The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform
Pier Ruggero Spina - One of the best experts on this subject based on the ideXlab platform.
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Estimation of the Particle Deposition on a Transonic Axial Compressor Blade
Journal of Engineering for Gas Turbines and Power, 2015Co-Authors: Alessio Suman, Nicola Aldi, Mirko Morini, Michele Pinelli, Rainer Kurz, Klaus Brun, Pier Ruggero SpinaAbstract:Solid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Usually, foulants in the ppm range, not captured by the air filtration system, i.e., (0–2) μm cause deposits on blading and result in a severe performance drop of the Compressor. It is of great interest to the industry to determine which areas of the Compressor airfoils are interested by these contaminants as a function of the location of the power unit. The aim of this work is the estimation of the actual deposits on the blade surface in terms of location and quantity. The size of the particles, their concentrations, and the filtration efficiency are specified in order to perform a realistic quantitative analysis of the fouling phenomena in an axial Compressor. This study combines, for the first time, the impact/adhesion characteristic of the particles obtained through a computational fluid dynamics (CFD) and the real size distribution of the contaminants in the air swallowed by the Compressor. The blade zones affected by the deposits are clearly reported by using easy-to-use contaminant maps realized on the blade surface in terms of contaminant mass. The analysis showed that particular fluid-dynamic phenomena such as separation, shock waves, and tip leakage vortex strongly influence the pattern deposition. The combination of the smaller particles (0.15 μm) and the larger ones (1.50 μm) determines the highest amounts of deposits on the leading edge (LE) of the Compressor airfoil. From these analyses, some guidelines for proper installation and management of the power plant (in terms of filtration systems and washing strategies) can be drawn.
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Estimation of the Particle Deposition on a Transonic Axial Compressor Blade
Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy, 2015Co-Authors: Alessio Suman, Nicola Aldi, Mirko Morini, Michele Pinelli, Rainer Kurz, Klaus Brun, Pier Ruggero SpinaAbstract:Solid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Usually, foulants in the ppm range, not captured by the air filtration system (0–2) μm cause deposits on blading and result in a severe performance drop of the Compressor. It is of great interest to the industry to determine which areas of the Compressor airfoils are interested by these contaminants as a function of the location of the power unit. The aim of this work is the estimation of the actual deposits on the blade surface in terms of location and quantity. The size of the particles, their concentrations and the filtration efficiency are specified in order to perform a realistic quantitative analysis of the fouling phenomena in an axial Compressor. This study combines, for the first time, the impact/adhesion characteristic of the particles obtained through a CFD and the real size distribution of the contaminants in the air swallowed by the Compressor. The blade zones affected by deposits are clearly reported by using easy-to-use contaminant maps realized on the blade surface in terms of contaminant mass. The analysis showed that particular fluid-dynamic phenomena such as separation, shock waves and tip leakage vortex strongly influence the pattern deposition. The combination of the smaller particles (0.15 μm) and the larger ones (1.50 μm) determines the highest amounts of deposits on the leading edge of the Compressor airfoil. From these analyses, some guidelines for proper installation and management of the power plant (in terms of filtration systems and washing strategies) can be drawn.
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An Interdisciplinary Approach to Study the Fouling Phenomenon
Energy Procedia, 2015Co-Authors: Nicola Aldi, Mirko Morini, Michele Pinelli, Pier Ruggero Spina, Alessio SumanAbstract:AbstractSolid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Foulants in the ppm range which are not captured by the air filtration system usually cause deposits on blading,which results in a severe drop in the performance of the Compressor.Through the interdisciplinary approach proposed in this paper, it is possible to determine the evolution of the fouling phenomenon through the integration of several studies in different research fields: (i) numerical simulation, (ii) power plant characteristicsand (iii) particle-adhesion characteristics.This paper shows the possibility of linking the numerical results related to the impact/adhesion characteristic of the particles with the actual air contamination data and operating condition of the power units. In fact, the size of the particles, their concentrations and the filtration efficiency represent the major contributors to performing a realistic quantitative analysis of the fouling phenomena in an axial Compressor.The integration of these research fields could represent a valuable support for the investigation of the relationship between Compressor airfoil design and fouling rate
Alessio Suman - One of the best experts on this subject based on the ideXlab platform.
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Estimation of the Particle Deposition on a Transonic Axial Compressor Blade
Journal of Engineering for Gas Turbines and Power, 2015Co-Authors: Alessio Suman, Nicola Aldi, Mirko Morini, Michele Pinelli, Rainer Kurz, Klaus Brun, Pier Ruggero SpinaAbstract:Solid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Usually, foulants in the ppm range, not captured by the air filtration system, i.e., (0–2) μm cause deposits on blading and result in a severe performance drop of the Compressor. It is of great interest to the industry to determine which areas of the Compressor airfoils are interested by these contaminants as a function of the location of the power unit. The aim of this work is the estimation of the actual deposits on the blade surface in terms of location and quantity. The size of the particles, their concentrations, and the filtration efficiency are specified in order to perform a realistic quantitative analysis of the fouling phenomena in an axial Compressor. This study combines, for the first time, the impact/adhesion characteristic of the particles obtained through a computational fluid dynamics (CFD) and the real size distribution of the contaminants in the air swallowed by the Compressor. The blade zones affected by the deposits are clearly reported by using easy-to-use contaminant maps realized on the blade surface in terms of contaminant mass. The analysis showed that particular fluid-dynamic phenomena such as separation, shock waves, and tip leakage vortex strongly influence the pattern deposition. The combination of the smaller particles (0.15 μm) and the larger ones (1.50 μm) determines the highest amounts of deposits on the leading edge (LE) of the Compressor airfoil. From these analyses, some guidelines for proper installation and management of the power plant (in terms of filtration systems and washing strategies) can be drawn.
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Estimation of the Particle Deposition on a Transonic Axial Compressor Blade
Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy, 2015Co-Authors: Alessio Suman, Nicola Aldi, Mirko Morini, Michele Pinelli, Rainer Kurz, Klaus Brun, Pier Ruggero SpinaAbstract:Solid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Usually, foulants in the ppm range, not captured by the air filtration system (0–2) μm cause deposits on blading and result in a severe performance drop of the Compressor. It is of great interest to the industry to determine which areas of the Compressor airfoils are interested by these contaminants as a function of the location of the power unit. The aim of this work is the estimation of the actual deposits on the blade surface in terms of location and quantity. The size of the particles, their concentrations and the filtration efficiency are specified in order to perform a realistic quantitative analysis of the fouling phenomena in an axial Compressor. This study combines, for the first time, the impact/adhesion characteristic of the particles obtained through a CFD and the real size distribution of the contaminants in the air swallowed by the Compressor. The blade zones affected by deposits are clearly reported by using easy-to-use contaminant maps realized on the blade surface in terms of contaminant mass. The analysis showed that particular fluid-dynamic phenomena such as separation, shock waves and tip leakage vortex strongly influence the pattern deposition. The combination of the smaller particles (0.15 μm) and the larger ones (1.50 μm) determines the highest amounts of deposits on the leading edge of the Compressor airfoil. From these analyses, some guidelines for proper installation and management of the power plant (in terms of filtration systems and washing strategies) can be drawn.
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An Interdisciplinary Approach to Study the Fouling Phenomenon
Energy Procedia, 2015Co-Authors: Nicola Aldi, Mirko Morini, Michele Pinelli, Pier Ruggero Spina, Alessio SumanAbstract:AbstractSolid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Foulants in the ppm range which are not captured by the air filtration system usually cause deposits on blading,which results in a severe drop in the performance of the Compressor.Through the interdisciplinary approach proposed in this paper, it is possible to determine the evolution of the fouling phenomenon through the integration of several studies in different research fields: (i) numerical simulation, (ii) power plant characteristicsand (iii) particle-adhesion characteristics.This paper shows the possibility of linking the numerical results related to the impact/adhesion characteristic of the particles with the actual air contamination data and operating condition of the power units. In fact, the size of the particles, their concentrations and the filtration efficiency represent the major contributors to performing a realistic quantitative analysis of the fouling phenomena in an axial Compressor.The integration of these research fields could represent a valuable support for the investigation of the relationship between Compressor airfoil design and fouling rate
Lars E. Bakken - One of the best experts on this subject based on the ideXlab platform.
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Gas Turbine Fouling Offshore: Correction Methodology Compressor Efficiency
Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy, 2017Co-Authors: Stian Madsen, Lars E. BakkenAbstract:Gas turbine performance has been analyzed for a fleet of GE LM2500 engines at two Statoil offshore fields in the North Sea. Both generator drive engines and Compressor driver engines have been analyzed, covering both the LM2500 base and plus configurations, as well as the SAC and DLE combustor configurations. Several of the Compressor drive engines are running at peak load (T5.4 control), and the production rate is thus limited to the available power from these engines. The majority of the engines discussed run continuously without redundancy, implying that gas turbine uptime is critical for the field’s production and economy. Previous studies and operational experience have emphasized that the two key factors to minimize Compressor fouling are the optimum designs of the inlet air filtration system and the water wash system. An optimized inlet air filtration system, in combination with daily online water wash (at high water-to-air ratio), are the key factors to achieve successful operation at longer intervals between offline washes and higher average engine performance. Operational experience has documented that the main gas turbine recoverable deterioration is linked to the Compressor Section. The main performance parameter when monitoring Compressor fouling is the gas turbine Compressor efficiency. Previous studies have indicated that inlet depression (air mass flow at Compressor inlet) is a better parameter when monitoring Compressor fouling, whereas instrumentation for inlet depression is very seldom implemented on offshore gas turbine applications. The main challenge when analyzing Compressor efficiency (uncorrected) is the large variation in efficiency during the periods between offline washes, mainly due to operation at various engine loads and ambient conditions. Understanding the gas turbine performance deterioration is of vital importance. Trending of the deviation from the engine baseline facilitates load-independent monitoring of the gas turbine’s condition. Instrument resolution and repeatability are key factors for attaining reliable results in the performance analysis. A correction methodology for Compressor efficiency has been developed, which improves the long term trend data for effective diagnostics of Compressor degradation. Avenues for further research and development are proposed in order to further increase the understanding of the deterioration mechanisms, as well as gas turbine performance and response.
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Performance Deterioration of Intake Air Filters for Gas Turbines in Offshore Installations
Volume 5: Industrial and Cogeneration; Microturbines and Small Turbomachinery; Oil and Gas Applications; Wind Turbine Technology, 2010Co-Authors: Olaf Brekke, Lars E. BakkenAbstract:Efficient inlet air filtration is a key element for limiting fouling, erosion, and corrosion in the Compressor Section of offshore gas turbine installations. Current filtration systems are normally successful in preventing serious erosion and corrosion problems in the Compressor Section, but significant performance deterioration caused by Compressor fouling still remains a challenge. This performance deterioration increases fuel consumption and emissions and has a particularly severe economic impact when it reduces oil and gas production. Operating experience from different offshore installations has shown that the deterioration rate in gas turbine performance increases when the turbines are operating in wet or humid weather and that the differential pressure loss over the intake system is affected by ambient humidity. An experimental test rig has been built in the laboratory at the Norwegian University of Science and Technology (NTNU) in order to increase understanding of the fundamentals related to gas turbine inlet air filtration. This paper presents the results from an experimental investigation of the performance of gas turbine inlet air filter elements that have been in operation offshore. Performance under both dry and wet conditions is assessed. Different types of filter elements show significantly different changes in differential pressure signature when exposed to moisture, and all of the tested filter elements demonstrate a loss of accumulated contamination after operating in wet conditions. Hence, contaminants originally accumulated by the filter elements are re-entrained into the airstream on the downstream side of the filters when they are exposed to moisture. The change in differential pressure signature as a result of operating in wet conditions demonstrates another weakness of solely applying differential pressure for condition monitoring of the filter system.
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Compressor Fouling in Gas Turbines Offshore: Composition and Sources From Site Data
Volume 5: Microturbines and Small Turbomachinery; Oil and Gas Applications, 2009Co-Authors: Olaf Brekke, Lars E. Bakken, Elisabet SyverudAbstract:Contamination in the intake air causes fouling in the Compressor Section of gas turbines. The amount and type of fouling present in the Compressor Section is site-specific, and knowledge of its composition is important in order to achieve efficient intake air filtration. This knowledge is also of great importance when optimizing both online and offline Compressor wash regimes. This paper presents the results of an investigation of Compressor fouling in two different offshore gas turbine installations. Fouling samples collected from various locations in the gas turbine air intakes, inlet guide vanes, and first Compressor rotor stages were analyzed in a laboratory using an electron probe micron analyzer. The structure and composition of the analyzed Compressor fouling is determined, and the probable sources of the different elements are identified.© 2009 ASME
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Filtration of Gas Turbine Intake Air in Offshore Installations: The Gap Between Test Standards and Actual Operating Conditions
Volume 5: Microturbines and Small Turbomachinery; Oil and Gas Applications, 2009Co-Authors: Olaf Brekke, Lars E. Bakken, Elisabet SyverudAbstract:Gas turbine performance deterioration caused by fouling in the Compressor Section is a well known phenomenon in offshore installations. This performance deterioration not only increases fuel consumption and emissions but also has a severe economic impact when it reduces oil and gas production. Because fouling in the Compressor Section is commonly caused by intake air contamination, gas turbines offshore have air inlet filtration systems in order to limit the amount of ingested contaminants. Many different filtration systems from various suppliers are in operation offshore. Manufacturers supply documentation for their filtration system based on several international standards, and it can be challenging for the operator to make a direct comparison of different filtration systems. The comparison is further complicated by the fact that the characteristic offshore challenges related to salt and moisture in the intake air are not adequately covered in international standards, and these challenges are handled and documented differently among the manufacturers. This paper analyzes the challenges related to choosing the best filter solution for an offshore gas turbine installation based on data from offshore sites in the North Sea. The relevance of test requirements in applicable international standards and available supplier documentation is evaluated based on actual operating conditions offshore. Deviations among international test standard requirements, available manufacturer documentation, and actual operating conditions offshore are identified, and improved test requirements are suggested. In addition, this paper addresses the long-term effects of filter contamination and methods for intake filter monitoring based on data from offshore sites in the North Sea.
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Online Water Wash Tests of GE J85-13
Journal of Turbomachinery, 2007Co-Authors: Elisabet Syverud, Lars E. BakkenAbstract:Gas turbine performance deterioration can negatively affect overall production capacity of power plants and cause major economic losses. Gas turbines deteriorate from fouling in the Compressor Section, and online washing is often applied to recover their performance. The success of online washing depends on site-specific issues, and current systems are inconsistent in use and their effectiveness is difficult to test. The objective of this work is to determine the fundamental mechanisms of axial Compressor performance deterioration and recovery through online washing.Empirical data from online washing of RB211-24G at an offshore site were analyzed in the initial phase of research. Empirical data from accelerated salt deterioration and online water washing of a GE J85-13 jet engine were unique to this project. First overall Compressor deterioration and single stage performance deterioration were measured using inter-stage gas path instrumentation. Secondly, salt deposits were analyzed to characterize the stage surface roughness and fouling distribution. Finally, recovery through online washing was evaluated. Quasi-one-dimensional models were developed for the GE J85-13 to aid in the test data analysis and to verify the applicability of deterioration loss models to fouled Compressors.The study shows that detection of Compressor deterioration can be hampered by nonlinear sensitivities to fouling. Engine control modes must be accounted for to avoid misreading the deterioration rate and production capacity. Flow rate was found as the most sensitive deterioration parameter in the GE J85-13. Fouling affected all parts of the stage characteristics reducing flow, pressure and head. The models successfully reflected the deterioration mechanisms although the effects of deterioration were under-predicted. This study shows the importance of applying Reynolds corrections to deteriorated Compressors.Online washing efficiency is predominantly affected by the water flow rate. Small droplets and low flow rates increase the fouling in the aft stages, and increased injection time cannot compensate for low flow rates. For effective water washing of the entire Compressor Section the recommended water-to-air ratio is between 0.8 to 2%.The major contributions of this work are presented in four papers contained in the Appendices.
Nicola Aldi - One of the best experts on this subject based on the ideXlab platform.
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Estimation of the Particle Deposition on a Transonic Axial Compressor Blade
Journal of Engineering for Gas Turbines and Power, 2015Co-Authors: Alessio Suman, Nicola Aldi, Mirko Morini, Michele Pinelli, Rainer Kurz, Klaus Brun, Pier Ruggero SpinaAbstract:Solid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Usually, foulants in the ppm range, not captured by the air filtration system, i.e., (0–2) μm cause deposits on blading and result in a severe performance drop of the Compressor. It is of great interest to the industry to determine which areas of the Compressor airfoils are interested by these contaminants as a function of the location of the power unit. The aim of this work is the estimation of the actual deposits on the blade surface in terms of location and quantity. The size of the particles, their concentrations, and the filtration efficiency are specified in order to perform a realistic quantitative analysis of the fouling phenomena in an axial Compressor. This study combines, for the first time, the impact/adhesion characteristic of the particles obtained through a computational fluid dynamics (CFD) and the real size distribution of the contaminants in the air swallowed by the Compressor. The blade zones affected by the deposits are clearly reported by using easy-to-use contaminant maps realized on the blade surface in terms of contaminant mass. The analysis showed that particular fluid-dynamic phenomena such as separation, shock waves, and tip leakage vortex strongly influence the pattern deposition. The combination of the smaller particles (0.15 μm) and the larger ones (1.50 μm) determines the highest amounts of deposits on the leading edge (LE) of the Compressor airfoil. From these analyses, some guidelines for proper installation and management of the power plant (in terms of filtration systems and washing strategies) can be drawn.
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Estimation of the Particle Deposition on a Transonic Axial Compressor Blade
Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy, 2015Co-Authors: Alessio Suman, Nicola Aldi, Mirko Morini, Michele Pinelli, Rainer Kurz, Klaus Brun, Pier Ruggero SpinaAbstract:Solid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Usually, foulants in the ppm range, not captured by the air filtration system (0–2) μm cause deposits on blading and result in a severe performance drop of the Compressor. It is of great interest to the industry to determine which areas of the Compressor airfoils are interested by these contaminants as a function of the location of the power unit. The aim of this work is the estimation of the actual deposits on the blade surface in terms of location and quantity. The size of the particles, their concentrations and the filtration efficiency are specified in order to perform a realistic quantitative analysis of the fouling phenomena in an axial Compressor. This study combines, for the first time, the impact/adhesion characteristic of the particles obtained through a CFD and the real size distribution of the contaminants in the air swallowed by the Compressor. The blade zones affected by deposits are clearly reported by using easy-to-use contaminant maps realized on the blade surface in terms of contaminant mass. The analysis showed that particular fluid-dynamic phenomena such as separation, shock waves and tip leakage vortex strongly influence the pattern deposition. The combination of the smaller particles (0.15 μm) and the larger ones (1.50 μm) determines the highest amounts of deposits on the leading edge of the Compressor airfoil. From these analyses, some guidelines for proper installation and management of the power plant (in terms of filtration systems and washing strategies) can be drawn.
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An Interdisciplinary Approach to Study the Fouling Phenomenon
Energy Procedia, 2015Co-Authors: Nicola Aldi, Mirko Morini, Michele Pinelli, Pier Ruggero Spina, Alessio SumanAbstract:AbstractSolid particle ingestion is one of the principal degradation mechanisms in the Compressor Section of heavy-duty gas turbines. Foulants in the ppm range which are not captured by the air filtration system usually cause deposits on blading,which results in a severe drop in the performance of the Compressor.Through the interdisciplinary approach proposed in this paper, it is possible to determine the evolution of the fouling phenomenon through the integration of several studies in different research fields: (i) numerical simulation, (ii) power plant characteristicsand (iii) particle-adhesion characteristics.This paper shows the possibility of linking the numerical results related to the impact/adhesion characteristic of the particles with the actual air contamination data and operating condition of the power units. In fact, the size of the particles, their concentrations and the filtration efficiency represent the major contributors to performing a realistic quantitative analysis of the fouling phenomena in an axial Compressor.The integration of these research fields could represent a valuable support for the investigation of the relationship between Compressor airfoil design and fouling rate
Stefano Campanari - One of the best experts on this subject based on the ideXlab platform.
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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, 2020Co-Authors: Marco Astolfi, Adriano Hirn, Giulio Guandalini, Marco Belloli, Paolo Silva, Stefano CampanariAbstract:Abstract 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.
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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 Sys, 2019Co-Authors: Marco Astolfi, Adriano Hirn, Giulio Guandalini, Marco Belloli, Paolo Silva, Stefano CampanariAbstract:Abstract 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.