58 research outputs found
An ad hoc control system for managing the dynamic behaviour of a Brayton-based Carnot battery
No full textCarnot batteries (CBs) are considered a suitable grid-scale electricity storage technology to overcome the imbalance between power demand and production in a power grids with high renewable energy sources penetration.
In the literature, several studies propose different configurations, according to thermal storage technology as well as the charge/discharge cycle. Several investigations focus on the thermodynamics and optimisation of these systems.
However, the literature still lacks research dealing with CBs control systems and their dynamic behaviour during transient operations.
For this reason, in this work, an ad hoc dynamic model of a Brayton-based Carnot battery, along with its control system, has been developed in an OpenModelica environment.
The investigated configuration is the so-called Integrated Energy Storage System (I-ESS).
During the charge phase, a high temperature air flow, heated by electric heaters, releases heat to a packed-bed thermal energy storage.
The discharge system is basically a modified gas turbine in which the combustion chamber is replaced by thermal energy storage.
This work focusses on the discharge phase of the system, which is more complex and intrinsically characterised by dynamic behaviour.
To develop the CB’s control system, the authors started from the control system of a conventional gas turbine, which usually acts on two manipulated variables: the fuel mass flow rate and the compressor variable inlet guide vanes position (VIGV).
These variables are devoted to the regulation of the shaft speed and the turbine inlet temperature.
In CBs, on the other hand, the turbine inlet temperature is fixed by the storage temperature, and, since there is no fuel flow, the only manipulated variable remains the VIGV.
Therefore, a dedicated control system is needed.
The control system developed in this work consists of a proportional-integral-derivative (PI(D)) controller that receives as input the shaft rotational speed error and gives as output the signal for the VIGV regulation.
The developed controller was validated and properly tuned to achieve good results in terms of time domain specifications such as overshooting, undershooting, and settling time.
The optimal proportional gain, integral, and derivative time constants are 1.1, 3.5 and 1.1, respectively.
The results show that, given a power step function from 60% to 100%, a 10 MW Carnot battery can achieve a power settling time of approximately 1.2 to 3.3 seconds, with an overshoot of 2.0 to 4.6%.
The maximum shaft speed undershoot is 1.4%.
According to the results, a properly tuned PID controller allows Brayton-based Carnot batteries to have a dynamic response similar to that of a conventional gas turbine, with the additional value that the control system layout of a CB is much simpler and, therefore, easier to manage
An optimized approach to design Thermal Energy Storage Tank for electricity purposes
No full textIn recent years, electricity grids have experienced rapid penetration of power generation units based on variable and unpredictable renewable energy sources such as wind and solar. These sources are crucial for the transition to a more sustainable way of generating energy and therefore in achieving both the reduction of harmful emissions and the climate targets. However, high renewable penetration leads to some negative problems associated with the intermittent and fluctuating behaviour of such sources, such as a decrease in the quality of the energy transmitted through the electrical grid and an increase in the mismatch between power production and demand. To mitigate and/or compensate for such issues, it is extremely important to identify technologies capable of both storing and delivering the surplus of renewable electricity when the production from, for example, solar and wind, is null or insufficient to cover the demand of users. In this context, over the years, numerous energy storage technologies have been studied and developed. But many of them are characterised by significant geographical and morphological constraints, such as compressed air energy storage and pumped hydro energy storage, or suffer from low energy efficiency, such as flow batteries. Among emerging energy storage technologies, Carnot batteries (CBs) offer interesting performance without stringent geographic limitations, making them an attractive solution. Among CBs, integrated thermal energy storage systems (IT-ESS) seem to be a feasible and interesting solution because of their ease of installation and compatibility with existing power plants. Despite their potential, the most important component of this technology is the sensible heat thermal energy storage unit, designed as a packed bed. However, the literature lacks precise methods for designing this storage tank, a gap that motivated the authors to develop an innovative approach to determine the optimal size of the storage device. To this end, and with the aim of properly studying a complex system with the possibility of exchanging power with both users and the electrical grid and to account for the variability of renewable sources, the sizing procedure has been investigated through an optimisation algorithm developed in the Matlab environment. At the same time, the optimal storage device volume and the proper IT-ESS management strategy have been identified. The investigation performed considers real scenarios, analysing real users and describing in an accurate way the intermittent behaviour of renewable sources
AN INNOVATIVE TOOL FOR OPTIMIZING THE ENERGY HUB OF LARGE BUILDINGS: THE CASE STUDY OF A NEW HOSPITAL IN NORTHERN ITALY
No full textThe challenge of achieving net zero emissions by 2050 necessitates to drastically reduce the energy consumption of the building sector, which alone contributes for almost 40% of the anthropic CO_2 emissions. In recent years, growing attention has been paid to the minimization of costs and emissions of large buildings by optimizing the design and operation of their energy systems. Most of the works available in the literature consider a limited set of technologies to meet only the electrical and heating demands.
In this work an innovative model is developed for the optimization of the energy hub of a hospital, characterized by 5 distinct energy demands: Electrical, Heating, Cooling, Steam and Sanitary Hot Water. To satisfy such demands, the proposed model considers a large set of technologies including cogeneration units, absorbers, reversible and multipurpose heat pumps. The tool consists of two sequential Python codes for the size optimization and the operation optimization, respectively. The first code defines the size of each technology considering the energy needs of four representative days obtained using the k-medoid method, with two extreme days added to ensure load supply. A preliminary investigation demonstrated that this clustering technique leads to an overestimation in the objective function of less than 3%, compared to a 365-days simulation. Therefore, the computational time is drastically reduced with a small impact on the results accuracy. The optimal sizes obtained from the first part of the model are used as input for the second code, which defines the optimal operation of the system throughout the year. The optimization problems are solved using the Python extension of Gurobi, a software that allows for the assessment of MIQP and MILP models by exploiting the branch and bound method. Two different objective functions are considered: total annual costs and CO_2 emissions. The first code results show that, according to the considered objective function, a reduction of 14.4% in the annual costs or a reduction of 12.36% in the CO_2 emissions can be reached with respect to a non-optimized reference configuration, with a difference between the two optimized solutions of 20.60\% in the CO_2 emissions and of 42.07% in the total costs. Between the two solutions, the one provided by the economical optimization is chosen for the entire year simulation. Once the technologies to be used were selected, the simulation of the model was performed resulting in a cost increase with respect to the first code of 4.44 %, and an increase of CO_2 emissions of 4.5%
Optimization and assessment method to approach industrial site decarbonization: A case study of a light industry
No full textThe industrial sector includes a wide range of industries and processes for which a single approach or universal strategies for decarbonization can hardly be identified. In general, the most efficient way to decarbonize building sites consists of two phases: (i) reduce the energy demand and (ii) replace the fossil-based power generation units with renewable energy sources, possibly working on the management of HVAC systems to reduce the required peak power. Literature provides general rules and schemes, but no specific works on the energy retrofit of industrial buildings have been found in literature so far. The present study investigates an existing industrial district, using dynamic energy models of buildings tuned with the current conditions and compared with seven decarbonization scenarios. A neutral water loop exchanging heat with the ground has been studied, representing a widely replicable solution due to the higher heat exchange efficiency and the modular installation, which can be expanded within the site. The significant energy savings (28%) and CO2 emission reduction (up to 70%) obtained are representative of the potential achievable for many industrial sites in mild European climates, where decarbonization should achieve optimal cost-benefit results while minimizing the impact on the production through modular approaches
Correction to: Ostomy closure rate during COVID-19 pandemic: an Italian multicentre observational study (Updates in Surgery, (2022), 74, 3, (1017-1025), 10.1007/s13304-022-01274-w)
No full textWhile typesetting the article the Collaborators were not included in the proofs. The collaborators names are provided below: DOC Collaborative Group: Laura Agostinelli, Ferdinando Agresta, Gabriele Anania, Laura Antolino, Pietro Anoldo, Emanuele Botteri, Umberto Bracale, Fabio Carbone, Massimo Carlini, Francesco Maria Carrano, Giorgia Casadei, Diego Coletta, Francesco Crafa, Nicola de’Angelis, Paolo Delrio, Giovanni Domenico De Palma, Marcello Di Martino, Ugo Elmore, Lorenzo Gozzini, Michele Grieco, Giovanni Battista Levi Sandri, Edelweiss Licitra, Andrea Lucchi, Marco Massani, Riccardo Memeo, Marco Milone, Dario Oppici, Monica Ortenzi, Alberto Patriti, Francesca Pecchini, Roberto Peltrini, Micaela Piccoli, Adolfo Pisanu, Mauro Podda, Gilberto Poggioli, Maria Chiara Ranucci, Daniela Rega, Riccardo Rosati, Francesco Roscio, Matteo Rottoli, Roberto Santoro, Alberto Sartori, Antonino Spinelli, Serafino Vanella, Giovanni Vennarecci, Nereo Vettoretto. The original article has been corrected
Correction to: Safety and efficacy of COVID-19 vaccines in patients on dialysis: a multicentre cohort study in Italy
No full textThe COVIDVaxDia Study Group in html which currently reads Francesca Menniti-Ippolito, Roberto Da Cas, Flavia Chiarotti, Massimo Fabiani, Giuseppe Traversa, Piergiorgio Messa, Alfonso Mele, Salvatore De Masi, Francesca Colavita, Concetta Castilletti, Carmine Zoccali, Aldo Pietro Maggioni, Andrea Lorimer, Martina Ceseri, Ester Baldini, Francesca Bianchini, Laura Sarti, Giovanni Baglio, Andrea Mariano and Eva Alessi. It should read as: Francesca Menniti-Ippolito, Roberto Da Cas, Flavia Chiarotti, Massimo Fabiani, Giuseppe Traversa, Piergiorgio Messa, Alfonso Mele, Salvatore De Masi, Francesca Colavita, Concetta Castilletti, Carmine Zoccali, Aldo Pietro Maggioni, Andrea Lorimer, Martina Ceseri, Ester Baldini, Francesca Bianchini, Laura Sarti, Giovanni Baglio, Andrea Mariano & Eva Alessi, Lorenzo Di Liberato, Luigi Amoroso, Nicola Spetrino, Milva Di Giovanni, Carlo Sapio, Irma Figlia, Roberto Pititto, Teresa Papalia, Rosita Greco, Francesca Leone, Francesco Maria D’Agostino, Mariangela Campolo, Maria Rosa La Gamba, Francesca Mallamaci, Vincenzo Panuccio, Giovanna Parlongo, Giuseppe Natale, Domenico Tramontana, Ivania Maria Figliano, Santo Vitiello, Anna Maria Frangiosa, Domenico Caserta, Pasqualina Acconcia, Nunzia Paudice, Alfonso De Maio, Salvatore Cascone, Marilina Siani, Mario Cioffi, Nataliya Romanyuk, Franca Pagnano, Antonio De Donato, Ersilia Satta, Alessandra Perna, Francesco Trepiccione, Alessandro Cerrone, Gianluca Garofalo, Giancarlo Marinelli, Roberta D’Amato, Enrico De Felice, Alfredo Vacca, Salvatore Coppola, Vincenzo Cuomo, Maria Palma Iavarone, Annalisa Ciotola, Vincenzo Puglia, Pio Granato, Carla Lamberti, Giorgio Capasso, Domenico Bonanno, Marco Ventre, Veronica Amendola, Fabio Cappabianca, Elena Mancini, Davide Ricci, Daniela Cecilia Cannarile, Roberta Benevento, Bianca Perciaccante, Alda Storari, Yuri Battaglia, Giovanni Piva, Giovanni Mosconi, Alessandra Spazzoli, Paolo Ferdinando Bruno, Katia Ambri, Barbara Veterani, Sara Signorotti, Marcora Mandreoli, Renato Mario Rapanà, Maria Teresa Benedetto, Laura Patregnani, Maddalena Zambelli, Gaetano Alfano, Mariacristina Gregorini, Silvia Mattei, Francesca Iannuzzella, Elena Pelizzaro, Luca Camparini, Giuseppe Battaglino, Dino Romanini, Antonio Irlando, Lojze Celik, Giuseppa Natale, Maria Cristina Torre, Ilaria Umbro, Nicola Pirozzi, Loredana Fazzari, Lucia Pantano, Antonio Paone, Marco Galliani, Veronica Baglio, Eleonora Moscaritolo, Sabrina Fierimonte, Maria De Cristofaro, Elena Nebuloso, Paolo Menè, Francesca Romana Festuccia, Giulia Talarico, Claudia Fofi, Maria Elena Bracaccia, Ernesto Anselmo Cioffi, Fabio Mazza, Pasquale Polito, David Micarelli, Roberto Addesse, Lida Tartaglione, Sandro Feriozzi, Francesca Romana Della Rovere, Natalia Chipilova, Micol Manzuoli, Paolo Sacco, Francesca Ansaldo, Chiara Bottaro, Sonia Marre, Francesc Viazzi, Valeria Falqui, Novella Conti, Angelica Parodi, Valentina Zanetti, Francesca Cappadona, Andrea Speciale, Giancarlo Mancuso, Monica Repetto, Emanuela Chiara Vigo, Cairo Montenotte, Anna Maria Murgia, Piero Ruggenenti, Patrizia Ondei, Carmela Giuseppina Condemi, Sivia Bernardi, Francesco Scolari, Paola Gaggia, Federico Alberico, Chiara Manenti, Brunella Valzorio, Corrado Camerini, Agnese Gallico, Michela Tonoli, Federico Daffara, Roberto Zubbani, Simona Guerini, Mattia Zappa, Nicole Zambetti, Alessandra Dalla Gassa, Paola Baldan, Luca Fraizzoli, Sergio Bisegna, Nicola Palmieri, Marco Petrilli, Giusy Mandanici, Francesca Serena Stefani, Valeria Ogliari, Cristina Tantardini, Fabio Malberti, Paola Pecchini, Vincenzo La Milia, Carlo Maria Guastoni, Annalisa Neri, Marina Cornacchiari, Marco Farina, Francesco Barbisoni, Milena Maggio, Mario Cozzolino, Matthias Cassia, Michela Frittoli, Lorenza Magagnoli, Rossella De Leonardis, Roberta Casazza, Simone Vettoretti, Emanuele Grimaldi, Matteo Abinti, Francesca Maria Ida Carminati, Silvia Giuliani, Matteo Benedetti, Nicholas Delfrate, Elisa Colombo, Angela Cervesato, Enrico Eugenio Minetti, Alberto Montoli, Chiara Brunati, Valerae Li Bergolis, Maurizio Galllieni, Cristina Airaghi, Monique Buskermolen, Laura Cosmai, Maria Antonietta Orani, Cristina De Salvo, Giuseppe Vezzoli, Giorgio Slaviero, Chiara Lanzani, Federico Pieruzzi, Gina Contaldo, Barbara Trezzi, Teresa Rampino, Fabrizio Grosjean, Paola Borille, Ciro Esposito, Giuseppe Sileno, Marta Arazzi, Gianvincenzo Melfa, Mariagiulia Tettamanti, Anna Tosetti, Marco D’Amico, Maria Giulia Magatti, Silvia Peiti, Luciano Pedrini, Annalisa Feliciani, Elena Pezzini, Silvio Volmer Bertoli, Daniele Ciurlino, Silvia Tedoldi, Vania Prettico, Giulia Maria Magni, Antonietta Gazo, Maurizio Nai, Silvia Muciaccia, Graziana Battini, Lino Merlino, Paola Casanova, Federica Lencia, Maddalena Ricci, Andrea Ranghino, Mauro Valente, Carolina Finale, Eleonora Guerrini, Marta Canonici, Stefano Santarelli, Rosa Maria Agostinelli, Marina Di Luca, Mauro Martello, Cristina Silvestri, Veronica Bertuzzi, Assunta Cardillo, Valentina Nastasi, Sara Belcastro, Marco Manganaro, Emanuele Luigi Parodi, Valentina Vaccaro, Antonella Giolito, Stefano Cusinato, Michele Battista, Elena Ragazzoni, Paola Marcella Carpani, Emanuele Stramignoni, Silvana Savoldi, Guido Martina, Chiara Deagostini, Marica Magnetti, Stefania Bussolino, Federica Ventrella, Sonia Santi, Marita Marengo, Daniela Falconi, Ilaria Serra, Luca Besso, Davide Diena, Doriana Chiari Notti, Paola David, Luciana Gravellone, Corrado Vitale, Silvia Berutti, Silvia Ganci, Federica Neve Vigotti, Giulio Cesano, Maurizio Borzumati, Patrizia Bio, Stefania Gioira, Oliviero Filiberti, fabiola Pagani, Simonetta Ottone, Carlo Lomonte, Vincenzo Montinaro, Vito Pepe, Elisabetta Manno, Salvatore Di Paolo, Luigi Natalicchio, Carmela Gallo, Francesca pansini, Rossella Varvara, Filomena D’Elia, NIcola Coviello, Concetta Prisciandaro, Lucia Vernò, Fernanda Misceo, Pierfelice Zazzera, Antonella Matrella, Loreto Gesualdo, Anna Maria Di Palma, Virginia Pronzo, Federica Cassone, Salvatore Di Paolo, Tiziana Piccolo, Dora Porcelluzzi, Antonella Di Franco, Mario Giannetto, Chiara Villani, Luigi Vernaglione, Angelo Specchio, Laura Stoico, Giovanni Stallone, Vincenzo Losappio, Barbara Infante, Luigi Morrone, Anna Lisa Marangi, Angela Rodio, Christian D’Altri, Paolo Venerito, Francesca Cianciotta, Filippo Aucella, Gaetano Ferrara, Anna Rachele Nardella, Luigi Francesco Pio Morrone, Maria Grazia Corallo, Giuseppina D’Ettorre, Francesco Caccetta, Davide Gianfreda, Antonello Pani, Gianfranca Cabiddu, Stefania Caria, Maria Maddalena Romano, Ciro Adamo, Giovanni Giorgio Battaglia, Barbara Pocorobba, Emanuela Prencipe, Margherita Saraceno, Luana Scuderi, Salvatore Randone, Francesca Bruno, Rossella Rita Marchese, Antonio Granata, Daniela Puliatti, Carmelita Marcantoni, Luca Zanoli, Ambra D’anca, Domenico Santoro, Guido Gembillo, Alfio Eduardo Giuffrida, Vincenzo Labbozzetta, Angelo Tralongo, Gioacchino Li Cavoli, Carmela Zaggarigo, Paolo Conti, Sofia Giovannini, Silvia Farsetti, Pietro Claudio Giovanni Dattolo, Aris Tsalouchos, Stefano Michelassi, Marco Gallo, Irene Bandor, Nadia Sami, Daniela Riccomi, Lorena Traversari, Maria Grazia Tabbi, Maria Luisa Bonincontro, Vera Bonell, Giuliano Brunori, Diana Zarantonello, Alessandro Laudon, Antonio Selvi, Stefania Santoni, Davide Massimiani, Davide Rossi, Lorenzo Calò, Barbara Rossi, Giuseppe Scaparrotta, Fulvio Fiorini, Valentina Iacono, Carlo Rugiu, Monica Slaviero, Maurizio Nordio, Riccarda Maria Puggia, Adriana Caberlotto, Flavio Scanferla, Vincenzo Casoria, Federica Gramegna, Gina Meneghel, Ilenia Filippi, Anna Giacomini, Claudio Ronco, Anna Giuliani, Sabrina Milan Manani, Monica Zanella
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