Article
Chemistry, Physical
Ayhan Atiz, Hatice Karakilcik, Mustafa Erden, Mehmet Karakilcik
Summary: The study investigates an integrated system for electricity and hydrogen production, with energy and exergy analyses. The system includes various solar collectors, flash turbine, organic Rankine cycles, reverse osmosis unit, water electrolysis unit, greenhouse, and medium temperature geothermal resource. By upgrading the fluid temperature from geothermal resources, clean water, hydrogen, and electrical energy are generated. The overall energy and exergy efficiencies of the system are found to be 10.43% and 9.35% respectively.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Green & Sustainable Science & Technology
Alireza Rafiei, Reyhaneh Loni, Shuhaimi B. Mahadzir, Gholamhassan Najafi, Milad Sadeghzadeh, Mohamed Mazlan, Mohammad Hossein Ahmadi
Summary: A hybrid energy conversion system was proposed and evaluated for power generation and freshwater production, with a focus on the influence of different nanofluids on system performance. Results showed improved thermal efficiency, freshwater production, and exergy efficiency with the application of specific nanofluids, while reducing CO2 emissions in the environment.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Green & Sustainable Science & Technology
Diogo do Carmo Zidan, Cristiana Brasil Maia, Mohammad Reza Safaei
Summary: Numerical simulations were conducted to predict the performance of PTC systems operating with eight different nanofluid compositions. The model also estimated daily incident solar radiation, beneficial energy gain, overall efficiency, thermal losses, and system pressure drop.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Energy & Fuels
Farhat Mahmood, Yusuf Bicer, Tareq Al-Ansari
Summary: Decentralized food production using a solar-powered multigeneration system can enhance resource utilization efficiency and produce electricity, freshwater, oxygen, hydrogen, and space cooling. The system consists of various components like collectors, cycles, desalination units, electrolyzers, combustors, storage, cooling systems, and structures, achieving high energy and exergy efficiencies through thermodynamic analysis and parametric studies for different outputs.
Article
Thermodynamics
Evangelos Bellos, Christos Tzivanidis, Zafar Said
Summary: This work investigates a solar-assisted pumped thermal energy storage system which utilizes solar collectors, a heat pump, a storage system, and an organic Rankine cycle. By analyzing with a mathematical program, it was found that the optimum storage temperature is 150℃ and the optimum temperature in the evaporator of the heat pump is 75℃, resulting in a power recovery ratio of 68.48%, an organic Rankine cycle efficiency of 18.45%, and a heat pump coefficient of performance of 3.704.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Thermodynamics
Alireza Rafiei, Reyhaneh Loni, Gholamhassan Najafi, Shuhaimi B. Mahadzir, Evangelos Bellos, Mohsen Sharifpur, Mohamed Mazlan
Summary: The study focuses on a solar desalination system incorporating an organic Rankine cycle for power and freshwater production, highlighting the efficiency and environmental benefits of the system. Through experimental and numerical analysis, it was found that the corrugated tube design outperformed the smooth tube in terms of freshwater production and CO2 emission reduction.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Environmental Studies
Mahdi Movasaghi Gilani, Masoud Torabi Azad, Mohammad Hassan Khoshgoftar Manesh, Kamran Lary, Gholamreza Salehi
Summary: This study proposes a novel power and potable aqua creation system that combines gas cycle, steam cycle, multieffect desalination, reverse osmosis desalination units, organic Rankine cycle, and solar thermal collector. The system is evaluated using 6E assessments and dynamic analysis, showing its feasibility and performance advantages.
ENERGY & ENVIRONMENT
(2023)
Review
Green & Sustainable Science & Technology
Alibakhsh Kasaeian, Koosha Mirjavadi, Peyman Pourmoghadam, Faezeh Asgari Sima, Yasaman Amirhaeri, Sara Borhani, Leila Fereidooni
Summary: This paper provides a detailed review of the literature on parabolic trough collectors (PTC) combined with organic Rankine cycles (ORC). It examines various aspects such as modeling and simulation, optimization, exergy, economics, and experimental studies. The review also highlights the impact of different parameters on the performance of the proposed systems.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Thermodynamics
Mohamed Abdelgaied, A. E. Kabeel, A. W. Kandeal, H. F. Abosheiasha, S. M. Shalaby, Mofreh H. Hamed, Nu Yang, Swellam W. Sharshir
Summary: This study successfully simulated a new hybrid desalination unit merging humidification-dehumidification and reverse osmosis techniques, utilizing photovoltaic systems for power and thermal energy recovery units to enhance freshwater production and energy efficiency.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Energy & Fuels
Tianbiao He, Jibao Zhang, Ning Mao, Praveen Linga
Summary: Clathrate hydrate-based desalination is a promising but energy-intensive technology. By utilizing LNG cold exergy, a sustainable process integrated with an organic Rankine cycle was proposed to simultaneously generate fresh water and electricity. Economic analysis showed that this proposed process could achieve zero specific energy consumption for desalination and generate extra power.
Article
Green & Sustainable Science & Technology
Alireza Naminezhad, Mahmood Mehregan
Summary: This study analyzes the energy and exergy of a solar-driven organic Rankine cycle (ORC) system and its integration with reverse osmosis (RO) desalination systems and a multi-effect distillation (MED) desalination unit. The results show that increasing solar radiation intensity and collector module length leads to higher ORC power output and produced freshwater. The volumetric flow rate of the collector affects the temperature and mass flow rate of the output fluid, with the highest net power output achieved at a volume flow rate of 11000 lit/min. The study also highlights the significance of the solar collector as the system's heat source.
Review
Thermodynamics
Arvind Kumar, Zafar Said, Evangelos Bellos
Summary: The evacuated tube solar collector is a suitable solar technology for producing useful heat in various climate conditions. Design parameters such as tracking system, collector design, mass flow rate, optical design, and working fluid play crucial roles in influencing the performance of the collector.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Review
Green & Sustainable Science & Technology
Ashok Kumar Singh, Samsher
Summary: This paper reviews the performance of ETC assisted solar desalting units, especially emphasizing the advantages of thermosiphon ETC solar desalting units in addressing freshwater scarcity, and highlights their self-sustainability in remote areas.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Energy & Fuels
Deepak Tiwari, Deepali Atheaya, Anil Kumar, Nishant Kumar
Summary: In this study, a thermodynamic model of the solar power organic Rankine cycle (ORC) was proposed. The model was developed in MATLAB 2018a for a Cyclohexane/R123 mixture-based ORC system driven by a series of N-collectors. Four different collector models were integrated with the ORC system and evaluated for their thermal performance. The results showed that the N-series connection of conventional compound parabolic collector (NCCPC) system performed the best, with the highest collector exit temperature, heat gain, thermal efficiency, and exergetic efficiency.
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
(2022)
Article
Energy & Fuels
Eydhah Almatrafi, Francesca Moloney, D. Y. Goswami
Summary: This paper analyzes an innovative design of low-temperature multi-effect desalination system powered by a supercritical organic Rankine cycle (SORC) utilizing a low-grade solar heat source. The system has the potential to efficiently desalinate high salinity water or effluent streams from power plants, with lower energy consumption and higher efficiency compared to other systems.
JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME
(2022)
Article
Thermodynamics
George Kosmadakis, Panagiotis Neofytou
Article
Thermodynamics
Dimitrios C. Rakopoulos, Constantine D. Rakopoulos, George M. Kosmadakis, Evangelos G. Giakoumis
Article
Chemistry, Physical
G. M. Kosmadakis, D. C. Rakopoulos, C. D. Rakopoulos
Summary: The study investigates the cyclic variability in a spark-ignition engine fueled with methane/hydrogen blends using an in-house CFD code. It follows a recent methodology to accurately predict the COV of IMEP in a fraction of time. Results show that the methodology provides reliable predictions for a range of operating conditions, with a focus on engine cycle variations and NO emissions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Green & Sustainable Science & Technology
Fatima Baptista, Patricia Lourenco, Vasco Fitas da Cruz, Luis Leopoldo Silva, Jose Rafael Silva, Manuela Correia, Pietro Picuno, Evangelos Dimitriou, Georgios Papadakis
Summary: Higher education institutes are crucial for integrating sustainable development into the educational system, MSc programmes should include interdisciplinary courses related to sustainability, traditional face-to-face training methods are still considered important, while online learning has become more significant due to the pandemic.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Green & Sustainable Science & Technology
Bas Paris, George Papadakis, Rainer Janssen, Dominik Rutz
Summary: Currently, advanced biofuels, renewable gases, and electrofuels are not cost competitive with fossil fuel equivalents in Greece. However, with certain policy interventions, some of these fuels could become competitive with fossil fuels in the future.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Chemistry, Multidisciplinary
George Kyriakarakos, George Papadakis
Summary: Water and energy are vital inputs for community development. With limited freshwater resources, desalination has emerged as a solution, especially when powered by renewable energy sources. This approach effectively addresses water scarcity issues while reducing environmental impact.
APPLIED SCIENCES-BASEL
(2021)
Article
Energy & Fuels
Dimitrios C. Rakopoulos, Constantine D. Rakopoulos, Evangelos G. Giakoumis, George M. Kosmadakis
Summary: This study developed a comprehensive, quasi-dimensional, two-zone combustion model to predict the combustion characteristics, performance, and emissions of high-speed spark-ignition engines. The validated model showed good agreement with experimental data, providing insights into engine performance and emission attributes. The results shed light on the underlying physical and chemical mechanisms influencing SI engine performance and emissions.
JOURNAL OF ENERGY ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Bas Paris, Foteini Vandorou, Dimitrios Tyris, Athanasios T. Balafoutis, Konstantinos Vaiopoulos, George Kyriakarakos, Dimitris Manolakos, George Papadakis
Summary: This study conducts a review on energy use in EU livestock systems, finding that feed, housing, and manure management are the key areas for energy use. The existing data is fragmented with considerable data gaps, highlighting the need for a standardized methodology to measure energy use. This is crucial for achieving the sustainability targets of the EU.
APPLIED SCIENCES-BASEL
(2022)
Review
Green & Sustainable Science & Technology
Bas Paris, Foteini Vandorou, Athanasios T. Balafoutis, Konstantinos Vaiopoulos, George Kyriakarakos, Dimitris Manolakos, George Papadakis
Summary: This review summarizes the energy use in EU open-field agriculture, highlighting the significant contribution of fertilizer production to total energy inputs. It also points out the underreporting of energy use in EU agriculture and discusses the importance of fossil-energy-free technologies and strategies. The review emphasizes the need for detailed and standardized methodologies for energy use analysis in agricultural systems, as well as for further meta-analyses investigating energy use in agriculture.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Review
Chemistry, Multidisciplinary
Bas Paris, Foteini Vandorou, Athanasios T. Balafoutis, Konstantinos Vaiopoulos, George Kyriakarakos, Dimitris Manolakos, Papadakis George
Summary: This study reviews energy use in the EU greenhouse agriculture sector, finding that it is varied and primarily reliant on fossil fuels. High energy systems in northern Europe focus on climate control and heating/cooling, while low energy systems in southern Europe include heating, cooling, irrigation, lighting, fertilisers, and pesticides. Discussion is also provided on energy efficiency measures and renewable energy sources adoption in greenhouse production.
APPLIED SCIENCES-BASEL
(2022)
Article
Green & Sustainable Science & Technology
George Kyriakarakos, George Papadakis, Christos A. Karavitis
Summary: This paper reviews the status and potential solutions of renewable energy desalination for Greek islandic communities, covering technical solutions, energy needs, costs, current situation, potential solutions and proposing a methodology for addressing water needs. It also discusses how these options can be further deployed and their impacts on communities and the transition towards EU Green Deal goals.
Article
Thermodynamics
George Kosmadakis, Panagiotis Neofytou
Summary: This article examines an alternative waste heat recovery solution for ships, which relies on a reversible unit that switches between electricity production and steam generation. By utilizing the waste heat from the engine's cooling water, the reversible unit is able to increase the capacity factor. The study shows that the reversible unit outperforms individual solutions and achieves significant fuel savings.
Article
Energy & Fuels
George M. Kosmadakis, Dimitrios C. Rakopoulos, Constantine D. Rakopoulos
Summary: The effect of two mechanisms on the cyclic variability of a lean methane-hydrogen fueled SI engine was investigated using computational fluid dynamics (CFD) simulations. The first mechanism involves gas turbulent properties near the spark plug, while the second mechanism involves fuel mass variation per cycle. Linear regression and Monte Carlo-based approaches were used to analyze engine performance and emissions. The results showed that the first mechanism significantly affects the initial flame propagation, while the second mechanism affects the combustion process and CO emissions with high variability.
JOURNAL OF ENERGY ENGINEERING
(2023)
Article
Energy & Fuels
Marika Pilou, George Kosmadakis, George Meramveliotakis
Summary: This study describes an integrated numerical model for a renewable-energy-based system that meets a building's heating, cooling, and hot water needs. The model includes a vapor compression multi-source heat pump, PVT collectors, thermal energy storage, and water tanks. The model's performance is validated using measurements from a pilot operation in Athens and it has shown to accurately predict the building's energy system performance.
Article
Thermodynamics
Anastasios Skiadopoulos, George Kosmadakis, Steven Lecompte, Michel De Paepe, Dimitrios Manolakos
Summary: This paper presents a novel semi-empirical thermodynamic model for simulating two-phase expansion in twin-screw expanders. The model calculates the values of unknown parameters through a calibration-optimization process and performs simulations for various operating conditions. The results indicate that the vapor quality at the suction port of the expander is the main factor affecting its efficiency.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
