Dominant Share Research Articles

Economic Analysis of the Operation of a Hydropower Plant in a Wastewater Treatment Plant: Toruń, Poland

The energy industry is constantly changing and evolving. One of the visible solutions is the pursuit of low-emission solutions. One such solution is investment in renewable energy sources (RESs), including hydropower, which in 2023 will constitute a dominant share in the production of electricity from RESs (47.02%) in the world. One of the alternative solutions is the use of hydropower in wastewater treatment plants, whose global potential is estimated at about 4350 TWh. An important issue in the operation of these facilities is their profitability. This article presents an economic analysis of a hydropower plant in the wastewater treatment plant in Toruń (northern Poland) in order to assess its profitability in the context of profits, costs, and payback period. The analyses showed the profitability of 9 out of 12 characterized variants, with the payback period estimated for real variants at 10.75–23.74 years and for theoretical variants at 5.06–5.32 years. The most significant factor in reducing the payback period was the level of electricity production between years, while different types of settlements and changes in electricity sales prices played a lesser role. Taking into account all profitable variants, after 25 years of operation, the net income will amount to PLN 1.07 million for the actual variants and PLN 3.18 million for the theoretical variants. The work can contribute to understanding the specifics of the operation of such facilities, which is consistent with, among others, the goals of sustainable development, climate and energy policies, or the circular economy.

The Cosmic Ultraviolet Baryon Survey (CUBS). IX. The Enriched Circumgalactic and Intergalactic Medium Around Star-forming Field Dwarf Galaxies Traced by O vi Absorption

The shallow potential wells of star-forming dwarf galaxies make their surrounding circumgalactic and intergalactic medium (CGM/IGM) sensitive laboratories for studying the inflows and outflows thought to regulate galaxy evolution. We present new absorption-line measurements in quasar sight lines, probing within projected distances of <300 kpc from 91 star-forming field dwarf galaxies with a median stellar mass of logM⋆/M⊙≈8.3 at 0.077 < z < 0.73, from the Cosmic Ultraviolet Baryon Survey (CUBS). In this redshift range, the CUBS quasar spectra cover a suite of transitions including H i, low, and intermediate metal ions (e.g., C ii, Si ii, C iii, and Si iii), and highly ionized O vi. This CUBS-Dwarfs survey enables constraints with samples nine times larger than past dwarf CGM/IGM studies with similar ionic coverage. We find that low and intermediate ionization metal absorption is rare around dwarf galaxies, consistent with previous surveys of local dwarfs. In contrast, highly ionized O vi is commonly observed in sight lines that pass within the virial radius of a dwarf, and O vi detection rates are nonnegligible at projected distances of 1−2× the virial radius. Based on these measurements, we estimate that the O vi-bearing phase of the CGM/IGM accounts for a dominant share of the metal budget of dwarf galaxies. The absorption kinematics suggest that a relatively modest fraction of the O vi-bearing gas is formally unbound. Together, these results imply that low-mass systems at z ≲ 1 effectively retain a substantial fraction of their metals within the nearby CGM and IGM.

CURRENT ISSUES OF IMPORT OF MEDICAL DEVICES AND EQUIPMENT TO THE RUSSIAN FEDERATION

The import of medical products remains an important topic at present, given the relevance of healthcare in connection with the sanctions policy of Western countries and the ambiguous situation with foreign supplies of medical products. The situation with the dominant share of imported medical products in the Russian market highlights the dependence on international supplies and technologies in the healthcare sector. The policies and sanctions imposed by the European Union and other countries regarding the supply of medical equipment to Russia cause certain restrictions and difficulties due to the current political situation. Although these goods are classified as vital and do not fall under sanctions, many companies from Europe and the United States have suspended deliveries due to the so-called «moral embargo». Lack of access to modern equipment and medicines can lead to a deterioration in the quality of medical care, an increase in waiting times for treatment, as well as possible complications and a deterioration in the prognosis of the disease in patients. The article analyzes the dynamics of the medical products market over the past few years, and identifies changes in the structure of the medical devices market. The share in the import of medical equipment to Russia was also studied. In addition, the prospects for the development of the medical industry are considered and the current situation is assessed. To solve the problem in the short term, the necessary measures have been proposed to include vital medical devices and equipment in the list of the Ministry of Industry and Trade for its import according to the rules of parallel import.

Analysis of the Influence of Electricity Generation Mix on CO2 Emissions from Electric Vehicles in Europe

The rise in population mobility, with the dominant modal share of passenger vehicles, is particularly concerning due to its negative impact on the environment. Environmental issues caused by internal combustion engine (ICE) vehicles are increasing, as evidenced by the fact that road transport is responsible for 22% of total CO2 emissions. In this context, although electric cars do not emit harmful substances directly, power plants that generate electricity from various sources contribute significantly to these emissions. To determine the impact of electric vehicles on the environment, this study conducted a comparative analysis of gCO2/km emissions depending on the type of vehicle engine (petrol, diesel, and electric) across different European countries, based on their electricity sources. For more representative results, the comparison was made using the same make and model of car-Volkswagen e-Golf (electric car) and Golf 7 with diesel and petrol ICE engines. The results indicate that in Serbia, electric vehicles emit slightly less CO2 compared to diesel and petrol vehicles of similar characteristics. However, the difference is very small compared to diesel engines, amounting to only 3 gCO2/km.

Screening for Suitable Melatonin Application Scheme to Modulate Drought Stress in Bulgarian Wheat

Drought occupies a dominant share among the environmental factors that directly cause significant economic losses. Wheat is one of the most important crops for humankind, and although it tolerates drought to a certain extent, prolonged water deficit provokes a number of unfavourable alterations in plants, which lead to a significant decrease in productivity. Because of the broadening climate changes, the search for ecological biostimulants as an innovative approach to reduce the harmful effects of drought is gaining more popularity in modern agriculture. Melatonin is a natural product of plant metabolism with growth-regulating properties – it is non-toxic and is safe for the environment. We aimed to investigate the possibilities to modulate the negative effects of drought through application of melatonin using a comparative analysis of the physiological reactions of young wheat seedlings. We studied the effects of melatonin applied before drought on the physiological responses of two Bulgarian wheat cultivars grown as a soil culture. Different concentrations of melatonin ranging from 5 to 500 μM were tested and 75 μM was selected as a promising one. Additionally, we tested the method of application of melatonin – leaf spray or root supplement. Based on the content of selected stress markers we could make a conclusion that leaf spraying of plants before stress had some attenuating effect on the negative consequences of drought, but one dose of root application appeared to be more effective. Abbreviations: MDA – malondialdehyde, Mel – melatonin, ROS – reactive oxygen species

Oral health inequalities in immigrant populations worldwide: a scoping review of dental caries and periodontal disease prevalence

BackgroundInequalities in immigrants' oral health are often masked in population-level data. Therefore, this paper was planned to assess the prevalence data on oral health diseases, namely dental caries, and periodontitis, among immigrants worldwide.MethodsFollowing a systematic search in Scopus, Embase, and PubMed for studies published between 2011 and 2023, 1342 records were identified. Following title and abstract screening, 76 studies remained for full-text eligibility-screening based on predefined inclusion criteria. Thirty-two studies were included in the review.ResultsDental caries figures were higher in immigrant populations compared to the local population, regardless of host countries, age, gender, or nationality. In children, the overall mean and standard deviation (SD) for decayed, missing, and filled teeth in the primary dentition (d3mft) was 3.63(2.47), and for D3MFT (permanent dentition), it was 1.7(1.2).Upon comparing overall mean caries counts in children and adults with their control groups in the included studies, untreated dental caries (D3T and d3t) constituted the dominant share of caries experience (D3MFT and d3mft) in immigrant children. For the local population, the highest proportion of caries experience was attributed to filled teeth (FT and ft).Dentin caries prevalence among immigrants ranged from 22% to 88.7% in the primary dentition and 5.6% to 90.9% in the permanent dentition. Gingivitis ranged from 5.1% to 100%. Oral health varied greatly between studies. Regarding oral health accessibility, 52% to 88% of immigrant children had never been to a dentist, suggesting a very limited level of accessibility to dental health services.ConclusionIt is imperative to develop interventions and policies that have been customized to address the oral health disparities experienced by immigrant populations. Additionally, host countries should actively implement measures aimed at enhancing the accessibility of oral health care services for these individuals. The utilization of available data is crucial in establishing a hierarchy of objectives aimed at enhancing the oral health of immigrant populations.Trial registrationThe Scoping review protocol was registered at OSF Registries with registration number (https://doi.org/10.17605/OSF.IO/MYXS4).

Vitamin C: Overview of drugs and dietary supplements and analytical methods for determining its content

Vitamin C is one of the most well-known and most frequently used substances found in various pharmaceutical preparations. Patients consider it as a safe compound with multidirectional beneficial effects, while chemists have been presenting various possibilities for its determination for many years. The aim of this review is to present the current range of drugs and dietary supplements containing vitamin C available in Poland, divided into appropriate categories, taking into account doses, forms and other ingredients. The second goal is to summarize the main analytical methods for determining the content of ascorbic acid. A review of available preparations showed disproportions between a small group of drugs and a very large group of dietary supplements, which turned out to be significantly diversified in various aspects. In turn, the review of analytical methods clearly indicates the dominant share of spectroscopic ones and the fact that researchers focus primarily on improving basic, commonly known techniques.

Nutrient and organic substances emissions from diffuse sources to the rivers of Ukrainian Carpathians

Formulation of the problem. The transition from territorial-administrative to basin-based water resources management in Ukraine requires an assessment of the load of water bodies with pollutants from diffuse and point sources. Among the various components of the chemical composition of water entering water bodies, organic matter and nutrients are the most important. The Danube is the second largest river in Europe, with a basin covering the territories of 19 countries and is an important transportation waterway. Within Ukraine, the Danube is divided into the Lower Danube sub-catchment and the Tisza, Prut, and Siret River basins within the Carpathian region. The scientific results presented in this paper were obtained during research within the framework of state budgetary research works of the UHMI, the implementation of which will contribute to the further development of knowledge in the field of hydrometeorology. The results presented in the publication are important for supplementing information when writing the Danube River Basin Management Plan, which is being developed in accordance with Ukraine's obligations under the Association Agreement with the European Union. Aim of the study. To calculate the supply of nutrients and organic matter from diffuse sources to the rivers of the Danube basin within the Ukrainian Carpathians. Methods. Monitoring data of organic substances and nutrients provided by the Danube Hydrometeorological Observatory (the state surface water monitoring network of the State Emergency Service of Ukraine) for 2018 were used for calculations. To assess the load of water bodies by diffuse sources, a conceptual scheme was developed that allowed to take into account the main pathways of substances supply, i.e precipitation; water runoff from arable land, forests, meadows and pastures, built-up areas, rock outcrops, as well as from the population of rural regions without sewage systems. Scientific novelty. For the first time: the load of nutrients and organic matter in the Danube rivers within the Ukrainian Carpathians by the sources of their income was evaluated; it was found that agricultural land is the main source of emissions of inorganic nitrogen and phosphorus compounds. Practical value. The analysis of the diffuse load by nutrients and organic matter in the Danube rivers can be used as an important part of the River Basin Management Plan. The results of the calculations can also be used to develop measures to achieve certain environmental objectives. Results. The main source of organic matter in the water of rivers of the Carpathian region ere agricultural enterprises locating within rural settlements that are not equipped with sewage systems. Surface water of Prut and Tisza River basins is the most polluted by organic matter. By source, the nutrient emissions are distributed as follows. For the Tisza and Prut rivers, more than 50% of the total nitrogen compounds emissions come from agricultural land, while for the Siret River the source of nitrogen compounds are forests (46% of the total nitrogen emissions). Accordingly, the total phosphorus runoff for the Tisza and Prut rivers was distributed as follows: the dominant share (up to 45%) comes from agricultural land, the load caused by population not connected to the sewerage systems is 36%. For the Siret River, agricultural land and forested areas are of equal shares (33%) among the sources of phosphorus compounds.

Pseudoscalar Mesons and Emergent Mass

Despite its role in the continuing evolution of the Universe, only a small fraction of the mass of visible material can be attributed to the Higgs boson alone. The overwhelmingly dominant share may/should arise from the strong interactions that act in the heart of nuclear matter; namely, those described by quantum chromodynamics. This contribution describes how studying and explaining the attributes of pseudoscalar mesons can open an insightful window onto understanding the origin of mass in the Standard Model and how these insights inform our knowledge of hadron structure. The survey ranges over distribution amplitudes and functions, electromagnetic and gravitational form factors, light-front wave functions, and generalized parton distributions. Advances made using continuum Schwinger function methods and their relevance for experimental efforts are highlighted.

Small business development in stabilizing Alberta’s economy (Canada)

This paper considers small businesses as an effective sector that solves current problems in the structure of the economy. The study aims to develop a set of measures (tools) for involving small businesses in stabilizing Alberta’s economy. The methodology includes the monitoring of the economy within Alberta’s regional borders over time; statistical analysis of the small business sector before and during the pandemic in the structure of the economy; as well as grouping and converting quantitative measurements into a qualitative summary of the main economic principles. These steps are aimed at developing a set of measures (tools) for involving small businesses in the economy of the province and the country as a whole. The growth of small enterprises ensures a practice focused on productivity, innovation, and society, which is confirmed by the dominant share of small businesses in the gross domestic product created by the dominant share of small businesses in the gross domestic product created by the private sector of the province. Thus, focusing on the economic principles of small businesses, a complex of measures is proposed for mobilization to maximize the economic result at the provincial level in the context of strengthening the national economy. In practice, the findings will help the local government to determine a set of beneficial policies, contributing to the utilization of the advantages of the local economy in the sphere of business production. Entrepreneurs are provided with an opportunity to qualitatively utilize economic opportunities, recognizing the risks of the external environment.

Numerical analysis of transport phenomena in a steam reforming reactor with optimal multi-segments catalyst distribution

The contemporary industrial trends pursue alternative energy sources, to substitute fossil fuels. The current direction is induced by concerns regarding exhausting natural resources and the environmental impact of the technologies rising globally. Conventional technologies have a dominant share of the current energy market. The most crucial issue with current technology is the emission of greenhouse gases and their negative impact on climate. One of the possible approaches to limit the issue of emissions is the steam reforming of natural gas, leading to the production of hydrogen. Fuel cells are a robust technology, able to conduct a catalytic conversion of hydrogen and oxygen, for the direct production of electrical energy. Fuel cells are one of the most environment-friendly technologies to this day, as their exhaust gases mostly consist of steam. Currently, almost 50% of the hydrogen produced is acquired via hydrocarbons reforming. The process described in the presented analysis occurs between methane and steam. The presented numerical analysis regards small-scale reactors, which are more suitable when it comes to the processing of distributed or stranded resources for hydrogen production To optimize the small-scale unit’s performance, the macro-patterning strategy is introduced. Steam reforming has a strong endothermic character and tends to produce unfavorable thermal conditions. The process enhancement is acquired by introducing non-catalytic regions to the catalytic insert geometry. The non-catalytic segments are introduced to suppress the reaction locally, decreasing the magnitude of temperature gradients. Unification of the temperature distribution is proven to increase the reforming’s effectiveness. The presented analysis introduces a new approach to the catalytic insert division, to investigate if a complete temperature field unification is possible. The catalytic insert is simultaneously divided along the reactor’s radius and length, resulting in a set of concentric rings, placed along the reactor’s axis. The calculations are conducted using in-house numerical procedure, coupled with a genetic algorithm. The algorithm optimizes the process effectiveness by modification of the segment’s alignment and porosity.

Multifunctional coatings for solar module glass

AbstractCurrently, single‐layer antireflection coated (SLARC) solar glass has a dominant market share of 95% compared to glass with other coatings or no coating, for Si PV modules. This antireflection coating (ARC) results in an efficiency gain of 2–3%. However, there are issues with these SLARCs: (1) solar cell warming due to increased sub‐bandgap light absorption (by +0.4 ~ 1.2 K), counteracting the cell current gain and accelerating the aging of the solar panels, and (2) poor durability due to the coating's porous structure (typically lasting ≤5 years). This paper aims to develop a non‐porous multilayer coating (MLC) that is more durable and will act as a spectrally selective filter for solar modules. Studies have been conducted on MLCs in terms of optical, microstructure, mechanical, and durability properties compared with commercial single‐layer AR coatings. The MLCs showed superior performance in durability and benefit in reducing parasitic heat absorption in the non‐usable wavelength range. Also, a techno‐economic analysis model based on the multifunctional coating specifically to evaluate economic benefits has been developed.

Nintendo’s new normal?

Research methodology This case was written with publicly available information about Nintendo. Case overview/synopsis In the 1980s and 1990s, Nintendo dominated the video game industry with a market share of 90%. In 2020, Nintendo’s market share dropped to nearly 31%. This case examines a 40-year history of Nintendo, including its core strategy of video game and video game console development and its growth strategy using its intellectual property. Throughout its history, Nintendo has faced and continues to face stiff competition from Sony, Microsoft and new emerging technologies like virtual reality video games. Nintendo has the challenge of competing in a rapidly changing industry with changing customer preferences where it once had a dominant market share. Can Nintendo continue competing, relying on its core competency of developing new video games and consoles? Or moving forward, should it further define itself more broadly by continuing to leverage its intellectual property in the entertainment industry? Complexity academic level This case is suitable for undergraduate courses in marketing, marketing management and business strategy, or where an instructor focuses on strategic decision-making. This case will provide valuable in-class discussions on the importance of defining what a business should do and how it should grow. Additionally, this case will be useful for courses that include advanced discussions on tradeoffs between focusing on core competencies and growth by expanding into other opportunities that are not necessarily part of a business’s core strategy. A portion of this case was tested in an undergraduate marketing strategy and marketing principles course. The case created an excellent environment for critical thinking and analysis.

The Use of Thermoporometry in the Study of Frost Resistance of Rocks.

From an engineering point of view, it is important to know the factors influencing the frost resistance of rocks with porosity above 2% due to their different frost resistance. The article focused on frost durability research using the thermoporometry method (TMP) and the assessment of water phase transition in the pore spaces of selected rocks. For this purpose, the differential scanning calorimetry method (DSC) was used with the adoption of an original algorithm for eliminating the thermal inertia of the measurement system. The results of the DSC method were supplemented with the results of pore size distribution using the mercury intrusion porosimetry method (MIP) and standard rock frost resistance tests. Based on the research carried out using the thermoporometry method, it was confirmed that the ability of water to freeze in the temperature range from -5 °C to -20 °C was important, as well as the ability of rocks to increase the degree of water saturation during freeze-thaw cycles. Based on calorimetric tests combined with thermoporometry, in the case of non-frost-resistant rocks, a significant (dominant) share of pores with a radius of under 10 nm (amounting to over 0.008 cm3/cm3) was found. Pore connections in the water freezing process do not influence the investigated rocks' frost resistance.

A Regression Model of Dry Bulk Carriers’ Loading Time

Abstract Although optimization of Vessel Turnaround Time (VTT) is a well-known research problem and its importance has long been understood, research on dry bulk carriers VTT has no priority in the available literature. It is one of the initial motives of the author to write this paper. After a general theoretical introduction, this paper presents research on dry bulk carriers’ loading time, as a component with the dominant share in the total VTT. Through the research, a mathematical model of interdependencies between dry bulk carrier‘s loading time and selected independent variables is defined using a multiple linear regression model. Results of statistical significance tests confirmed that the best-fit regression model is the one which adequately describes the correlation between the dry bulk carrier‘s loading time and the following independent variables: cargo quantity (loaded), number of used cranes per vessel and loading process interruptions. The presented results establish important bases for the author’s further research in this field as well as reliable planning bases for cargo handling management processes at dry bulk cargo terminals where cargo loading/unloading to/from vessels is realized by gantry cranes and/or mobile harbour cranes.

Urban form and daily mobility on the outskirts of Constantine (Algeria): Case of the new town of Ali Mendjeli

This article presents the results of research into the impact of urban form on mobility practices in the outskirts of Constantine, which has experienced spectacular urban growth in recent years. Like other Algerian cities, Ali Mendjeli is one of the most unusual urban forms to have arisen from the saturation of the mother city, and has undergone rapid urban expansion, marked by the concentration of major facilities and services. This has led to several urban dysfunctions, reflected in longer distances travelled, strong growth in the number of journeys and increased use of the car, resulting in saturation of the road network and the inefficiency of public transport, which can no longer cope with high demand, and the emergence of informal transport. In fact, the household travel survey carried out in 2020/2021 revealed that the distance between home and work increases with distance from the town center, with a correlation coefficient of R? = 0.78. In addition, the urban layout of Ali Mendjeli is difficult to navigate on foot, with the private car the most dominant modal share, and public transport is still in deficit due to the poor quality of its offer.

A Statistical Survey on the Socioeconomic and Demographic Livelihood of Brick Kiln Workers: A Case Study of Bahawalpur District, Punjab, Pakistan

The working population at the brick kilns is considered as the people living under poverty line. This study aims to investigate the socioeconomic and demographic characteristics and housing and living conditions of the brick kiln workers in Bahawalpur district. Total 20 kilns were visited in 5 tehsils of the district as sample sites. A questionnaire was designed and a field survey was conducted by using simple random sampling techniques to collect the data of 400 workers from 20 brick kilns. The quantitative analysis was performed in Statistical Package for Social Sciences (SPSS) v. 21 by applying descriptive and inferential statistics. Findings showed that majority of the workers and heads of working households were male (85.75% and 97.5% in rural and urban kilns respectively) and Saraiki speaking (70%) belonged to Muhajir, Ranagr and Khokhar castes. The early age (14-18 years) marriages were common among the workers especially among the females. Dependency ratio of the kiln workers was 37.6% including mostly the children and aged. Dominant share of the kiln workers (70-80%) were illiterate and very few were literate from primary to intermediate level. The workers’ income varied between PKR 11,000 to 15,000 which was lower than the average wage (PKR 25,000) as per the government rules. Brick moulders and soil suppliers were the main occupants at kilns. Most of the workers were resided in their own houses (1 or 2 rooms) made with kacha (mud made) material. Although various facilities were available to the workers at brick kilns but they have no proper access to safe drinking water (80%), accident risk facility (0%) and first aid (0%) crucial for their health. The chi-square results also verify the miserable social and economic life of the kiln workers. Thus, these facts demonstrated that kiln workers led a meagre life style. This work will serve as a reminder to authorities, planners and Non-Governmental Organizations (NGOs) to take action to improve the living conditions of kiln workers. Lastly, few suggestions were proposed to uplift the lives of the kiln workers.

Conventional Fossil Fuel Extraction, Associated Biogeochemical Processes, and Topography Influence Methane Groundwater Concentrations in Appalachia.

The production of fossil fuels, including oil, gas, and coal, retains a dominant share in US energy production and serves as a major anthropogenic source of methane, a greenhouse gas with a high warming potential. In addition to directly emitting methane into the air, fossil fuel production can release methane into groundwater, and that methane may eventually reach the atmosphere. In this study, we collected 311 water samples from an unconventional oil and gas (UOG) production region in Pennsylvania and an oil and gas (O&G) and coal production region across Ohio and West Virginia. Methane concentration was negatively correlated to distance to the nearest O&G well in the second region, but such a correlation was shown to be driven by topography as a confounding variable. Furthermore, sulfate concentration was negatively correlated with methane concentration and with distance to coal mining in the second region, and these correlations were robust even when considering topography. We hypothesized that coal mining enriched sulfate in groundwater, which in turn inhibited methanogenesis and enhanced microbial methane oxidation. Thus, this study highlights the complex interplay of multiple factors in shaping groundwater methane concentrations, including biogeochemical conversion, topography, and conventional fossil extraction.

Change Management in a South African Municipality: Can it Work?

The business environment is ever-changing, and even companies with dominant market share needs to keep up with these changes. Not all change initiatives prove to be successful. Numerous obstacles have been highlighted in literature such as a lack of communication and poor support from management. This study, therefore, set out to identify the different factors that affect the successful implementation of change management initiatives in the City of Tshwane Metropolitan Municipality. The study followed a quantitative method, and the primary data was collected by means of an online questionnaire through SurveyMonkey. The data was analysed via SPSS software and presented in graphs and tables for easy interpretation. The results and knowledge gained from this study will add to the existing body of knowledge in the discipline. It might also assist municipalities to effectively identify and quantify factors that affect their ability to manage constructive change at the workplace. All ethical requirements were considered during the study. The outcome of the study indicated that managers seem to be unaware of the benefits and principles of change management. Organisational structures and processes were found to be key contributors to the employees’ resistance to change. The participants also displayed uncertainty whether communication, employee readiness for change initiative, leadership, and resources were fully addressed in the implementation of change management. The study therefore recommended that the city presents awareness sessions to all city employees including managers on the change management models, the principles of change management as well as the benefits of implementing such models and principles in the operations of the City of Tshwane. The study further recommended that the city provides the required resources for the implementation of change initiatives, and fully address the requirements for communication and employee readiness for change initiatives.

Market Mechanism Design of Inertia and Primary Frequency Response With Consideration of Energy Market

The shortage of inertia and primary frequency response (IPFR) will be more severe in future power systems since conventional fossil-based synchronous generators are gradually being replaced by variable renewable energy (VRE) generators. To relieve the shortage of IPFR, corresponding market mechanisms should be designed and incorporated to motivate appropriate provision from various sources. The mechanism of IPFR provision from different types of generators and its tight relation with energy production should receive particular attention. This paper proposes a novel IPFR market mechanism in which the energy market is taken into joint consideration. The virtual inertia and droop factor provided by VRE generators are defined and introduced, considering its dominant share in future power systems. A differentiated pricing scheme is designed towards incentive compatibility, considering provision from different types of generators with different quality levels and opportunity costs. Then, the proposed IPFR market mechanism is formulated, and a modified piecewise linearization method is utilized to simplify the non-linear nadir constraints. Finally, the model is tested on a modified IEEE 30-bus system according to historical data in CAISO. The results indicate the proposed mechanism could increase the utilization of VREs, decrease system operation costs, and guarantee reasonable payback for various types of generators.