Gas Turbine Power Plant Research Articles

Influence of Surrounding Air Temperature and Humidity upon the Performance of a Gas Turbine Power Plant

Nowadays, energy demand continuously rises while energy stocks are dwindling. Using current resources more effectively is crucial for the world. A wide method to effectively utilize energy is to generate electricity using thermal gas turbines (GT). One of the most important problems that gas turbines suffer from is high ambient air temperature especially in summer. The current paper details the effects of ambient conditions on the performance of a gas turbine through energy audits taking into account the influence of ambient conditions on the specific heat capacity ( , isentropic exponent ( ) as well as the gas constant of air . A computer program was developed to examine the operation of a power plant at various ambient temperatures and relative humidities. The ambient temperatures ranged from 0 to 45 ºC, with relative humidities from 10 to 90%. The obtained results show that a GT operated at increased inlet air temperatures is characterized by lower net power and thermal efficiency. At higher inlet air temperatures, increased relative humidity has a slight positive impact on the GT cycle net power and its thermal efficiency. Net output power of the GT decreased from 93.3 MW at 15 °C to 70 MW at 45 °C. Its efficiency decreased from 32.32% at 5 °C to 28.3% at 30 °C. Although fuel consumption is reduced, the heat rate as well and the specific fuel consumption (SFC) are enhanced. SFC increased by 5.36% with a 10 °C temperature rise in temperature at a constant relative humidity. Therefore, use of a gas turbine with inlet air cooling and humidification is appropriate for improved GT efficiency.

Techno-economic analysis on the balance of plant (BOP) equipment due to switching fuel from natural gas to hydrogen in gas turbine power plants

<abstract> <p>The concerns over greenhouse gas emissions, environmental impacts, climate change, and sustainability continue to grow. As a result of countermeasures, many modern gas turbine power plants and combined cycle power plants are considering to use hydrogen as a clean fuel alternative to fossil fuels in the power plant industry. We assessed the implications of such transition from natural gas to hydrogen as fuel in a gas turbine power plant's balance of plant (BOP) equipment. Using the DWSIM process simulation software and the methodology of compression power changes against different gas compositions, the impact of blending hydrogen with natural gas on temperature differentials, energy consumption, adiabatic efficiency, compression power, and economic implications in gas turbine power plants were examined in this paper. We discovered, through analysis, that there was not a noticeable boost in compression power or energy consumption when 50% hydrogen and 50% natural gas were blended. Similarly, there was no discernible difference in temperature differentials or adiabatic efficiency when 30% hydrogen and 70% natural gas were blended. Moreover, mixing 50% hydrogen and 50% natural gas did not result in a noticeable cost climb. In addition, the techno-economic analysis presented in this paper offered valuable insights for power plant engineers, power generation companies, investors in energy sectors, and policymakers, highlighting the nature of the fuel shift and its implications on the economy and technology.</p> </abstract>

Assessing factors influencing green hydrogen conversion at Vietnam's gas turbine power plants using combined SWOT-AHP analysis method

Assessing factors influencing green hydrogen conversion at Vietnam's gas turbine power plants using combined SWOT-AHP analysis method

ПОРІВНЯЛЬНИЙ АНАЛІЗ ДИНАМІЧНИХ ВЛАСТИВОСТЕЙ ГАЗОТУРБІННИХ УСТАНОВОК ШИРОКОГО ДІАПАЗОНУ ПОТУЖНОСТЕЙ ПРИ РОБОТІ НА ЧАСТКОВИХ ЕЛЕКТРИЧНИХ НАВАНТАЖЕННЯХ

Abstract. The article considers the possibility of using gas turbine power plants when operating at partial electrical loads. This option of using gas turbine plants can help reduce the unevenness between electricity production and consumption, which is associated with the difficult operating conditions of the Ukrainian power system. The main disadvantages of nuclear power plants (the main source of electricity generation in Ukraine), which do not allow them to compensate for the unevenness of the power system in transient and dynamic modes, are considered. The paper analyses the dynamic properties and characteristics of gas turbine units (GTUs) of a wide range of capacities: small, medium and large installed capacities. As a result of the modeling, it was found that the inertial properties of a gas turbine unit increase with the increase in the rated power of the unit. The paper presents the results of modeling the dynamic characteristics of gas turbine plants of small, medium and large capacity when the electrical load changes. The paper presents the transient processes of controlling the rotor speed of a gas turbine engine with optimal controller settings and settings calculated for partial loads of a gas turbine installation. The change in the quality of the transient processes of controlling the rotor speed of a gas turbine unit when operating at partial electrical loads (100%, 75%, and 50%) compared to the installed capacity is analyzed. Keywords: gas turbine installation, partial electrical load, dynamic characteristics, transient control processes, control quality indicators.

METHODS OF IMPROVING THE EFFICIENCY OF ENERGY SUPPLY TO OIL AND GAS ENTERPRISES

Realization of high-tech designs in gas and oil industry contributes to more efficient functioning of production. Development of quality minerals is not a scientific and technical progress, but a stable level indicator based on the general economic aspect.Therefore, the introduction of high quality updated technologies and additions to production functioning systems always leads to a greater need for their use. To maximize energy efficiency in gas and oil production, it is recommended to use high-quality autonomous power sources. The sets of optimization possibilities on algorithms of systems of distribution of power loads of electric transformer substations taking into account large productivity of producing wells at oil fields are developed. Recommendations on quality utilization, developed on the basis of long algorithms, allow to increase step-by-step nominal level of power loads at pumping units operation. It is proved that to maximize energy efficiency enterprises need to use their own high-quality autonomous power sources. The article considers the efficiency and cost-effective possibilities of production energy-consuming and quality functioning equipment in the oil&gas industry. In addition, taking into account the benefits on the basis of the study was carried out a large-scale analysis of data on the characteristics of relative efficiency and reliability to the technical condition of gas turbine and gas piston power plants.

Technical and Economical Evaluation of the enhancement of gas turbine power plant using air cooling fogging system

Technical and Economical Evaluation of the enhancement of gas turbine power plant using air cooling fogging system

Concentration of carbon dioxide in products of combustion of GTE NK-16ST and NK-16-18ST

This paper considers the design of two combustion chambers of a gas turbine engine running on natural gas. One combustion chamber has 32 burners, and the other has 136 nozzles located in two rows in the flame tube head. A major contributor to global warming is considered to be the significant emissions of greenhouse gases, primarily CO2, including those emitted by gas turbine engines and power plants. The reduction of carbon dioxide levels by developing a set of structural measures in the combustion chamber is one of the urgent tasks of engine construction which requires a solution in order to meet modern environmental requirements for gas turbine engines serving as blower drives for gas compressor units. The presented research is dedicated to the analysis of influence of changes in combustion chamber design on reduction of СО2 level in exhaust gases of gas turbine engine NK-16ST. Two modifications of the combustion chamber are considered. The first one was a serial combustion chamber with diffusion combustion, the second one was a modernized combustion chamber with a modified front device. Each of the chambers considered was tested as part of the engine. During the study, combustion products were sampled directly in the exhaust shaft and their concentrations, including the CO2 content, were determined. As a result of this work, it was confirmed that there is a possibility to reduce the concentration of CO2 in the engine combustion products up to 20 % without affecting the engine parameters. This reduction in carbon dioxide content was made possible by reducing the completeness of fuel combustion in the combustion chamber. The obtained data on changes in CO2 concentration can be useful in selecting the most suitable mode of engine operation, and the presented approaches to combustion processes organization can be used by developers in designing combustion chambers of natural gas-fired gas turbine engines.

Yearly hour-by-hour performance evaluation of a SIEMENSE gas turbine power plant for Australia’s climate condition with and without a novel intake air pre-cooling strategy

The power production, fuel consumption and revenue of any gas turbine (GT) power plant are greatly affected by variations in ambient conditions (entering air into the compressor). This paper simulates and reports the power output and efficiency of a gas turbine-based power plant (SGT-750 SIEMENSE) using around 8000 h-by-hour yearly weather data of two regions of Australia (north and south) without pre-cooling, with sole M−cycle pre-cooling and finally with an innovative hybrid pre-cooler. The hybrid pre-cooler consists of a Maisotsenko indirect evaporative cooler (M−cycle) and an absorption chiller (ABC). Briefly, the results indicate that power raise of the GT plant using the M−cycle IEC alone is about 2 % in temperate regions and 4 % in hot regions, while it would be about 4 % and 6 % respectively if the hybrid pre-cooler is used. Reducing the inlet air temperature by 8–10 °C increases the generated power of a GT with pre-cooler by 8–9 %.

Analyzing Gas Turbine Performance Through Simulation and Performance Tests: Case Study of Gas Turbine Units in Jambi, Indonesia

The purpose of this research is to analyse and compare the performance of units 1 and 2 of the gas turbine (GT) power plant based on simulation results and tests in terms of performance, to identify factors causing a decrease in gas turbine performance, and provide recommendations to improve gas turbine. The study was carried out in GT units in Jambi, Indonesia. In this location, there are two identical GT units with a capacity of 34.25 megawatts electric (MWe). The analysis was carried out using three methods, namely performance test, inspection of the measurement instruments, and simulation of the thermodynamic performance using GT-Pro software. To improve the performance of the gas turbine, it is necessary to clean the compressor blades, online compressor washing or manual deposit cleaning on the compressor blades during the overhaul, calibrate manometers, and inspect the piping line of the differential pressure of Air Inlet Filter, and also carry out inspection and calibration of the exhaust gas thermocouple on numbers 1, 2, 5, and 8 of GT Unit 2. This research not only presents practical recommendations for improving the performance of GT in Jambi, Indonesia, but also contributes to the broader field of gas turbine technology. The findings and recommendations can be applied in the power generation industry worldwide, helping to enhance the efficiency and reliability gas turbine power plants.

The Characteristics of Hybrid Solar Micro Gas-Turbine Power Plants Operating at Partial Loads

The Characteristics of Hybrid Solar Micro Gas-Turbine Power Plants Operating at Partial Loads

Performance Optimization and Exergy Analysis of Thermoelectric Heat Recovery System for Gas Turbine Power Plants.

Thermoelectric (TE) waste heat recovery has attracted significant attention over the past decades, owing to its direct heat-to-electricity conversion capability and reliable operation. However, methods for application-specific, system-level TE design have not been thoroughly investigated. This work provides detailed design optimization strategies and exergy analysis for TE waste heat recovery systems. To this end, we propose the use of TE system equipped on the exhaust of a gas turbine power plant for exhaust waste heat recovery and use it as a case study. A numerical tool has been developed to solve the coupled charge and heat current equations with temperature-dependent material properties and convective heat transfer at the interfaces with the exhaust gases at the hot side and with the ambient air at the heat sink side. Our calculations show that at the optimum design with 50% fill factor and 6 mm leg thickness made of state-of-the-art Bi2Te3 alloys, the proposed system can reach power output of 10.5 kW for the TE system attached on a 2 m-long, 0.5 × 0.5 m2-area exhaust duct with system efficiency of 5% and material cost per power of 0.23 $/W. Our extensive exergy analysis reveals that only 1% of the exergy content of the exhaust gas is exploited in this heat recovery process and the exergy efficiency of the TE system can reach 8% with improvement potential of 85%.

Disturbance size estimation in Great Britain power system including combined cycle gas turbine power stations

With the substantial popularity of combined cycle gas turbine (CCGT) power plants in the nowadays power systems, special care must be taken to regulate frequency due to unique frequency response characteristic of the full-loaded CCGT units. This unique feature is documented in the literature; however, its effect on determining frequency response of the power systems was not addressed in detail. This study proposes a new analytical method to achieve a more accurate estimated size of a loss-of-generation disturbance. This method considers demand-side power deviations and transmission lines power loss as well as unique frequency response of the CCGT units following the event. Firstly, it is exposed that there is an approximately linear relationship between power and frequency deviations of these plants in a real-world power system despite the complexity of the CCGT model. This relationship may be represented by a negative droop gain. Next, the derived CCGT’s linear characteristic is formulated in the disturbance size estimation process. Finally, the effectiveness of the proposed modifications is demonstrated through extensive simulations on a 36-zone Great Britain equivalent test system.

Power and efficiency optimizations for an open cycle two-shaft gas turbine power plant

In finite-time thermodynamic analyses for various gas turbine cycles, there are two common models: one is closed-cycle model with thermal conductance optimization of heat exchangers, and another is open-cycle model with optimization of pressure drop (PD) distributions. Both of optimization also with searching optimal compressor pressure ratio (PR). This paper focuses on an open-cycle model. A two-shaft open-cycle gas turbine power plant (OCGTPP) is modeled in this paper. Expressions of power output (PP) and thermal conversion efficiency (TCE) are deduced, and these performances are optimized by varying the relative PD and compressor PR. The results show that there exist the optimal values (0.32 and 14.0) of PD and PR which lead to double maximum dimensionless PP (1.75). There also exists an optimal value (0.38) of area allocation ratio which leads to maximum TCE (0.37). Moreover, the performances of three types of gas turbine cycles, such as one-shaft and two-shaft ones, are compared. When the relative pressure drop at the compressor inlet is small, the TCE of third cycle is the biggest one; when this pressure drop is large, the PP of second cycle is the biggest one. The results herein can be applied to guide the preliminary designs of OCGTPPs.

Proposal, process development, and multi-aspect investigation of a novel environmentally friendly multigeneration process in arrangement with a sea water desalination unit

The present study focuses on the energy, exergy, economic, and environmental evaluations of a new multigeneration process integrated with a gas turbine power plant for an eco-friendly cascade heat recovery. This system includes an organic Rankine cycle, a sea water desalination unit, a combined cooling and power unit, and a dual organic Rankine cycle. The process is simulated by employing the Aspen HYSYS software. A parameter evaluation is performed to investigate the effect of operational conditions on the output of the new structure and its energy and exergy efficiencies. It is determined that the system is capable of producing cooling, heating, power, and fresh water products with capacities of 1096 kW, 51,040 kW, 148,500 kW, and 131.2 kg/s, respectively, in the baseline state. Additionally, it is found that the primary energy saving, thermal efficiency, electricity efficiency, energy utilization factor, energy efficiency, and exergy efficiency for the new structure are 31.9%, 13.4%, 39.0%, 52.4%, 52.7%, and 63.6%, respectively. The investigations demonstrate that the total exergy destruction is 146,675 kW, and the highest amount occurs in the desalination subsystem (46.4%). The evaluations describe that the new structure can reduce carbon dioxide emissions by 39.8% compared to conventional power and heat generation. The economic estimation indicates the proposed process has positive economic growth with a net present value of 502.99 M$. The values of the total unit cost of products, the cost of energy, and the internal rate of return equal 10.9 $/GJ, 0.057 $/kWh, and 5.08 year, respectively.

Blend of flue gas from a methane-fueled gas turbine power plant and syngas from biomass gasification process to feed a novel trigeneration application: Thermodynamic-economic study and optimization

Enhancing the stability and cost-effectiveness of gas turbine power plants while mitigating input costs, co-feed arrangements, and multi-heat recovery processes shows great promise. The present study introduces an innovative trigeneration application to energetically and economically modify the existing gas turbine cycle. This trigeneration system incorporates several components, namely a helium gas turbine power plant, a regenerative steam Rankine cycle, a domestic water heating unit, and a multi-effect desalination subsystem. The thermodynamic and economic factors were considered to assess the performance indexes. Furthermore, a thorough technical analysis was conducted on the thermodynamic and economic variables, considering the influence of five crucial decision-making factors. Also, the operation mode of the system was optimized through multi-objective optimization of power and heating load. The outcomes of this optimization process revealed that the optimal values for electric power and heating load are 507.34 kW and 261.94 kW, respectively. Additionally, the capacity of freshwater obtained of about 0.076 kg/s. The optimal solution also showcased an exergy efficiency of 44.93 % and a relatively short payback period of 4.68 years, indicating the system's cost-effectiveness and favorable performance.

System Design, Optimization and 2nd Law Analysis of a 100 MWe Double Reheat s-CO2 Power Plant at Full Load and Part Loads

Super-critical Carbon dioxide (s-CO2) power plants are considered to be efficient and environmentally friendly compared to the traditional Rankine cycle-based steam power plants and Brayton cycle-based gas turbine power plants. In this work, the system design of a coal-fired 100 MWe double reheat s-CO2 power plant is presented. The system is also optimized for efficiency with turbine inlet pressures and the recompression ratio as the variables. The components needed, mass flow rates of various streams and their pressures at various locations in the system have been established. The plant has been studied based on 1st and 2nd laws at full load and at part loads of 80%, 60% and 40%. Operating parameters such as mass flow rate, pressure and temperature have considerably changed in comparison to full load operation. It was also observed that the 1st law efficiency is 53.96%, 53.93%, 52.63% and 50% while the 2nd law efficiency is 51.88%, 51.86%, 50.61% and 48.1% at 100%, 80%, 60% and 40% loads, respectively. The power plant demonstrated good performance even at part loads, especially at 80% load, while the performance deteriorated at lower loads. At full load, the highest amount of exergy destruction is found in the main heater (36.6%) and re-heaters (23.2% and 19.6%) followed by the high-temperature recuperator (5.7%) and cooler (4.1%). Similar trends were observed for the part load operation. It has been found that the recompression ratio should be kept high (>0.5) at lower loads in order to match the performance at higher loads. Combustion and heat exchange due to finite temperature differences are the main causes of exergy destruction, followed by pressure drop.

Performance Analysis and Optimization of Regenerative Gas Turbine Power Plant using RSM

In the present study, a thermodynamic analysis of thermal performance is carried out in a regenerative GT power plant. The optimization procedure of design parameters is realized by the response surface methodology (RSM). The thermodynamic simulations were carried out using the EES code for numerous variables such as compression ratio (2≤rp≤12), inlet temperature (273≤T1≤313K), turbine inlet temperature (1200≤T3≤1600K), and regenerator effectiveness (45≤ε≤85%). Analysis of variance (ANOVA) was carried out to identify the process parameters that influence thermal efficiency (ηth) and specific fuel consumption (SFC). Then, a second-order regression model was developed to correlate the process parameters with ηth and SFC. Consequently, numerical and graphical optimizations were performed to achieve multi-objective optimization for the desired criteria. According to the desirability function approach, it can be seen that the optimum objective functions are ηth=50.61% and SFC=0.117 kg/kWh, corresponding to process parameters T1=273.26K, T3=1597.64K, rp=6.95 and ε=84.89%. Lastly, verification simulations were conducted to validate the importance of the generated statistical models.

Enhancing Gas Turbine Power Plant Performance in Tropical Climates by Using Inlet Air Cooling with Desiccant Dehumidification and Evaporative Cooling

Abstract Gas turbine power plants play a crucial role in meeting the growing demand for electrical energy. However, their performance can be hindered by high ambient temperatures and humidity levels in tropical climates, leading to a drop in power output. This study investigates the potential benefits of using inlet air cooling with desiccant dehumidification and evaporative cooling to improve the performance of gas turbine power plants in tropical regions. The results show that this inlet air cooling method, integrating evaporative cooling, desiccant wheel, and Maisotsenko cooler, is a viable alternative for mitigating the performance decrease of gas turbines in hot tropical conditions. Furthermore, the compressor inlet temperature can be reduced on average by 11.5 °C by using turbine exhaust gases to heat the regeneration air utilized in the desiccant wheel for dehumidification. Additionally, the power requirement of the inlet air cooling system amounts to around 0.9 MW compared with an improvement of more than 2 MW in power output at peak temperature. Further research is needed to understand and quantify other benefits related to inlet air cooling, such as reducing emissions of harmful pollutants and operating at higher turbine inlet temperatures.

A novel inlet air cooling system to improve the performance of intercooled gas turbine combined cycle power plants in hot regions

In hot climates, the entry of high-temperature air into the compressor of intercooled gas turbine power plants (IcGTCC) can lead to reduced electricity production during peak demand periods. To address this issue, this study proposes a novel inlet air cooling (IAC) system for improving the performance of IcGTCC in hot regions. This system utilizes waste heat from the intercooler to cool the compressor's inlet air via absorption chillers. The performance of this system was evaluated and compared to four popular IAC technologies: evaporative cooling, solar-powered absorption cooling, steam-operated absorption cooling, and vapor compression cooling. Additionally, the expected annual profit and payback period were estimated. Results show that the proposed IAC system resolves the drawbacks of IcGTCC in hot regions, increasing the power output by 19% and the overall efficiency by 2.3%. It is estimated that the proposed IAC system can improve plant efficiency by 8–18% compared to literature designs, leading to higher annual profits (66% and 10% higher than steam and mechanical cooling systems, respectively). Moreover, it has a short payback period of 1.74 years, which is 3%, 67%, and 85% shorter than mechanical, steam, and solar cooling systems, respectively, making it a highly cost-effective solution.

Coupling a Gas Turbine Bottoming Cycle Using CO2 as the Working Fluid with a Gas Cycle: Exergy Analysis Considering Combustion Chamber Steam Injection

Gas turbine power plants have important roles in the global power generation market. This paper, for the first time, thermodynamically examines the impact of steam injection for a combined cycle, including a gas turbine cycle with a two-stage turbine and carbon dioxide recompression. The combined cycle is compared with the simple case without steam injection. Steam injection’s impact was observed on important parameters such as energy efficiency, exergy efficiency, and output power. It is revealed that the steam injection reduced exergy destruction in components compared to the simple case. The efficiencies for both cases were obtained. The energy and exergy efficiencies, respectively, were found to be 30.4% and 29.4% for the simple case, and 35.3% and 34.1% for the case with steam injection. Also, incorporating steam injection reduced the emissions of carbon dioxide.