Kind Of Power Plant Research Articles

Study on the water vapor adsorption Characteristics of Carbon materials in HTGR

High-temperature gas-cooled reactor (HTGR) is the first kind of power plant with fourth-generation features in the world, and a large amount of graphite and carbon material is adopted as structural material and fuel matrix material, including boron-containing carbon (BC) and isostatic pressure graphite (IG-110). As a kind of porous material, the carbon material contains a certain amount of moisture, which will impose negative effects on reactor safety. Therefore, this paper studies the water vapor adsorption characteristics of carbon materials in HTGR. The adsorption isotherms of BC and IG-110 were obtained by experimental measurements. Experiments show that the moisture adsorption of IG-110 is much lower than that of BC at various relative humidity. The experimental data is analysed by the BET, GAB, DA, Oswin adsorption models.

Thermo-Economic Assessment Under Electrical Market Uncertainties of a Combined Cycle Gas Turbine Integrated With a Flue Gas-Condensing Heat Pump

Abstract Renewable energy penetration is growing, due to the target of greenhouse-gas-emission reduction, even though fossil fuel-based technologies are still necessary in the current energy market scenario to provide reliable back-up power to stabilize the grid. Nevertheless, currently, an investment in such a kind of power plant might not be profitable enough, since some energy policies have led to a general decrease of both the average single national price of electricity (PUN) and its variability; moreover, in several countries, negative prices are reached on some sunny or windy days. Within this context, combined heat and power (CHP) systems appear not just as a fuel-efficient way to fulfill local thermal demand but also as a sustainable way to maintain installed capacity able to support electricity grid reliability. Innovative solutions to increase both the efficiency and flexibility of those power plants, as well as careful evaluations of the economic context, are essential to ensure the sustainability of the economic investment in a fast-paced changing energy field. This study aims to evaluate the economic viability and environmental impact of an integrated solution of a cogenerative combined cycle gas turbine power plant with a flue gas condensing heat pump. Considering capital expenditure, heat demand, electricity price, and its fluctuations during the whole system life, the sustainability of the investment is evaluated taking into account the uncertainties of economic scenarios and benchmarked against the integration of a cogenerative combined cycle gas turbine power plant with a heat-only boiler (HOB).

Study of power flow and stability for a hybrid diesel-PV power system in Indonesia

Diesel power plants are still the main choice for supplying isolated grids in Indonesia. Although this kind of power plant is easy to install, it has a high cost of energy (COE) mainly due to the cost of diesel fuel. Besides, Indonesia as a tropical country has a high intensity of solar radiation. Moreover, the investment cost of PV power plant is getting lower and it does not require high operation cost. Thus, the implementation of PV power plant is considered promising in Indonesia, and the idea of combining diesel power plants with PV in isolated grids arises to increase the efficiency of the COE. Apart from the economical aspect, the technical aspect of a hybrid diesel-PV power system implementation needs to be studied as well. In this study, the impact of the PV power plant interconnection to the existing grid is analysed in terms of the power flow and the transient stability using the DIgSILENT PowerFactory software. Furthermore, a load-sharing scheme is applied to some diesel generator units. According to the simulation result, the hybrid power system operated within the allowable voltage limits. After some transient events occurred, the hybrid power system was able to maintain its stability.

Geotechnical Characteristics of Tanjung Bin Coal Bottom Ash

Coal is considered one of the major sources of power-generation in Malaysia. The Coal-fired power plant is a kind of power plant that uses coal to generate electricity. The globally increasing demand for energy has led to an increase in the number of installation of coal-fired power plants. With the growth in coal-burning power plants, massive amounts of coal bottom ash have been produced as waste material. This article presents an experimental study on the geotechnical characteristics of Tanjung bin coal bottom ash and compares them with the properties of the natural granular soil focusing on the physical and mechanical characteristics namely; grain size distribution, specific gravity, compaction, permeability, shear strength, and relative density. Results revealed that the Tanjung bin bottom ash has geotechnical properties similar to the natural granular material, therefore it can be utilized as a substitute material to sand in several geotechnical application.

Comparative Modeling of a Parabolic Trough Collectors Solar Power Plant with MARS Models

Power plants producing energy through solar fields use a heat transfer fluid that lends itself to be influenced and changed by different variables. In solar power plants, a heat transfer fluid (HTF) is used to transfer the thermal energy of solar radiation through parabolic collectors to a water vapor Rankine cycle. In this way, a turbine is driven that produces electricity when coupled to an electric generator. These plants have a heat transfer system that converts the solar radiation into heat through a HTF, and transfers that thermal energy to the water vapor heat exchangers. The best possible performance in the Rankine cycle, and therefore in the thermal plant, is obtained when the HTF reaches its maximum temperature when leaving the solar field (SF). In addition, it is necessary that the HTF does not exceed its own maximum operating temperature, above which it degrades. The optimum temperature of the HTF is difficult to obtain, since the working conditions of the plant can change abruptly from moment to moment. Guaranteeing that this HTF operates at its optimal temperature to produce electricity through a Rankine cycle is a priority. The oil flowing through the solar field has the disadvantage of having a thermal limit. Therefore, this research focuses on trying to make sure that this fluid comes out of the solar field with the highest possible temperature. Modeling using data mining is revealed as an important tool for forecasting the performance of this kind of power plant. The purpose of this document is to provide a model that can be used to optimize the temperature control of the fluid without interfering with the normal operation of the plant. The results obtained with this model should be necessarily contrasted with those obtained in a real plant. Initially, we compare the PID (proportional–integral–derivative) models used in previous studies for the optimization of this type of plant with modeling using the multivariate adaptive regression splines (MARS) model.

New Fuel Air Control Strategy for Reducing NOx Emissions from Corner-Fired Utility Boilers at Medium–Low Loads

Due to the rapidly growing renewable power, the fossil fuel power plants have to be increasingly operated under large and rapid load change conditions, which can induce various challenges. This work aims to reduce NOx emissions of large-scale corner-fired boilers operated at medium–low loads. The combustion characteristics and NOx emissions from a 1000 MWe corner-fired tower boiler under different loads are investigated experimentally and numerically. A new control strategy for the annular fuel air is proposed and implemented in the boiler, in which the secondary air admitted to the furnace through the air annulus around each coal nozzle tip is controlled by the boiler load, instead of being controlled by the output of the connected mill as commonly used in this kind of power plant. Both the experimental and simulation results show that the new control strategy reduces NOx emissions at the entrance of the selective catalytic reduction (SCR) system by about 20% at medium–low loads, compared to those based ...

ANALISIS PENGARUH INTERKONEKSI DISTRIBUTED GENERATION (PLTSA SUWUNG) TERHADAP RUGI-RUGI DAYA DAN KEANDALAN PADA PENYULANG SERANGAN

The distributed generation technology or in this case abbreviated DG is a kind of power plants with small scale which prioritizes the utilization of renewable energy resources such as wind, water, solar, geothermal, ocean waves (Wave Energy), ocean currents (Ocean Current Energy), biomass, and biogass to produce the electrical energy with range of power generation between 1 kW-10 MW. One of the DG in Bali and still in operation is the garbage power plant which located in Suwung, South Denpasar. An analysis has been done using load flow analysis and reliability assessment to determine the effect of DG interconnection against the power losses and the level of reliability on the Serangan feeder. Based on the research that has been done, DG intercon-nection on the Serangan feeder decrease the power losses and increase the reliability and it can visible from the acquisition of SAIFI and SAIDI index which decreased. The best location of DG interconnection to get low of the power losses and the high level of reliability is at 97% from the total length of the feeder. At that location the power losses is decrease as big as 4.5 kW or 11.25% of the total power lossess without the DG interconnection and decrease of the SAIFI and SAIDI index respectively to 0.1 failure/customers/year and 1.4150 hour/ customer/year

Environmental Assessment of Renewable Fuel Energy Systems with Cross-Media Effects Approach

In the last years, the number of installed biofuels power plants is increased in northern Italy, due to favorable legislation on renewable energy sources, posing the issue to assess the resulting environmental effects. The European legislation on emissions for renewable fuels power plants provides guidelines to be integrated in the local regulations; moreover, local authorities have to identify the critical power plants in terms of pollution and the key parameters to grant licenses for the future plants.The aim of this paper is to describe a methodology and the calculation routine developed to assess the environmental effects of biomass plants in terms of simple indexes. The used approach is based on the Cross-Media Effects described by a European Commission Reference Document. In particular, several indexes are introduced to cover the most relevant environmental effects, as: air toxicity, global warming, acidification, eutrophication and photochemical ozone creation. For every considered pollutant (such as NOx, CO, etc.) directly emitted by the power plant, specific factors have been identified, in order to calculate the contribution to the different environmental indexes. Finally, a numerical evaluation of different biomass power plants, installed in Emilia Romagna region, is provided, in order to assess their environmental cross-media potential and to compare such kind of power plants with large scale, fossil-fuelled power plants.

A coherent integration of design choices for advancing in solar thermal power

Results from a systematic research on the coherence (and inefficiencies) of current and alternative ways to exploit solar thermal energy are reported in this paper, intended to analyze forth and back the energy conversion chain from solar radiation to electricity. This exercise pointed out the pivotal role of the heat transfer fluid for an effective integration of said energy chain, and CO2 was selected for that role, because it is a gas without practical limitations in maximum temperature, and very adequate values of critical temperature and pressure. Optimum operating conditions were attainable in multi-tube receivers illuminated by advanced Linear Fresnel Reflectors with moderate values of radiation concentration factors; and the architecture of the full solar field system could be simplified in modular lattices leading to minimum values of mass requirements of the relevant materials, from glass to concrete. The specific investment cost for this new kind of power plant was evaluated in terms of said mass accountancy, and it was found that solar thermal power could be competitive with fossil fuel power plants in the near future.

Molten carbonate fuel cells for CO2 separation and segregation by retrofitting existing plants – An analysis of feasible operating windows and first experimental findings

Molten carbonate fuel cells (MCFC) used as active carbon dioxide concentrator units are a promising solution to reduce greenhouse gas (GHG) emissions from traditional combustion plants. The cell reaction transfers carbonate ions from the cathode to the anode and allows the fuel cell to simultaneously produce power and separate CO2 from a stream of flue gas. Carbon dioxide separation is of high interest for use in natural gas combined cycles and coal gas combustion plants, as a large part of anthropogenic CO2 worldwide originates from such installations. The flue gas from these types of combustion technologies typically contains 3–15% CO2, which is in the lower operational range of the MCFC. The aim of this work was to investigate the possibility to retrofit existing power plants with MCFC to reduce the total release of CO2 without necessarily reducing the power output, and to understand which kind of power plant could have the major benefits with an MCFC retrofitting. The performance of lab scale MCFC fed with simulated flue gas was evaluated, and a number of operational parameters, such as utilization factor and cathode humidification were varied to study the effect on fuel cell performance. The results show that it is feasible to operate the MCFC as a CO2 separator for simulated gas turbine flue gas; however, the voltage drop due to low CO2 concentration may restrict the operating window depending on various operating conditions.

Simulating Ocean and Tidal Current Power Plants with Homer

The oceans can provide us with several direct sources of renewable energy, such as wave energy, energy from currents and energy in thermal gradients among other energy resources. The uses of these resources have not yet reached technical and economic maturity, but they have experienced significant advances in recent years. In this process, tools for feasibility analysis of hybrid systems including specific power plants are important. This article is dedicated to the feasibility study of hybrid systems containing power plants based on the energy of ocean and tidal currents. The software currently available for feasibility studies do not present specific models already developed for the simulation of this kind of power plants. Thus, this technical note shows how Homer software (Legacy version) can be used to conduct this type of study in pre-feasibility level. This article also presents a case study in which Homer is applied, focused only on Homer adaptation but without exhausting the subject, showing a feasibility window that would include current power plants with certain cost and efficiency in an existing PV wind biodiesel hybrid system.

On the effects of windbreaks on the aerodynamic loads over parabolic solar troughs

Parabolic reflectors, also known as parabolic troughs, are widely used in solar thermal power plants. This kind of power plants is usually located on desert climates, where the combined action of wind and dust can be of paramount importance. In some cases it becomes necessary to protect these devices from the joined wind and sand action, which is normally accomplished through solid windbreaks. In this paper the results of a wind tunnel test campaign, of a scale parabolic trough row having different windward windbreaks, are reported. The windbreaks herein considered consist of a solid wall with an upper porous fence. Different geometrical configurations, varying the solid wall height and the separation between the parabolic trough row and the windbreak have been considered. From the measured time series, both the mean and peak values of the aerodynamic loads were determined. As it would be expected, mean aerodynamic drag, as well as peak values, decrease as the distance between the windbreak and the parabolic increases, and after a threshold value, such drag loads increase with the distance.

Optimal Training Algorithm Application to Design an Associative Memory for Fault Diagnosis at a Fossil Electric Power Plant

This paper presents the development and application of a neural networks-based scheme for fault diagnosis, including detection and classification, for the steam generator of a fossil electric power plant. The scheme is constituted by two components: residual generation and fault classification. The first component generates residuals via the difference between measurements coming from the plant and a neural network predictor. The neural network predictor is trained with healthy data collected from a full-scale simulator reproducing reliably the process behavior. For the second component detection thresholds are used to encode the residuals as bipolar vectors which represent fault patterns. The fault patterns are stored in an associative memory based on a recurrent neural network which is trained via optimal training algorithm. The scheme is evaluated on-line via a full-scale simulator to diagnose the main faults appearing in this kind of power plants when load power is constant and when the operator is carrying out load power changes. Furthermore, the fault diagnosis strategy is be able to distinguish when the operator is carrying out load power changes free of fault as normal operating conditions.

FAULT DIAGNOSIS FOR A STEAM GENERATOR VIA RECURRENT NEURAL NETWORKS

This paper presents the development and application of a neural networks-based scheme for fault diagnosis, including detection and classification, for the steam generator of a fossil electric power plant. The scheme is constituted by two components: residual generation and fault classification. The first component generates residuals via the difference between measurements coming from the plant and a neural network predictor. The neural network predictor is trained with healthy data collected from a full-scale simulator reproducing reliably the process behavior. For the second component detection thresholds are used to encode the residuals as bipolar vectors which represent fault patterns. The fault patterns are stored in an associative memory based on a recurrent neural network. The scheme is evaluated on-line via a full-scale simulator to diagnose the main faults appearing in this kind of power plants.

MODELLING AND OPTIMIZATION OF A MICRO COMBINED HEAT AND POWER PLANT

Most electrical power in developed countries today is produced by large centralized power plants. With the technology progress, micro combined heat and power generators (ranging from 1 to 10 kW) are becoming available. Tomorrow, they will produce electricity and heat at home, locally. This paper presents a method of handling these new kind of power plants. The solution based on dynamic programming schedules the use of the micro CHP and of the hot water tank in order to minimize the operating costs. An on-line implementation of the algorithm is proposed and tested on a validation model.