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Born in Milan (Italy) in 1971. MS in Mechanical Engineering in 1998 and PhD in Energetics at Politecnico di Milano in 2001. Actually is Associate Professor of “Power Production from Renewable Energy Sources”. Since 1999 works as a researcher at the Department of Energy of Politecnico di Milano in the field of high efficiency power plants, supercritical CO2 cycles, ORC, cogeneration and concentrating solar power plants. He is author of many papers in the same fields.
In the near future, due to the growing share of variable renewable energy in the electricity mix and the lack of large-scale electricity storage, coal plants will have to shift their role from base-load operation to providing fluctuating back-up power. However, current coal power plants, based on steam Rankine cycle, are not optimized for flexible part-load operation, resulting in an intrinsic inadequacy for fast load variations. The founding idea of the H2020 sCO2-Flex project is to improve the flexibility of pulverized coal power plants by adopting supercritical CO2 Brayton power cycles. Despite the extensive literature about the design of sCO2 plants, there is still limited discussion about the strategies to be implemented to maximize system efficiency during part-load operation. This paper aims to provide deeper insight about the potential of sCO2 power plants based on recompressed cycle with high-temperature recuperator (HTR) bypass configuration for small modular coal power plants (25 MWel). Analysis focuses on both design and part-load operation providing a preliminary sizing of each component and comparing different operating strategies. Results demonstrate that sCO2 coal power plants can achieve competitive efficiency in both nominal and part-load operation thanks to the progressive increase of heat exchangers effectiveness. Moreover, they can be operated down to 20% electric load increasing power range of coal plants. Finally, the possibility to optimize the cycle minimum pressure ensures a safe operation of the compressor far from the surge line and to increase the performance at low load.
Dario Alfani; Marco Astolfi; Marco Binotti; Paolo Silva. Part-Load Strategy Definition and Preliminary Annual Simulation for Small Size sCO2-Based Pulverized Coal Power Plant. Journal of Engineering for Gas Turbines and Power 2021, 143, 1 .
AMA StyleDario Alfani, Marco Astolfi, Marco Binotti, Paolo Silva. Part-Load Strategy Definition and Preliminary Annual Simulation for Small Size sCO2-Based Pulverized Coal Power Plant. Journal of Engineering for Gas Turbines and Power. 2021; 143 (9):1.
Chicago/Turabian StyleDario Alfani; Marco Astolfi; Marco Binotti; Paolo Silva. 2021. "Part-Load Strategy Definition and Preliminary Annual Simulation for Small Size sCO2-Based Pulverized Coal Power Plant." Journal of Engineering for Gas Turbines and Power 143, no. 9: 1.
Dario Alfani; Marco Astolfi; Marco Binotti; Paolo Silva. Part Load Strategy Definition and Annual Simulation for Small Size sCO2 Based Pulverized Coal Power Plant. 2021, 1 .
AMA StyleDario Alfani, Marco Astolfi, Marco Binotti, Paolo Silva. Part Load Strategy Definition and Annual Simulation for Small Size sCO2 Based Pulverized Coal Power Plant. . 2021; ():1.
Chicago/Turabian StyleDario Alfani; Marco Astolfi; Marco Binotti; Paolo Silva. 2021. "Part Load Strategy Definition and Annual Simulation for Small Size sCO2 Based Pulverized Coal Power Plant." , no. : 1.
Stirling units are a viable option for micro-cogeneration applications, but they operate often with multiple daily startups and shutdowns due to the variability of load profiles. This work focused on the experimental and numerical study of a small-size commercial Stirling unit when subjected to cycling operations. First, experimental data about energy flows and emissions were collected during on–off operations. Second, these data were utilized to tune an in-house code for the economic optimization of cogeneration plant scheduling. Lastly, the tuned code was applied to a case study of a residential flat in Northern Italy during a typical winter day to investigate the optimal scheduling of the Stirling unit equipped with a thermal storage tank of diverse sizes. Experimentally, the Stirling unit showed an integrated electric efficiency of 8.9% (8.0%) and thermal efficiency of 91.0% (82.2%), referred to as the fuel lower and, between parenthesis, higher heating value during the on–off cycling test, while emissions showed peaks in NOx and CO up to 100 ppm but shorter than a minute. Numerically, predictions indicated that considering the on–off effects, the optimized operating strategy led to a great reduction of daily startups, with a number lower than 10 per day due to an optimal thermal storage size of 4 kWh. Ultimately, the primary energy saving was 12% and the daily operational cost was 2.9 €/day.
Gianluca Valenti; Aldo Bischi; Stefano Campanari; Paolo Silva; Antonino Ravidà; Ennio Macchi. Experimental and Numerical Study of a Microcogeneration Stirling Unit Under On–Off Cycling Operation. Energies 2021, 14, 801 .
AMA StyleGianluca Valenti, Aldo Bischi, Stefano Campanari, Paolo Silva, Antonino Ravidà, Ennio Macchi. Experimental and Numerical Study of a Microcogeneration Stirling Unit Under On–Off Cycling Operation. Energies. 2021; 14 (4):801.
Chicago/Turabian StyleGianluca Valenti; Aldo Bischi; Stefano Campanari; Paolo Silva; Antonino Ravidà; Ennio Macchi. 2021. "Experimental and Numerical Study of a Microcogeneration Stirling Unit Under On–Off Cycling Operation." Energies 14, no. 4: 801.
A key approach to large renewable power management is based on implementing storage technologies, including batteries, power-to-gas, and compressed air energy storage (CAES). This work presents the preliminary design and performance assessment of an innovative type of CAES, based on underwater compressed air energy storage (UW-CAES) volumes and intended for installation in the proximity of deep-water seas or lakes. The UW-CAES works with constant hydrostatic pressure storage and variable volumes. The proposed system is adiabatic, not using any fuel to increase the air temperature before expansion; a sufficient turbine inlet temperature (TIT) is instead obtained through a thermal energy storage (TES) system which recovers the compression heat. The system includes (i) a set of turbomachines (modular multistage compressor, with partial intercooling; expansion turbine); (ii) a TES system with different temperature levels designed to recover a large fraction of the compression heat, allowing the subsequent heating of air prior to the expansion phase; (iii) an underwater modular compressed air storage, conceived as a network of rigid but open tanks lying on the seabed and allowing a variable-volume and constant pressure operation. The compressor operates at variable loads, following an oscillating renewable power input, according to strategies oriented to improve the overall system dispatchability; the expander can be designed to work either at full load, thanks to the stability of the air flowrate and of the TIT guaranteed by the thermal storage, or at variable load. This paper first discusses in detail the sizing and off-design characterization of the overall system; then it simulates a case study where the UW-CAES is coupled to a wind farm for peak shaving and dispatchability enhancement, evaluating the impact of a realistic power input on performances and plant flexibility. Although the assessment shall be considered preliminary, it is shown that round-trip efficiency (RTE) in the range of 75–80% can be obtained depending on the compressor section configuration, making the UW-CAES a promising technology compared to electrochemical and pumped-hydrostorage systems. The technology is also applied to perform peak-shaving of the electricity production from an off-shore wind farm; annual simulations, based on realistic wind data and considering part-load operation, result in global RTE around 75% with a 10–15% reduction in the average unplanned energy injection in the electric grid. The investigated case study provides an example of the potential of this system in providing power output peak shaving when coupled with an intermittent and nonpredictable energy source.
Marco Astolfi; Giulio Guandalini; Marco Belloli; Adriano Hirn; Paolo Silva; Stefano Campanari. Preliminary Design and Performance Assessment of an Underwater Compressed Air Energy Storage System for Wind Power Balancing. Journal of Engineering for Gas Turbines and Power 2020, 142, 1 .
AMA StyleMarco Astolfi, Giulio Guandalini, Marco Belloli, Adriano Hirn, Paolo Silva, Stefano Campanari. Preliminary Design and Performance Assessment of an Underwater Compressed Air Energy Storage System for Wind Power Balancing. Journal of Engineering for Gas Turbines and Power. 2020; 142 (9):1.
Chicago/Turabian StyleMarco Astolfi; Giulio Guandalini; Marco Belloli; Adriano Hirn; Paolo Silva; Stefano Campanari. 2020. "Preliminary Design and Performance Assessment of an Underwater Compressed Air Energy Storage System for Wind Power Balancing." Journal of Engineering for Gas Turbines and Power 142, no. 9: 1.
Paolo Silva; Aldo Bischi; Marco Lamberti; Stefano Campanari; Ennio Macchi; Danilo Tacchinardi. Trigenerative solution for natural gas compressor stations: A north Italian test case. Energy 2019, 184, 129 -140.
AMA StylePaolo Silva, Aldo Bischi, Marco Lamberti, Stefano Campanari, Ennio Macchi, Danilo Tacchinardi. Trigenerative solution for natural gas compressor stations: A north Italian test case. Energy. 2019; 184 ():129-140.
Chicago/Turabian StylePaolo Silva; Aldo Bischi; Marco Lamberti; Stefano Campanari; Ennio Macchi; Danilo Tacchinardi. 2019. "Trigenerative solution for natural gas compressor stations: A north Italian test case." Energy 184, no. : 129-140.
Aldo Bischi; Leonardo Taccari; Emanuele Martelli; Edoardo Amaldi; Giampaolo Manzolini; Paolo Silva; Stefano Campanari; Ennio Macchi. A rolling-horizon optimization algorithm for the long term operational scheduling of cogeneration systems. Energy 2019, 184, 73 -90.
AMA StyleAldo Bischi, Leonardo Taccari, Emanuele Martelli, Edoardo Amaldi, Giampaolo Manzolini, Paolo Silva, Stefano Campanari, Ennio Macchi. A rolling-horizon optimization algorithm for the long term operational scheduling of cogeneration systems. Energy. 2019; 184 ():73-90.
Chicago/Turabian StyleAldo Bischi; Leonardo Taccari; Emanuele Martelli; Edoardo Amaldi; Giampaolo Manzolini; Paolo Silva; Stefano Campanari; Ennio Macchi. 2019. "A rolling-horizon optimization algorithm for the long term operational scheduling of cogeneration systems." Energy 184, no. : 73-90.
A key approach to large renewable power management is based on implementing storage technologies, including batteries, power-to-gas and compressed air energy storage (CAES). This work presents the preliminary design and performance assessment of an innovative type of CAES, based on underwater storage volumes (UW-CAES) and intended for installation in the proximity of deep water seas or lakes. The UW-CAES works with constant hydrostatic pressure storage and variable volumes. The proposed system is adiabatic, not using any fuel to increase the air temperature before expansion; a sufficient TIT is instead obtained through a thermal energy storage system which recovers the compression heat. The system includes (i) a set of turbomachines (modular multi-stage compressor, with partial intercooling; expansion turbine); (ii) a thermal energy storage (TES) system with different temperature levels designed to recover a large fraction of the compression heat, allowing the subsequent heating of air prior to the expansion phase; (iii) an underwater modular compressed air storage, conceived as a network of rigid but open tanks lying on the seabed and allowing a variable-volume and constant pressure operation. The compressor operates at variable loads, following an oscillating renewable power input, according to strategies oriented to improve the overall system dispatchability; the expander can be designed to work either at full load, thanks to the stability of the air flow rate and of the TIT guaranteed by the thermal storage, or at variable load. The paper first discusses in detail the sizing and off-design characterization of the overall system; it is then simulated a case study where the UW-CAES is coupled to a wind farm for peak shaving and dispatchability enhancement, evaluating the impact of a realistic power input on performances and plant flexibility. Although the assessment shall be considered preliminary, it is shown that round trip efficiency in the range of 75%–80% can be obtained depending on the compressor section configuration; making the UW-CAES a promising technology compared to electrochemical and pumped-hydro storage systems. The technology is also applied to perform peak-shaving of the electricity production from a wind park; annual simulations considering part load operation result in global round trip efficiency around 75% with a 10 to 15% reduction in the average unplanned energy injection in the electric grid. The investigated case study provides an example of the potential of this system in providing power output peak shaving when coupled with an intermittent and non-predictable energy source.
Marco Astolfi; Giulio Guandalini; Marco Belloli; Adriano Hirn; Paolo Silva; Stefano Campanari. Preliminary Design and Performance Assessment of an Underwater CAES System (UW-CAES) for Wind Power Balancing. Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems 2019, 1 .
AMA StyleMarco Astolfi, Giulio Guandalini, Marco Belloli, Adriano Hirn, Paolo Silva, Stefano Campanari. Preliminary Design and Performance Assessment of an Underwater CAES System (UW-CAES) for Wind Power Balancing. Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems. 2019; ():1.
Chicago/Turabian StyleMarco Astolfi; Giulio Guandalini; Marco Belloli; Adriano Hirn; Paolo Silva; Stefano Campanari. 2019. "Preliminary Design and Performance Assessment of an Underwater CAES System (UW-CAES) for Wind Power Balancing." Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems , no. : 1.
Coal-fired power plants play a major role in large scale power generation by producing about 41% and 25% of the electricity in the world and in the EU, respectively. In the context of EU’s climate and energy policy (EU Reference Scenario 2016) and with a view to decarbonizing the electricity sector, the share of non-programmable renewable energies will soar in future years both in and outside the EU. As result, the role of fossil-fuel plants including coal-fired plants is expected to evolve, leading to a paradigm shift for their design and operation, which will move from constant base-load operation to increasingly variable power production for the integration of intermittent renewable energy sources. In the present work, developed within the EU project sCO2-Flex, the design and analysis of a coal-fired plant implementing a 100 MWel recompressed sCO2 power cycle is assessed, with particular focus on the trade-off between system performance and flexibility. The effects of the different design assumptions on the overall components’ sizing and system performance are investigated and a methodology to quantify the thermal inertia and the system flexibility based on the calculation of heat exchangers surfaces, volumes and masses (boiler tube walls and convective pass, recuperators and gas cooler heat rejection unit) is then presented. Finally, the cycle optimization is repeated with the aim to find the optimal trade-off between plant efficiency and thermal inertia, eventually providing a number of promising designs for next generation sCO2 fossil fuel power plants.
Dario Alfani; Marco Astolfi; Marco Binotti; Stefano Campanari; Francesco Casella; Paolo Silva. Multi Objective Optimization of Flexible Supercritical CO2 Coal-Fired Power Plants. Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems 2019, 1 .
AMA StyleDario Alfani, Marco Astolfi, Marco Binotti, Stefano Campanari, Francesco Casella, Paolo Silva. Multi Objective Optimization of Flexible Supercritical CO2 Coal-Fired Power Plants. Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems. 2019; ():1.
Chicago/Turabian StyleDario Alfani; Marco Astolfi; Marco Binotti; Stefano Campanari; Francesco Casella; Paolo Silva. 2019. "Multi Objective Optimization of Flexible Supercritical CO2 Coal-Fired Power Plants." Volume 3: Coal, Biomass, Hydrogen, and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems , no. : 1.
This work discusses a preliminary thermodynamic assessment of three different supercritical CO2(sCO2) power cycles applied to a high temperature solar tower system, with maximum temperatures up to 800 °C. The thermal power is transferred from the solar receiver to the power block through KCl-MgCl2molten salts as heat transfer fluid, therefore an indirect cycle configuration is considered assuming a surrounded field as the one of Gemasolar plant. The most promising cycle configuration in terms of solar-to-electric efficiency is selected, optimizing the cycle turbine inlet temperature to achieve the best compromise between cycle and receiver performance: the highest efficiency at design conditions is achieved by the Recompression with Main Compression Intercooling (RMCI) configuration with a solar to electric efficiency of 24.5% and a maximum temperature of 750 °C. The yearly energy yield of the proposed power plant is estimated with a simplified approach and results in the range of 18.4%: the performance decay from design to average yearly conditions is mostly due to the optical and thermal efficiencies reduction (â\u88\u9210.8% and â\u88\u9216.4%, respectively)
Marco Binotti; Marco Astolfi; Stefano Campanari; Giampaolo Manzolini; Paolo Silva. Preliminary assessment of sCO2 cycles for power generation in CSP solar tower plants. Applied Energy 2017, 204, 1007 -1017.
AMA StyleMarco Binotti, Marco Astolfi, Stefano Campanari, Giampaolo Manzolini, Paolo Silva. Preliminary assessment of sCO2 cycles for power generation in CSP solar tower plants. Applied Energy. 2017; 204 ():1007-1017.
Chicago/Turabian StyleMarco Binotti; Marco Astolfi; Stefano Campanari; Giampaolo Manzolini; Paolo Silva. 2017. "Preliminary assessment of sCO2 cycles for power generation in CSP solar tower plants." Applied Energy 204, no. : 1007-1017.
Marco Astolfi; Simone Mazzola; Paolo Silva; Ennio Macchi. A synergic integration of desalination and solar energy systems in stand-alone microgrids. Desalination 2017, 419, 169 -180.
AMA StyleMarco Astolfi, Simone Mazzola, Paolo Silva, Ennio Macchi. A synergic integration of desalination and solar energy systems in stand-alone microgrids. Desalination. 2017; 419 ():169-180.
Chicago/Turabian StyleMarco Astolfi; Simone Mazzola; Paolo Silva; Ennio Macchi. 2017. "A synergic integration of desalination and solar energy systems in stand-alone microgrids." Desalination 419, no. : 169-180.
Sonia L. Gómez-Aláez; Veronica Brizzi; Dario Alfani; Paolo Silva; Andrea Giostri; Marco Astolfi. Off-design study of a waste heat recovery ORC module in gas pipelines recompression station. Energy Procedia 2017, 129, 567 -574.
AMA StyleSonia L. Gómez-Aláez, Veronica Brizzi, Dario Alfani, Paolo Silva, Andrea Giostri, Marco Astolfi. Off-design study of a waste heat recovery ORC module in gas pipelines recompression station. Energy Procedia. 2017; 129 ():567-574.
Chicago/Turabian StyleSonia L. Gómez-Aláez; Veronica Brizzi; Dario Alfani; Paolo Silva; Andrea Giostri; Marco Astolfi. 2017. "Off-design study of a waste heat recovery ORC module in gas pipelines recompression station." Energy Procedia 129, no. : 567-574.
Marco Binotti; Marco Astolfi; Stefano Campanari; Giampaolo Manzolini; Paolo Silva. Preliminary Assessment of sCO 2 Power Cycles for Application to CSP Solar Tower Plants. Energy Procedia 2017, 105, 1116 -1122.
AMA StyleMarco Binotti, Marco Astolfi, Stefano Campanari, Giampaolo Manzolini, Paolo Silva. Preliminary Assessment of sCO 2 Power Cycles for Application to CSP Solar Tower Plants. Energy Procedia. 2017; 105 ():1116-1122.
Chicago/Turabian StyleMarco Binotti; Marco Astolfi; Stefano Campanari; Giampaolo Manzolini; Paolo Silva. 2017. "Preliminary Assessment of sCO 2 Power Cycles for Application to CSP Solar Tower Plants." Energy Procedia 105, no. : 1116-1122.
Cristina Elsido; Aldo Bischi; Paolo Silva; Emanuele Martelli. Two-stage MINLP algorithm for the optimal synthesis and design of networks of CHP units. Energy 2017, 121, 403 -426.
AMA StyleCristina Elsido, Aldo Bischi, Paolo Silva, Emanuele Martelli. Two-stage MINLP algorithm for the optimal synthesis and design of networks of CHP units. Energy. 2017; 121 ():403-426.
Chicago/Turabian StyleCristina Elsido; Aldo Bischi; Paolo Silva; Emanuele Martelli. 2017. "Two-stage MINLP algorithm for the optimal synthesis and design of networks of CHP units." Energy 121, no. : 403-426.
Caterina Fella; Paolo Silva; Cesar Alejandro Isaza Roldan. Performance analysis of a Solar-Powered Air-Conditioning System Using Absorption Refrigeration Cycle and High Efficiency Cooling Technologies. Proceedings of SWC2017/SHC2017 2017, 1 .
AMA StyleCaterina Fella, Paolo Silva, Cesar Alejandro Isaza Roldan. Performance analysis of a Solar-Powered Air-Conditioning System Using Absorption Refrigeration Cycle and High Efficiency Cooling Technologies. Proceedings of SWC2017/SHC2017. 2017; ():1.
Chicago/Turabian StyleCaterina Fella; Paolo Silva; Cesar Alejandro Isaza Roldan. 2017. "Performance analysis of a Solar-Powered Air-Conditioning System Using Absorption Refrigeration Cycle and High Efficiency Cooling Technologies." Proceedings of SWC2017/SHC2017 , no. : 1.
An historic pact on Climate Change signed by 195 countries during the last COP 21 in Paris 2015 established elements to deal with emission reductions and global temperature rise, which will take effect by 2020. Therefore, renewable energy sources are essential to reach these new targets, like the world area's abundant solar resources that can be developed in order to contribute partially to the fossil fuel reduction, increasing the energy efficiency of O&G plants and reducing the emissions level at the same time. Solar PV (photovoltaic) is the most widely used solar energy technology to date and secondly, CSP (Concentrated Solar Power). While PV converts sunlight directly into electricity by using panel arrays based on semiconductor materials, the CSP make use of mirrors to concentrate the sun's energy and produce steam that can be used in the oil and gas industry in different ways: To drive steam turbines and produce the electrical power to supplement the oil and gas facilities demand.For thermal technologies in enhanced oil recovery systems or generally for plant process units steam use. All of the aforementioned CSP applications have the possibility to add thermal energy storage systems needed to overcome night time or for topping off during non-ideal solar conditions. Nowadays the photovoltaic cells have evolved technologically being very affordable with decreasing price trends and an increasing interest in standalone application at medium to large-scale capacity, nevertheless the CSP is shyly appearing in the oil and gas industry in specific geographical areas basing its attractiveness as a source of steam generation. The present paper refers to a case study of a combined-cycle power plant which benefits of the integration with a solar field (Integrated Solar Combined Cycle – ISCC) for oil and gas production facilities use sited in the North Africa region. This geographical area offers appropriate solar DNI (Direct Normal Irradiance) for CSP technologies. The selected configuration for this case, exploit the CSP heat in the same heat recovery steam generator (HRSG) of the combined cycle. Solar heat is integrated at the evaporation section, with an efficient heat exchange coming from the CSP system. In this study, it is presented a fuel saving configuration, in which constant power is produced. Therefore gas turbine electric load decreases up to 80% and the remaining electricity is produced in the steam cycle exploiting the heat coming from the solar field, which thermal load is decided as an overall compromise solution for the CSP field size. Results from the life cycle cost analysis showed that investment payback in order to be inside project operational life limits is largely driven from two market variables remaining a barrier: fuel gas price and CO2 shadow price; other limitation that might be an issue is water scarcity in the area for steam cycle or make up and also any permitting for connection to the grid unless the plant will be operated standalone.
Carlos Tommasi; Roberto Zennaro; Marco Ferrari; Lino Carnelli; Tamara Passera; Carla Lazzari; Paolo Silva; Marco Lamberti. Integration of Concentrated Solar Power CSP in the Oil & Gas Upstream Plants to Limit GHG Emissions and Fossil Fuel Dependence. Day 3 Wed, November 09, 2016 2016, 1 .
AMA StyleCarlos Tommasi, Roberto Zennaro, Marco Ferrari, Lino Carnelli, Tamara Passera, Carla Lazzari, Paolo Silva, Marco Lamberti. Integration of Concentrated Solar Power CSP in the Oil & Gas Upstream Plants to Limit GHG Emissions and Fossil Fuel Dependence. Day 3 Wed, November 09, 2016. 2016; ():1.
Chicago/Turabian StyleCarlos Tommasi; Roberto Zennaro; Marco Ferrari; Lino Carnelli; Tamara Passera; Carla Lazzari; Paolo Silva; Marco Lamberti. 2016. "Integration of Concentrated Solar Power CSP in the Oil & Gas Upstream Plants to Limit GHG Emissions and Fossil Fuel Dependence." Day 3 Wed, November 09, 2016 , no. : 1.
This article analyzed the potential energy recovery from rather small quantities of associated gas (<2000 m3/h), where the on-site electricity generation within the oil extraction field may represent a cost-effective solution as an alternative to flare combustion. Various power plant technologies were considered and compared from both the economic and avoided CO2 emissions points of view. It turned out that adopting a scheme with non-derated internal-combustion engines (ICE) fed by treated gas, and partial gas flaring, the most cost-effective result was obtained, showing a payback time of about 5 years and an internal rate of return (IRR) of 42.2%.
P. Iora; P. Bombarda; S. L. Gómez Aláez; C. Invernizzi; T. Rajabloo; Paolo Silva. Flare gas reduction through electricity production. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 2016, 38, 3116 -3124.
AMA StyleP. Iora, P. Bombarda, S. L. Gómez Aláez, C. Invernizzi, T. Rajabloo, Paolo Silva. Flare gas reduction through electricity production. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2016; 38 (21):3116-3124.
Chicago/Turabian StyleP. Iora; P. Bombarda; S. L. Gómez Aláez; C. Invernizzi; T. Rajabloo; Paolo Silva. 2016. "Flare gas reduction through electricity production." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 38, no. 21: 3116-3124.
The presented work compares two optimization models for combined heat and power (CHP) energy systems scheduling. Both models are focused on the evaluation of the best operating strategy to run a defined cogeneration system that is dealing with time-variable loads and tariffs. The simultaneous usage of different prime movers operating in parallel is taken into consideration as well as their part load performance, the influence of ambient temperature, and the usage of a heat storage system. One of the models is heuristic and adopts an optimization strategy based on a multi-step approach: it simulates several cases according to a pre-defined path exploring the most reasonable operational modes and comparing them systematically. The other one relies on a mathematical approach. A Mixed Integer Linear Programming (MILP) algorithm has been developed in order to deal with more complex systems without the need of predefining a too large variety of optimization paths according to the case. Results of the two models are compared against a test case based on real plant specifications, discussing their performance, by the point of view of simulation capabilities, quality of the optimization results, and calculation time.
Aldo Bischi; Estibaliz Perez-Iribarren; Stefano Campanari; Giampaolo Manzolini; Emanuele Martelli; Paolo Silva; Ennio Macchi; José María Pedro Sala-Lizarraga. Cogeneration systems optimization: Comparison of multi-step and mixed integer linear programming approaches. International Journal of Green Energy 2016, 13, 781 -792.
AMA StyleAldo Bischi, Estibaliz Perez-Iribarren, Stefano Campanari, Giampaolo Manzolini, Emanuele Martelli, Paolo Silva, Ennio Macchi, José María Pedro Sala-Lizarraga. Cogeneration systems optimization: Comparison of multi-step and mixed integer linear programming approaches. International Journal of Green Energy. 2016; 13 (8):781-792.
Chicago/Turabian StyleAldo Bischi; Estibaliz Perez-Iribarren; Stefano Campanari; Giampaolo Manzolini; Emanuele Martelli; Paolo Silva; Ennio Macchi; José María Pedro Sala-Lizarraga. 2016. "Cogeneration systems optimization: Comparison of multi-step and mixed integer linear programming approaches." International Journal of Green Energy 13, no. 8: 781-792.
Micro-cogeneration Stirling units are promising for residential applications because of high total efficiencies, favorable ratios of thermal to electrical powers and low CO as well as NOx emissions. This work focuses on the experimental and the numerical analysis of a commercial unit generating 8 kW of hot water (up to 15 kW with an auxiliary burner) and 1 kW of electricity burning natural gas. In the experimental campaign, the initial pressure of the working fluid is changed in a range from 9 to 24 barg – 20 barg being the nominal value – while the inlet temperature of the water loop and its mass flow rate are kept at the nominal conditions of, respectively, 50°C and 0.194 kg/s. The experimental results indicate clearly that the initial pressure of the working fluid – Nitrogen – affects strongly the net electrical power output and efficiency. The best performance for the output and efficiency of 943 W and 9.6% (based on the higher heating value of the burnt natural gas) are achieved at 22 barg. On the other hand, the thermal power trend indicates a maximum value of 8420 W at the working pressure of 24 barg, which corresponds to a thermal efficiency of 84.7% (again based on higher heating value). Measurements are coupled to a detailed model based on a modification of the work by Urieli and Berchowitz. Thanks to the tuning with the experimental results, the numerical model allows investigating the profiles of the main thermodynamic parameters and heat losses during the cycle, as well as estimating those physical properties that are not directly measurable. The major losses turn to be the wall parasitic heat conduction from heater to cooler and the non-unitary effectiveness of the regenerator
Gianluca Valenti; Paolo Silva; N. Fergnani; S. Campanari; A. Ravidà; Gioele Di Marcoberardino; E. Macchi. Experimental and numerical study of a micro-cogeneration Stirling unit under diverse conditions of the working fluid. Applied Energy 2015, 160, 920 -929.
AMA StyleGianluca Valenti, Paolo Silva, N. Fergnani, S. Campanari, A. Ravidà, Gioele Di Marcoberardino, E. Macchi. Experimental and numerical study of a micro-cogeneration Stirling unit under diverse conditions of the working fluid. Applied Energy. 2015; 160 ():920-929.
Chicago/Turabian StyleGianluca Valenti; Paolo Silva; N. Fergnani; S. Campanari; A. Ravidà; Gioele Di Marcoberardino; E. Macchi. 2015. "Experimental and numerical study of a micro-cogeneration Stirling unit under diverse conditions of the working fluid." Applied Energy 160, no. : 920-929.
In this paper the possible replacement of conventional metallic heat exchangers with plastic components is investigated with reference to low size Organic Rankine Cycles, aiming at a reduction of the plant investment cost.\ud \ud A thermodynamic optimization of a 20 kW regenerative ORC plant, representative of a low temperature (<140 degrees C) heat recovery application, has been carried out according to the presently available data for plastic shell and tubes heat exchangers offered on the market.\ud \ud N-heptane was selected as the working fluid, thanks to the capability to operate within the pressure limits for evaporation and condensation processes imposed by the adoption of plastic components. Finally, the potential economic benefit of the plastic solution in comparison with conventional heat exchangers made of carbon steel was evaluated for the whole plant; the case of enhanced materials adoption, which is mandatory for the evaporator in presence of corrosive heat source media, was also considered.\ud \ud It turns out that advantages of the proposed solution become appreciable whenever the presence of corrosive heat source media requires the use of materials other than carbon steel. For instance, for a plant availability of 5000 h/year and discount rate of 10%, we obtain a cost of the produced electricity of 94.8 $/MW h, 95.4 $/MW h, 101.5 $/MW h, and 118.9 $/MW h respectively for plastic, carbon steel, stainless steel and titanium solutions. (C) 2015 Elsevier Ltd. All rights reserved
S.L. Gómez Aláez; P. Bombarda; C.M. Invernizzi; Paolo Iora; Paolo Silva. Evaluation of ORC modules performance adopting commercial plastic heat exchangers. Applied Energy 2015, 154, 882 -890.
AMA StyleS.L. Gómez Aláez, P. Bombarda, C.M. Invernizzi, Paolo Iora, Paolo Silva. Evaluation of ORC modules performance adopting commercial plastic heat exchangers. Applied Energy. 2015; 154 ():882-890.
Chicago/Turabian StyleS.L. Gómez Aláez; P. Bombarda; C.M. Invernizzi; Paolo Iora; Paolo Silva. 2015. "Evaluation of ORC modules performance adopting commercial plastic heat exchangers." Applied Energy 154, no. : 882-890.
Stirling engines are a promising candidate for micro-cogeneration in residential and small-scale tertiary applications. Due to the variability of energy demand profiles and electricity tariffs, real applications often require to operate the cogeneration unit with multiple daily starts and stops, especially during summer and intermediate seasons. This work focuses on the experimental analysis of a commercial 1 kWel Stirling unit, burning natural gas and generating 8 kWth of useful heat through hot water and up to 12 kWth with an auxiliary burner, when subjected to cyclic on-off operation. The scope is collecting useful data about energy balances and emissions during on-off transients, which can be later used to optimize the management of the cogeneration unit when coupled with real users. Different cyclic tests are experimented (with intermediate stops and operation of either one or two burners), keeping the temperature of the cogeneration water at the unit inlet at 50°C and its mass flow rate at the nominal value of 0.194 kg/s. The Stirling unit has shown an electrical efficiency of 8.9%, based on Lower Heating Value (LHV), in the most favorable cyclic test and 8.2% in the worst case, while thermal efficiency ranges between 91.0 and 92.6%. For comparison, the steady state electrical efficiency is 10.8% (LHV) while the thermal is 90.1% with only one burner running in full cogeneration mode. Steady state efficiencies become 7.2% and 92.0% (LHV), respectively, with the auxiliary burner running. The significant reduction of average electrical efficiency suggests the necessity to limit the frequency of starts and stops in real operation. Emissions show modest peaks in NOx and CO, which do not compromise the environmental impact, confirming the low emission combustion features of the Stirling unit
Gianluca G.Valenti; S. Campanari; Paolo Silva; A. Ravidà; E. Macchi; Aldo Bischi. On-off Cyclic Testing of a Micro-cogeneration Stirling Unit. Energy Procedia 2015, 75, 1197 -1201.
AMA StyleGianluca G.Valenti, S. Campanari, Paolo Silva, A. Ravidà, E. Macchi, Aldo Bischi. On-off Cyclic Testing of a Micro-cogeneration Stirling Unit. Energy Procedia. 2015; 75 ():1197-1201.
Chicago/Turabian StyleGianluca G.Valenti; S. Campanari; Paolo Silva; A. Ravidà; E. Macchi; Aldo Bischi. 2015. "On-off Cyclic Testing of a Micro-cogeneration Stirling Unit." Energy Procedia 75, no. : 1197-1201.