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The urgent need to combat climate change has driven the search for sustainable transportation solutions. Electric vehicles (EVs) and hydrogen fuel cell vehicles (FCVs) have emerged as promising alternatives to traditional fossil fuel-powered cars, offering the potential to significantly reduce carbon emissions. This article provides a detailed analysis and comparison of these two technologies, focusing on their technical, economic, and environmental aspects. EVs rely on batteries to store electrical energy, which ...

This paper focuses on analyzing the behavior of a photovoltaic system installed on a selected building, using the PVcase software to evaluate the influence of temperature on energy performance. The study simulates a typical summer day, comparing the operation of photovoltaic panels during two distinct periods: in the morning, when the ambient temperature is lower, and at midday, when the temperature reaches its peak. Through these simulations, variations in voltage, current, and generated power are determined, as ...

Hydrogen is considered the energy source which can ensure the global transition to sustainable low-carbon energy systems. Municipalities can become more eco-friendly by adopting and implementing hydrogen-based energy systems. At the beginning of the transition toward carbon neutrality, the municipalities can use the hydrogen mixed with natural gas in the existing natural gas network for food and domestic hot water preparation, and heating and electricity generation, and the hydrogen stored as compressed gas, cryo-...

This paper presents the modeling and simulation of an electrical energy management system that integrates a 300 V, 8 Ah lithium-ion battery, a DC shunt machine, and a variable DC load using NEPLAN simulation software. The main purpose of this work is to investigate the performance and control behavior of a hybrid electrical system where the power flow is automatically regulated according to the State of Charge (SOC) of the battery. The DC machine alternates between motor and generator modes depending on the SOC le...

Complex energy systems, in the current period of transition to a climate-neutral society, comprise two fully functional subsystems, that of fossil fuel-based production and that of production from renewable energy sources. The functional coexistence of these subsystems is achieved due to the capture of the CO2 component from flue gases through the energy vector represented by green H2. This takes on both the role of energy accumulation and the role of transforming the CO2 component, captured during the combustion ...

The transition to renewable energy sources is a key strategy for reducing carbon emissions and ensuring energy sustainability. This study explores the integration of photovoltaic (PV) systems for hydrogen production and storage in Constan?a County, Romania. The region benefits from high solar potential, making it an optimal location for implementing solar energy solutions. The proposed system converts solar energy into electricity through photovoltaic panels, which is then used to power an electrolyzer for hydroge...

This paper explores the operational characteristics of a DC islanded microgrid engineered to produce green hydrogen, utilizing power sourced from a solar array complemented by an energy storage system. The model simulates a one-week evaluation period, incorporating comprehensive analyses of electrical, thermal liquid, and thermal gas domains. By examining the interactions between the solar array, energy storage, and electrolyzer, the study provides a detailed assessment of system performance under varying conditio...

This paper presents an in-depth analysis of a residential solar thermal system designed for domestic hot water (DHW) production in a single-family dwelling located in Mangalia, Romania. Positioned at a latitude of 43.894- and a longitude of 28.422-, Mangalia benefits from an annual global irradiation of 1403 kWh/m?, providing favorable conditions for solar energy utilization. The study evaluates the system's performance over the course of a year, focusing on energy consumption, solar fraction, and environmental be...

The use of hydrogen as a fuel requires as much research as possible on the construction and functional parameters for the development of appropriate burners. The researches undertaken are addressed to diffuse flame burners with concentric jets of fuel and air. These burners cannot lead to flame return, the combustion being much safer, than for the case of burners with fuel-air mixture. The researches were carried out by numerical modeling through the ANSYS-FLUENT V.14.0 software. An important stage of the research...

In the energy field hydrogen will be more obvious to use by certain technologies than by direct combustion. The paper presents a conceptual analysis on the use of hydrogen by hydrogen by hydrogenation of carbon dioxide with final product methane, by hydrogenation of carbon dioxide, with the final product of methanol and by injection in certain proportions into the natural gas network. A new application of carbon dioxide hydrogenation is the decarbonisation of flue gases. To this end, conceptual analyses have been ...

This paper presents a model for super-rapid charging stations powered by renewable energy sources and conducts an analysis of land suitability based on climatic parameters. Initially, data on temperature, solar radiation, and specific humidity were collected for three designated areas, followed by an examination of the variations in these values. Among the three cities, Cernavoda, Medgidia, and Ovidiu, two equal segments of approximately 30 kilometers each were established for the installation of photovoltaic pane...

Challenges related to the management of current world energy resources strongly emphasize the necessity to progressively increase renewable energy sources (RES) share in meeting electricity demand. To design efficient and sustainable energy systems, it is mandatory to consider both electrical energy generation characteristics and environment preservation targets. The main objective of intensifying RES deployment nowadays is to concurrently mitigate fossil fuels depletion and environment degradation. However, to ac...

Renewable resources? share in meeting the power balance in Romania grew constantly during the past decade. Therefore, the contribution of polluting energy sources (such as coal or oil) has progressively reduced. Moreover, to enable environmental impact mitigation for the still operating classical plants, proper desulphurization equipment were installed. It is remarked that the shares corresponding to hydro-energy and nuclear energy show an almost constant trend. Sensible investments were made in the energy sector,...

Environmental restrictions get every day more demanding; therefore, energy policies focus on reducing greenhouse gas emissions, setting clear targets relative to the renewable energy contribution in meeting electricity demand. Thus, the global tendency towards fossil fuel replacement by renewable energy sources (RES) is progressively sharpening. Sustainability of power systems with high renewable energy penetration rates is a topic of major interest, especially considering the intermittency of RES production and t...

The first part of the paper analyses the role of renewable resources in the production of electric and thermal energy in Romania. It was taken in consideration also the wood mass destined to heating the population, as a large number of households still use this fuel exclusively. Starting from the plough land and its associated production, there is the availability of agricultural biomass possible to use for energy production. The paper is concluded with the final considerations on the benefits of using biomass for...

One of the main environmental issues of society today is the continuous increase in the amount of organic waste. Sustainable organic waste management no longer supports old practices that involved uncontrolled releases, landfill storage or incineration. A potential solution is converting organic matter into energy. Previous papers dealt with energy recovery of animal proteins and fats from tanneries into biogas and biodiesel after separation of the two components by pressing-centrifugation at temperatures of 60-80...

Different operations, such as fleshing, trimmings, cuttings and chips from hides, causes leather industry in being one of the most environmental пїЅunfriendlyпїЅ sectors. Moreover, the treatment of sewage waters brings up also the problem of mud which is related with the appearance of biodegradation process of organic waste, followed by the emission of greenhouse gases, especially methane and nitrous oxide. All these wastes also imply a terrible smell and a strong land contamination. The large quantity of wastes, ...

Due to high quantities of animal fat resulted from leather industry, the necessity of a solution in order to neutralize the negative effects that appear by their discharge into the nature has led to continuous research in order to obtain the most suitable one for solving the environmental issue with energy recovery. Between combustion and chemical treatment, the combustion has been chosen in this study as being the most effective one, by technical and economical criteria. Before this combustion, there were perform...

The leather sector is an important source of materials for various industries and fields.This industry generates a big quantity of solid and liquid waste.The whole process that the skin is subjected to contains a series of operations and chemical reactions.Waste from the leather industry can be obtained by using multiple processing methods in different areas. Recovery of waste from the leather industry is an important factor for environmental protection. Nowadays, the elaboration of leather processing methods that...