Energy, Mechanical Engineering, Energy Engineering and Power Technology
23
Scopus Publications
Scopus Publications
Real-Time Energy System Optimization and Resilience Analysis in Low-Voltage Networks Using Intelligent Edge Computing Dan Cristian Lazar, Dan Codrut Petrilean, Teodora Lazar, Florin Gabriel Popescu, Daria Ionescu, Adina Milena Tatar, Georgeta Buica, Dragos Pasculescu Processes, 2026 The transition toward active distribution networks requires advanced control solutions capable of handling the rapid dynamics of distributed energy resources. This paper proposes a low-cost, intelligent IoT architecture designed for the real-time optimization and analysis of energy systems within low-voltage networks. Unlike centralized monitoring approaches constrained by communication latency, the proposed solution leverages Intelligent Edge Processing (IEP) implemented on ESP32 embedded nodes to optimize data flow and decision-making. This architecture executes stability assessments directly at the network edge, calculating critical analysis indicators such as the Voltage Deviation Index (VDI) and Rate of Change of Frequency (RoCoF). The system was validated on the CIGRE European LV benchmark under severe stress scenarios, including rapid solar transients and voltage sags. The results demonstrate that the proposed architecture effectively coordinates storage interventions, ensuring voltage recovery within 300 ms and maintaining power quality within EN 50160 limits even during severe voltage sags. The study validates the feasibility of using industrial IoT edge computing as a resilient, non-wire alternative for modernizing complex energy systems.
Research on the Valorization of Calcium Chloride from Green Sludge Resulting from the Manufacture of Sodium Dichromate in Romania Camelia Traistă, Eugen Traistă, Maria Lazăr, Alexandru Mihai, Dan C. Petrilean Circular Economy and Sustainability, 2025 The Târnăveni Chemical Plant was a inorganic chemical plant in Romania. In the good old days, even 6,500 employees worked here. When it was productive, the Chemical Plant produced a lot of inorganic products such as: sodium bichromate, potassium bichromate, barium salts, chromium salts, or zinc oxide. In 2002, the plant was closed and taken over by AVAS. The sodium (potassium) dichromate manufacturing process results in a tailings called green slime. The tailings deposited in the landfill are strongly contaminated with dichromate ion, as a result of the process of manufacturing chromium salts. In a first stage, the recovery of the chromate and magnesium ions from this sludge were investigated. In the continuation of the valorization process of these slurries, the recovery of calcium is pushed. Calcium recovery is achieved by leaching with ammonium chloride.
Assessment of steam turbine performance degradation in long-term operation Ion Dosa, Dan Codrut Petrilean, Andreea Cristina Tataru, Gabriel Dragos Vasilescu, Nelu Mija, Alin Marian Cazac, Oana Rusu, Anca-Cristina Tatarcan, Costica Bejinariu Energy, 2025 Sustainable Development Goal 7 is about affordable and clean energy for all. The push for decarbonization, with most countries aiming to reach net zero by 2050, will lead to the decommission-ing of many fossil fuel power plants. These plants are complex and costly to build, making repurposing a viable alternative. As a result, studies are exploring ways to convert them to operate on alternative fuels. The steam turbine is one of the most expensive components in a power plant. Over time, prolonged operation can lead to a decline in its efficiency. In order to be used further, the extent of efficiency loss must be assessed, which represents the purpose of the study. The results indicate that power loss ranges from 2.03 % for the 210 MW turbine to 7.51 % for the 150 MW turbine. The analysis of isentropic efficiency of the high pressure, reheat and low-pressure turbine revealed that actual working conditions have an important impact on overall efficiency and pow-er output of the turbine, maybe even more than long-term operation. The power loss can be considered moderate, and anytime it is technically possible, repurposing the steam turbine should be taken into account.
Sustainability Management Through the Assessment of Instability and Insecurity Risk Scenarios in Romania’s Energy Critical Infrastructures Dan Codruț Petrilean, Nicolae Daniel Fîță, Gabriel Dragoș Vasilescu, Mila Ilieva-Obretenova, Dorin Tataru, Emanuel Alin Cruceru, Ciprian Ionuț Mateiu, Aurelian Nicola, Doru-Costin Darabont, Alin-Marian Cazac, Costica Bejinariu Sustainability Switzerland, 2025 In the current context of sustainability management and energy insecurity, amplified by the military instability determined by the war between Russia and Ukraine, and the increasingly frequent occurrence of a series of plausible scenarios for disasters or energy blackouts worldwide, this work is a real and applicable model for regional states that would like to critically analyze the situation of their energy security through identifying all the plausible risk scenarios targeting the energy critical infrastructures. The study has identified and assessed two of the most plausible risk scenarios (a natural disaster and a terrorist attack) in the case of a strategic power substation of 220 kV, 400 kV, or 750 kV undergoing a blackout effect. After having assessed the risks, the safety strategy for Romania’s national power system has been elaborated together with the safety strategy for the European Power system-ENTSO-E (European Network of Transmission System Operators for Electricity). The results of the study match other specialized works from different European countries and might represent a model for other types of energy safety risk assessments and for other types of critical infrastructures that are vital for the modern European society and for sustainability management.
Analysis of the causes of power crises and their impacts on energy security Nicolae Daniel Fîţă, Dan Codrut Petrilean, Ioan Lucian Diodiu, Andrei Cristian Rada, Adrian Mihai Schiopu, Florin Muresan-Grecu International Conference on Electrical Computer and Energy Technologies Icecet 2024, 2024 Without a safety and secure Power System, a state cannot function by the fact that all public systems are interdependent and dependent of electricity. This Power System is composed of several critical power infrastructures of major importance without which the economy and industry of any state in the world could not function. The access to electricity that is created by these critical infrastructures is a common right of every citizen (according with The United Nation 21 Agenda 1992 stated that “energy is essential for economical and social development and the improvement of quality of life”) and it empowers all citizens of a state to find technical and social solutions in times of peace, but also in times of crisis or war, to prevent, correct or managing a blackout. In every state around the world, the Power System is the most important and complex system in that it provides and facilitates critical, domestic and industrial consumers the electricity needed to have a normal life in safety and security. Every Power System is in total interdependence with other systems: food system, water supply system, transport system, health system, financial system, commercial system, administrative system, communication system-information, etc. Through this paper, the authors aimed to take a look at the history, causes and effects of some of the most devastating blackouts that occurred nationally and worldwide between 1977–2018.
The influence of humidity on air temperature in underground mines as a factor of air quality assessment Quality Access to Success, 2019
Energetic and environmental efficiency of cogeneration of a baking plant Journal of Environmental Protection and Ecology, 2019
Comparative energetic sustainability indicators for paroseni central heating power plant considering its cogeneration and condensing operation Journal of Environmental Protection and Ecology, 2018
Solutions for the capitalisation of the energetic potential of sludge collected in Danutoni wastewater treatment plant Journal of Environmental Protection and Ecology, 2015
Real exergetic balance sheet of rooftop Trane 60 kW International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2015
Real and optimum exergetic balance sheet of Helical screw compressor atlas COPCO GA 30 CF to reduce energy consumption International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2015
The energetic quantification of thermodynamic inefficiencies of hot water distribution networks International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2014
Efficiency of production and delivery of hot water obtained from waste heat International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2014
The assessment of the energetic performances of a district heating system International Multidisciplinary Scientific Geoconference Surveying Geology and Mining Ecology Management Sgem, 2014
Aspects of consumers' rights protection for the centralised Urban heating services Vision 2020 Innovation Development Sustainability and Economic Growth Proceedings of the 21st International Business Information Management Association Conference Ibima 2013, 2013
Research regarding the variation of the cost of fluido-dynamic lost energy on a pneumatic network of compressed air Wseas Transactions on Heat and Mass Transfer, 2010
Method of calculus for the power input of the helical screw compressor UPB Scientific Bulletin Series D Mechanical Engineering, 2009
