Numerical Investigation of Thermoelectric Topping Cycle in Coal Fired Power Plant Boiler

2016 ◽  
Author(s):  
Armin Silaen ◽  
Bin Wu ◽  
Chenn Zhou
Keyword(s):  
Power Generation ◽  
Electrical Power ◽  
Flame Temperature ◽  
Three Dimensional ◽  
Rankine Cycle ◽  
Generation Process ◽  
Steam Turbines ◽  
Steam Temperature ◽  
Low Efficiency ◽  
Topping Cycle

Traditional fossil fuel power generation process typically has low efficiency. Large amount of the energy loss in Rankine cycle steam turbines (ST) is due to the temperature difference between the combustion flame temperature ∼2250 K (adiabatic) and the high pressure steam temperature up to 900 K. This paper investigates the potential of harvesting this energy to produce additional electrical power using solid-state thermoelectric (TE) power generators placed into the gap between the flame temperature and the steam temperature. Three dimensional (3D) numerical model of a simplified TE module is developed. Different dimensions of fin added to the TE module were investigated to maximize the additional electrical power generation without sacrificing the boiler efficiency.

Numerical Model of Thermoelectric Topping Cycle of Coal Fired Power Plant

2013 ◽  
Author(s):  
Armin Silaen ◽  
Bin Wu ◽  
Dong Fu ◽  
Chenn Zhou ◽  
Kazuaki Yazawa ◽  
...  
Keyword(s):  
Power Plant ◽  
Numerical Model ◽  
Electrical Power ◽  
Flame Temperature ◽  
Rankine Cycle ◽  
Generation Process ◽  
Steam Turbines ◽  
Gas Temperature ◽  
Steam Temperature ◽  
Low Efficiency

Traditional fossil fuel power generation process typically has low efficiency. Large amount of the energy loss in Rankine cycle steam turbines (ST) is due to the temperature difference between the combustion flame temperature ∼2250 K (adiabatic) and the high pressure steam temperature up to 900 K. However, some of this energy can be harvested using solid-state thermoelectric (TE) power generators which are placed into the gap between the flame temperature and the steam temperature that produce additional electrical power. This study investigates the potential placement of TE on water tube wall inside a boiler at a coal fired power plant. Three dimensional (3D) numerical model of a simplified TE module is developed and hot gas temperature and steam temperature from the boiler are used as boundary conditions at the hot side and cold side of the TE. The numerical results are compared with analytical calculations. The 3D effects of the thermal spreading in the TE module are investigated. Parameters such as TE leg cross-section area and TE fill factor are examined in order to maximize the electrical power production of the TE without sacrificing the boiler efficiency (i.e., reducing the steam temperature). The study also looks into the various locations inside the boiler that have good potential for TE installation.

Numerical Model of Thermoelectric Topping Cycle of Coal-Fired Power Plant

2015 ◽  
Vol 137 (9) ◽  
Author(s):  
Armin K. Silaen ◽  
Bin Wu ◽  
Chenn Zhou ◽  
Kazuaki Yazawa ◽  
Ali Shakouri
Keyword(s):  
Power Plant ◽  
Numerical Model ◽  
Electrical Power ◽  
Flame Temperature ◽  
Rankine Cycle ◽  
Generation Process ◽  
Steam Turbines ◽  
Gas Temperature ◽  
Steam Temperature ◽  
Low Efficiency

Traditional fossil fuel power generation process typically has low efficiency. Large amount of the energy loss in Rankine cycle steam turbines (ST) is due to the temperature difference between the combustion flame temperature ∼2250 K (adiabatic) and the high pressure steam temperature up to 900 K. However, some of this energy can be harvested using solid-state thermoelectric (TE) power generators which are placed into the gap between the flame temperature and the steam temperature that produce additional electrical power. This study investigates the potential placement of TE on water tube wall inside a boiler at a coal-fired power plant. Three-dimensional (3D) numerical model of a simplified TE module is developed, and hot gas temperature and steam temperature from the boiler are used as boundary conditions at the hot side and cold side of the TE. The numerical results are compared with analytical calculations. The 3D effects of the thermal spreading in the TE module are investigated. Parameters such as TE leg cross section area and TE fill factor are examined in order to maximize the electrical power production of the TE without sacrificing the boiler efficiency (i.e., reducing the steam temperature). The study also looks into the various locations inside the boiler that have good potential for TE installation.

Thermodynamic and Performance Study of Solar Regenerative Organic Rankine Cycle System for Use in Residential Micro-Combined Heat and Power Generation

2019 ◽  
Author(s):  
Wahiba Yaïci ◽  
Evgueniy Entchev
Keyword(s):  
Power Generation ◽  
Energy Demand ◽  
Waste Heat ◽  
Residential Buildings ◽  
Electrical Power ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Combined Heat And Power ◽  
Energy Sources ◽  
Performance Study

Abstract A continued increase in both energy demand and greenhouse gas emissions (GHGs) call for utilising energy sources effectively. In comparison with traditional energy set-ups, micro-combined heat and power (micro-CHP) generation is viewed as an effective alternative; the aforementioned system’s definite electrical and thermal generation may be attributed to an augmented energy efficiency, decreased capacity as well as GHGs percentage. In this regard, organic Rankine cycle (ORC) has gained increasing recognition as a system, which is capable for generating electrical power from solar-based, waste heat, or thermal energy sources of a lower quality, for instance, below 120 °C. This study focuses on investigating a solar-based micro-CHP system’s performance for use in residential buildings through utilising a regenerative ORC. The analysis will focus on modelling and simulation as well as optimisation of operating condition of several working fluids (WFs) in ORC in order to use a heat source with low-temperature derived from solar thermal collectors for both heat and power generation. A parametric study has been carried out in detail for analysing the effects of different WFs at varying temperatures and flowrates from hot and cold sources on system performance. Significant changes were revealed in the study’s outcomes regarding performance including efficiency as well as power obtained from the expander and generator, taking into account the different temperatures of hot and cold sources for each WF. Work extraction carried out by the expander and electrical power had a range suitable for residential building applications; this range was 0.5–5 kWe with up to 60% electrical isentropic efficiency and up to 8% cycle efficiency for 50–120 °C temperature from a hot source. The operation of WFs will occur in the hot source temperature range, allowing the usage of either solar flat plate or evacuated tube collectors.

Research on China's First Residential Grid-Connected Photovoltaic System

2013 ◽  
Vol 392 ◽  
pp. 563-567
Author(s):  
Yan Jie Dai ◽  
Chun Yan Sun ◽  
Xiao Yong Wang ◽  
Wei Hua Yang
Keyword(s):  
Power Generation ◽  
Power Quality ◽  
Electrical Power ◽  
Photovoltaic System ◽  
Pv System ◽  
Quality Analyzer ◽  
Low Efficiency ◽  
Power Metering ◽  
Pv Power Generation ◽  
Power Standard

Along with the continuous expansion of photovoltaic (PV) power generation, different capacity of grid connected PV system is gradually increased. China's first residential grid-connected PV system has interconnected successfully in QingDao and operated normally. This document analyzed electrical connected diagram of grid-connected PV system. Using power quality analyzer, the online power quality is monitored and analyzed. When PV power generation is low efficiency of operating state, harmonic current is over distortion limits. Monitoring data was simulated through electrical power standard source. To ensure power metering accuracy under harmonic, the watt-second method is proposed. Testing results show that smart electrical meter can meter accurately within 20 times harmonics.

Supercritical Fluids and Their Applications in Power Generation

2021 ◽  
pp. 566-599
Author(s):  
Huijuan Chen ◽  
Ricardo Vasquez Padilla ◽  
Saeb Besarati
Keyword(s):  
Power Generation ◽  
Supercritical Fluids ◽  
Waste Heat ◽  
Electrical Power ◽  
Rankine Cycle ◽  
Low Grade ◽  
Heat Sources ◽  
Working Fluids ◽  
Low Grade Heat ◽  
Selection Of

Supercritical fluids have been studied and used as the working fluids in power generation system for both high- and low-grade heat conversions. Low-grade heat sources, typically defined as below 300 ºC, are abundantly available as industrial waste heat, solar thermal, and geothermal, to name a few. However, they are under-exploited for power conversion because of the low conversion efficiency. Technologies that allow the efficient conversion of low-grade heat into mechanical or electrical power are very important to develop. First part of this chapter investigates the potential of supercritical Rankine cycles in the conversion of low-grade heat to power, while the second part discusses supercritical fluids used in higher grade heat conversion system. The selection of supercritical working fluids for a supercritical Rankine cycle is of key importance. This chapter discusses supercritical fluids fundamentals, selection of supercritical working fluids for different heat sources, and the current research, development, and commercial status of supercritical power generation systems.

Modeling and Control of Excitation Systems for Synchronous Generators

2011 ◽  
Vol 148-149 ◽  
pp. 983-986
Author(s):  
Farouk Naeim ◽  
Sheng Liu ◽  
Lan Yong Zhang
Keyword(s):  
Power Generation ◽  
Power Plant ◽  
Electrical Power ◽  
Control Element ◽  
Steam Turbines ◽  
Synchronous Generators ◽  
Power Station ◽  
Modeling And Control ◽  
Generation Cost ◽  
And Control

The electrical power generation and distribution in power plant suffers from so many problems, such as instability of demand and generation. These lead to increase of generation cost. The system under consideration is consist of two steam turbines each of 30 MW with total of 60 MW (2*30). The excitation system of 30 MW generators has been chosen, due to the problems faced by operators in power station. These problems include aging of the control element, feeding back signal and loading increase/ decrease problems.

scholarly journals Biomass Gasification for Power Generation: A Comparison with Steam Boilers in the Brazilian Scenario

Engevista ◽  
2017 ◽  
Vol 19 (2) ◽  
pp. 306 ◽  
Author(s):  
João Miguel ◽  
Tiberio Filho ◽  
Ricardo Pereira ◽  
Aymer Maturana
Keyword(s):  
Power Generation ◽  
Sugar Cane ◽  
Electrical Power ◽  
Cost Effective ◽  
Biomass Gasification ◽  
Political Support ◽  
Direct Combustion ◽  
Steam Boilers ◽  
Low Efficiency ◽  
Framework Conditions

This work compares biomass gasification and conventional direct combustion in steam boilers for producing power in the context of Brazilian sugar cane mills. The objective of this technical report is to show that gasification could be a more attractive way to convert biomass in energy, compared to using steam boilers, which in some cases can show a low efficiency.  The idea is to use the gasifiers in sugarcane mills that have low pressure boilers (21 to 42 kgf/cm2) that are currently dedicated only to generate steam or electrical power for the mill own energy consumption. The results shows that gasification could be a cost-effective alternative for power production in Brazilian sugar cane plants with some additional advantages like the bagasse usage between the season and off-season periods to maintain a constant power generation throughout the entire year, higher energy availability and efficiency. However, nowadays in Brazil the economic advantage of gasification depends highly on political support and reliable long-term stable political framework conditions with an enough timeframe for the development, construction and operation of biomass gasification plants.  

Electrical Power Generation: Fossil Fuels

2017 ◽  
Author(s):  
Peter Rez
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Power Plants ◽  
Fossil Fuels ◽  
Turbine Blades ◽  
Electrical Power ◽  
Rankine Cycle ◽  
Combined Cycle ◽  
Brayton Cycle ◽  
Steam Temperature

Nearly all electrical power is generated by rotating a coil in a magnetic field. In most cases, the coil is turned by a steam turbine operating according to the Rankine cycle. Water is boiled and heated to make high-pressure steam, which drives the turbine. The thermal efficiency is about 30–35%, and is limited by the highest steam temperature tolerated by the turbine blades. Alternatively, a gas turbine operating according to the Brayton cycle can be used. Much higher turbine inlet temperatures are possible, and the thermal efficiency is higher, typically 40%. Combined cycle generation, in which the hot exhaust from a gas turbine drives a Rankine cycle, can achieve thermal efficiencies of almost 60%. Substitution of coal-fired by combined cycle natural gas power plants can result in significant reductions in CO2 emissions.

scholarly journals Effective Power Transmission By Means of Air Compressor, Air Turbine System and Solar Concentrators

2021 ◽  
Vol 10 (5) ◽  
pp. 411-415
Author(s):  
Harikrishnan R ◽  
K.C James
Keyword(s):  
Power Generation ◽  
Power Plants ◽  
Power Transmission ◽  
Electrical Power ◽  
Combined Cycle ◽  
Generation Process ◽  
Effective Power ◽  
Air Compressor ◽  
Load Power ◽  
Air Turbine

Usually Electrical Power is generated in large scale using Air Compressors and Gas Turbine Systems. This type of Power plants is usually used as Peak load Power Plants. These Power Plants can assist in various power generation process along with base load power plants like Thermal Power Plants, Combined cycle power plants etc. Here in this Research paper, a new method of Power generation is being discussed. It utilizes an Air Compressor-Air Turbine System for Electrical Power generation by means of effective power transmission. This method is simple and less costly. It requires less space and less skilled laborer. It can be used in Stand by and Emergency power generation systems. An ANN model is carried out which gives satisfactory working conditions. The cost analysis is being carried out by considering small capacity and micro power production conditions. The efficiency attained during this method of power generation is around 55%. By incorporating large macro energy systems, we can produce more power output and also generate more electrical power. By considering all these factors it can be considered as a very good working model.

A Highly Efficient Combined Cycle Fossil and Biomass Fuel Cell Power Generation and Hydrogen Production Plant With Zero CO2 Emission

2004 ◽  
Author(s):  
Meyer Steinberg
Keyword(s):  
Power Generation ◽  
Fuel Cell ◽  
Elemental Carbon ◽  
Hydrogen Plasma ◽  
Electrical Power ◽  
Rankine Cycle ◽  
Combined Cycle ◽  
Water Gas Shift ◽  
Direct Carbon Fuel Cell ◽  
Water Gas

An advanced combined cycle for fossil and biomass fuel power generation and hydrogen production is described. An electric arc hydrogen plasma black reactor (HPBR) decomposes the carbonaceous fuel (natural gas, oil, coal and biomass) to elemental carbon and hydrogen. When coal and biomass feedstocks are used, the contained oxygen converts to carbon monoxide. Any ash and sulfur present are separated and removed. The elemental carbon is fed to a molten carbonate direct carbon fuel cell (DCFC) to produce electrical power, part of which is fed back to power the hydrogen plasma. The hydrogen produced is used in a solid oxide fuel (SOFC) cell for power generation and the remaining high temperature energy in a back-end steam Rankine cycle (SRC) for additional power. Any CO formed is converted to hydrogen using a water gas shift reactor. The plasma reactor is 60% process efficient, the direct carbon fuel cell is up to 90% thermally efficient, the solid oxide fuel cell is 56% efficient and the steam Rankine cycle is 38% efficient. Depending on the feedstock, the combined cycles have efficiencies ranging from over 70% to exceeding 80% based on the higher heating value of the feedstock and are thus twice as high as conventional plants. The CO2 emissions are proportionately reduced. Since the CO2 from the direct carbon fuel cell and the water gas shift is highly concentrated, the CO2 can be sequestered to reduce emission to zero with much less energy loss than required by conventional plants. Alternatively, the combined cycle plants can produce hydrogen for the FreedomCAR program in combination with electrical power production at total thermal efficiencies greater than obtained with fossil fuel reforming and gasification plants producing hydrogen alone.

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