MWh. The results show that municipal waste gasification can be used as a part of HSW to adjust the generation with the demand. Moreover, it can be economically advantageous. However, it is characterized by high CO ₂ emission and low efficiency of the waste processing system.

The article assesses the production capacity of the Polish Power System, taking into account the military operations in Ukraine and the related resource crisis. An analysis was made of how the war in Ukraine will affect the validity of Poland’s energy policy adopted a year ago. The sensitivity of the Polish Energy System to the import of energy resources from Russia was assessed as well as the possibilities of filling the gap caused by the lack of these raw materials were described and measures were proposed. It shows how electricity prices in the EU countries developed in the last year and what the energy mix of these countries looked like. Alternative scenarios for the transformation of the domestic system were discussed, including the coal – renewable energy – nuclear energy scenario, with the minimization of gas as a fuel of the transition period.

The paper presents a brief outline of the European Union Climate and Energy Package in early 2020, as well as the EU’s plans in this respect until 2030 (Winter Package and Green Deal) and even further until 2050 (EU’s climate neutral target). Also the current condition of power generation in Poland and challenges for Polish energy sector in the nearest future are discussed. The Energy Policy of Poland until 2040 (EPP 2040) is analysed in relation to possible risks and dangers. Some improvements are proposed in regard to the implementation of the document. In addition, the current volume and perspectives of hard coal and lignite mining in Poland until 2040 are discussed and compared with an expected demand for coal in Polish power plants and combined heat and power stations. On the basis of the prognosis of energy consumption in the period 2031-2040, there seems to appear a serious risk of energy shortage due to a possible delay in a nuclear power project and lack of lignite mining at the level defined in EPP 2040 policy. Therefore, some variants of providing the security of energy supplies are taken into account and thoroughly analysed in the paper.

The constructed wetland integrated with microbial fuel cell (CW-MFC) has gained attention in wastewater treatment and electricity generation owing to its electricity generation and xenobiotic removal efficiencies. This study aims to use the CW-MFC with different macrophytes for domestic wastewater treatment and simultaneously electricity generation without chemical addition. The various macrophytes such as Crinum asiaticum, Canna indica, Hanguana malayana, Philodendron erubescens, and Dieffenbachia seguine were used as a cathodic biocatalyst. The electrochemical properties such as half-cell potential and power density were determined. For wastewater treatment, the chemical oxygen demand (COD) and other chemical compositions were measured. The results of electrochemical properties showed that the maximal half-cell potential was achieved from the macrophyte D. seguine. While the maximal power output of 5.42±0.17 mW/m2 (7.75±0.24 mW/m3) was gained from the CW-MFC with D. seguine cathode. Moreover, this CW-MFC was able to remove COD, ammonia, nitrate, nitrite, and phosphate of 94.00±0.05%, 64.31±0.20%, 50.02±0.10%, 48.00±0.30%, and 42.05±0.10% respectively. This study gained new knowledge about using CW-MFC planted with the macrophyte D. seguine for domestic wastewater treatment and generation of electrical power as a by-product without xenobiotic discharge.

This paper discusses the impact of the European Green Deal policy on the clean energy transformation in the European Union, focusing on the generation of electricity reaching a significant milestone for the EU in 2020 – renewable energy sources for the first time in history surpassing combined fossil fuels in the generation of electrical energy. This achievement, although partially influenced by the exceptional circumstances of the COVID-19 pandemic and the electricity demand shock, is primarily an effect of the Clean Energy for all Europeans Package implementing the European Green Deal strategy designed to position the EU as a global leader in the green transformation, leading by example and turning climate challenges into a growth opportunity, and in doing so presenting an optimistic policy perspective for a global transformation towards a 100% renewable energy world, thus supporting mitigation of the global-warming threats by significantly cutting greenhouse-gas emissions. With the immediate effects of the 2018 recast Renewable Energy Directive (2018/2001/EU) and other related clean-energy policies under the umbrella of the European Green Deal, coal and lignite electric generation has fallen in 2020 by as much as 22% (87 TWh) and the nuclear generation has dropped by 11% (79 TWh), with natural gas to a much lesser extent, yet still noting an annual drop of 3%, while renewables grew, surpassing the combined fossil fuels electricity output in the whole of the EU. This is an impressive result confirmed in late 2021 and a hallmark of the European Green Deal initial success, the sustainability of which is yet to be assessed in the coming years, especially in view of the recent international situation of major destabilization. In this context, it should be added that although the newest 2022 Global Energy Review report by the IEA confirmed in 2021, the highest global CO ₂emission level in history (following the post -pandemic economic rebound and also due to the gas-price crisis of late 2021 causing gas-to-coal shifts in electricity-mix, which in the EU, resulted in a 7% relative annual emissions increase), Europe’s emission level has remained in a diminishing trend following the European achievements of 2020, with an overall CO ₂ emissions decrease of 2.4% in comparison with the level of 2019. Most likely, however, the 2021 gas-price crisis was only a mere prelude to a much more robust long- -term perturbation that will be expectedly due to the war in Ukraine and the necessary sanctions policy, especially impacting the energy market and probably further hampering the green-transition process jointly with other economic factors.

This article presents an analysis of the sustainable development of generation sources in the Polish National Electric Power System (NEPS). First, the criteria for this development were formulated. The paper also discusses the current status of generation sources, operating in power plants and combined heat and power (CHP) plants of NEPS. Furthermore, it includes a prediction of power balance in NEPS, determining; predicted electricity gross use, predicted demand for peak capacity during the winter peak, predicted demand for peak capacity during the summer peak and required new capacity of centrally dispatched generation units (CDGUs) in 2025, 2030, 2035 and 2040 that would ensure NEPS operational security. Twenty prospective technologies of electricity generation and combined electricity and heat production were analyzed. These were divided into three groups: system power plants, high- and medium-capacity combined heat and power (CHP) plants, as well as small-capacity power plants and CHP plants (dispersed sources). The unit costs of electricity generation discounted for 2021 were calculated for the analyzed technologies, taking the costs of CO2 emission allowances into account. These costs include: capital costs, fuel costs, maintenance costs, operation costs and environmental costs (CO2 emission allowances). This proceeds to a proposal of a program of the sustainable development of generation sources in NEPS, which includes the desired capacity structure of power plants and CHP plants, and the optimal structure of electricity production in 2030 and 2040. The results of calculations and analyses are presented in tables and figure.