Coal-fired Electric Plants Research Articles

PREDICTION OF CARBON DIOXIDE EMISSION FROM ELECTRICITY GENERATION IN ASEAN

The Coal-Fired Power Plants with low-emissions plants in the power sector can avoid nearly 800 million tonnes CO2 by 2030. The number of populations, Gross Domestic Product (GDP), electricity generation, NDC, and relevant energy policies influenced the prediction of Carbon Dioxide (CO2) emission from electricity generation. Aim: The objective is to analyze trends of CO2 growth related to electricity generation activities from countries in ASEAN with an emphasis on identifying the factors that influence it and evaluating the effectiveness of existing decarbonization policies in AMS and developing suitable strategies to reduce future CO2 emissions. Methodology and Result: Predicting CO2 emissions is conducted using three approaches by considering the newest NDC and energy policies, conducted by descriptive and quantitative analysis based on secondary data of (1) general information on ASEAN Member States (AMS), (2) information on power plants, (3) information on fuel use in electricity generation, and (4) decarbonization policies in AMS. Results indicated that the availability of potential energy sources (coal/oil/gas/RE) influences the dominant energy used in AMS Prediction of CO2e emission in the 2020 to 2040 period identified Vietnam as one of the highest CO2e emitters (380,1 Mt CO2e) in the electricity sector by 2030. Conclusion, significance and impact study: AMS needs to make a more aggressive energy policy to reduce CO2 level significantly, achieving the 2050 net zero transition targets. Ultimately, the shifting from coal-fired electricity plants to other fuel sources with a lower emission factor proves to be the most significant factor towards emission reduction.

Sustainable Alternatives for Green Mortar: Quarry Waste and Ultra high fly ash utilization

The use of waste materials from different industries as a replacement of cement has gained much attention all over the world. In addition, many attempts have been done to replace partially or totally one of the ingredients from the mix design to lower the negative impacts of construction industry. In this study, quarry waste and fly ash were used as two different sustainable approaches to replace the maximum volume of natural alluvial sand and cement, respectively, in the traditional mortar matrix. The quarry waste is a by-product of quarries characterized with a large volume of fines, whereas, fly ash is the by-product of coal-fired electric generation plants. The performance of the green mortars containing the maximized volume of quarry waste and fly ash were evaluated with regard to the mechanical properties. The results have clearly indicated the beneficial use of the quarry waste and fly ash as a substitute for siliceous sand and cement respectively in preparation of green mortars. In addition, the cost and parametric analysis was also performed for a multi-story reinforced concrete building using the designed quarry sand and fly ash as concrete ingredients.

Cathodic Activation of Titania-Fly Ash Cenospheres for Efficient Electrochemical Hydrogen Production: A Proposed Solution to Treat Fly Ash Waste

Fly ash (FA) is a waste product generated in huge amounts by coal-fired electric and steam-generating plants. As a result, the use of FA alone or in conjunction with other materials is an intriguing study topic worth exploring. Herein, we used FA waste in conjunction with titanium oxide (TiO2) to create (FA-TiO2) nanocomposites. For the first time, a cathodic polarization pre-treatment regime was applied to such nanocomposites to efficiently produce hydrogen from an alkaline solution. The FA-TiO2 hybrid nanocomposites were prepared by a straightforward solvothermal approach in which the FA raw material was mixed with titanium precursor in dimethyl sulfoxide (DMSO) and refluxed during a given time. The obtained FA-TiO2 hybrid nanocomposites were fully characterized using various tools and displayed a cenosphere-like shape. The synthesized materials were tested as electrocatalysts for the hydrogen evolution reaction (HER) in 0.1 M KOH solution in the dark, employing various electrochemical techniques. The as-prepared (unactivated) FA-TiO2 exhibited a considerable HER electrocatalytic activity, with an onset potential (EHER) value of −144 mV vs. RHE, a Tafel slope (−bc) value of 124 mV dec−1 and an exchange current density (jo) of ~0.07 mA cm−2. The FA-TiO2′s HER catalytic performance was significantly enhanced upon cathodic activation (24 h of chronoamperometry measurements performed at a high cathodic potential of −1.0 V vs. RHE). The cathodically activated FA-TiO2 recorded HER electrochemical kinetic parameters of EHER = −28 mV, −bc = 115 mV dec−1, jo = 0.65 mA cm−2, and an overpotential η10 = 125 mV to yield a current density of 10 mA cm−2. Such parameters were comparable to those measured here for the commercial Pt/C under the same experimental conditions (EHER = −10 mV, −bc = 113 mV dec−1, jo = 0.88 mA cm−2, η10 = 110 mV), as well as to the most active electrocatalysts for H2 generation from aqueous alkaline electrolytes.

Comparison of the Properties of Glasses Made from Two Different Bottom Ashes

Bottom ash is a waste byproduct generated from the combustion or incineration of materials such as coal and household waste. It is a mixed oxide powder of variable composition, though typically high in silica. As a low-cost, readily available material, it has found applications primarily in construction for use as backfill. As a silica-rich, mixed oxide powder though, it may also have glass forming ability. This research studied the possibility to use domestically produced bottom ash powder in glass making. Two bottom ash powders were used, one from a waste incinerator (Phuket) and the other from a coal-fired electric plant (Mae Moh Power Plant, Lampang). The bottom ash was milled into a fine powder and melted within the temperature range of 1300-1500 oC, for 2 hours. The melts were cast in a brass mold and then annealed at 500 oC for 2 hours. It was found that both bottom ashes could successfully produce glasses. The Vickers hardness, refractive index and specific gravity of the glasses will be discussed.

A real option analysis on retiring existing coal-fired electricity plants in the United States

A real option analysis on retiring existing coal-fired electricity plants in the United States

Combination Non-Destructive Test (NDT) Method for Early Damage Detection and Condition Assessment of Boiler Tubes

Boilers, the most troublesome components of electric power, chemical and processing plants generate high costs in unscheduled shutdowns, repairs and power replacement. Every occurrence of ruptured tubes leads to emergency shutdown of the entire plant. This paper describes the joint international effort to develop faster and more efficient methods for condition assessment and remaining life prediction for boiler tubes. The work was performed under the grant from Kazakhstan Ministry of Education and Science.The authors have visited a number of coal-fired electric plants throughout Central Asia and found that a combination of wall thinning and overheating were major damage mechanisms contributing to boiler tube failures. The periodic inspection of boiler tubes include ultrasonic measurement of remaining wall thickness and in many cases, it involves cutting tube segments and performing metallurgical analysis for loss of original strength due to overheating. Systematic research was undertaken with the objective to correlate the results of combined non-destructive testing (NDT) with condition assessment of boiler tubes. The evaluation included non-contact wall thickness measurement with EMAT technology plus internal oxide layer measurement with specialized ultrasonics. The first method shows the remaining tube wall thickness, thus allowing to calculate total stress, and the latter one has the potential to indirectly characterize microstructure degradation, which up to now could only be determined by destructive analysis. The existing tube removal criteria are treating each damage mechanism separately while in reality, a combined effect of wall thinning and the “degree of overheating” decides about true condition of a tube. The procedure that utilizes the results of both described NDT methods was developed for improved methodology to assess tube condition and to predict its remaining life.

Wind battles coal for access to China's grid [News

The 16th of October marks the start of heating season in northern China. Traditionally that means firing up coal boilers and pumping excess heat from big coal-fired electric plants to residences and businesses. This year, another heat source will join the mix: wind power. District heating systems across northern China are preparing to use small injections of heat from electric boilers that will be soaking up power generated from the region's robust overnight winter winds.

Cost savings and deregulation: an analysis of fuel cost savings in deregulated electricity markets

ABSTRACTUnregulated utilities face competitive pressures that lead to cost-minimizing activities, but regulated monopolies in the US electricity generation sector face pressures only from regulators who must balance a desire for lower prices against the need for the utility to generate a sufficient return to encourage investment. This paper analyses the cost-minimizing behaviours of regulated utilities by comparing their average input coal costs with those of deregulated utilities purchasing coal from the same mine during the same month of the same year. Results indicate that coal-fired electric plants operating in deregulated electricity markets negotiate prices that are 6.1 ¢/MMBtu (3.5%) less than their regulated counterparts. In percentage terms, this is a fairly small discount for deregulated plants, but it happens to be on par with the restructuring gains that others have estimated for labour and nonfuel costs.

How to address data gaps in life cycle inventories: a case study on estimating CO2 emissions from coal-fired electricity plants on a global scale.

One of the major challenges in life cycle assessment (LCA) is the availability and quality of data used to develop models and to make appropriate recommendations. Approximations and assumptions are often made if appropriate data are not readily available. However, these proxies may introduce uncertainty into the results. A regression model framework may be employed to assess missing data in LCAs of products and processes. In this study, we develop such a regression-based framework to estimate CO2 emission factors associated with coal power plants in the absence of reported data. Our framework hypothesizes that emissions from coal power plants can be explained by plant-specific factors (predictors) that include steam pressure, total capacity, plant age, fuel type, and gross domestic product (GDP) per capita of the resident nations of those plants. Using reported emission data for 444 plants worldwide, plant level CO2 emission factors were fitted to the selected predictors by a multiple linear regression model and a local linear regression model. The validated models were then applied to 764 coal power plants worldwide, for which no reported data were available. Cumulatively, available reported data and our predictions together account for 74% of the total world's coal-fired power generation capacity.

Additional market incentives for abatement: An analysis of flue-gas desulfurization by-products

Energy and environmental regulations often result in by-products that can reduce compliance costs. This research evaluates a unique case in which the marketability of gypsum by-product produced from sulfur dioxide (SO2) scrubbing operations at coal-fired electric plants has a theoretically ambiguous impact on pollution emissions. Intuitively, the ability to market flue-gas desulfurization (FGD) gypsum provides incentives for electricity generating plants to operate their scrubbers more efficiently by providing gypsum revenues, and lowering gypsum disposal costs. Gypsum marketability also creates incentives for plants to burn coal with higher sulfur content in order to increase their gypsum (CaSO4·2H2O) production. The overall impact of FGD gypsum marketability on boiler-level SO2 emissions is therefore the empirical question of interest. Electricity boiler-level fixed-effect estimations suggest annual SO2 emissions decline by 3494tons (39%) as a result of gypsum marketing. An upper bound on the total external benefits associated with the reduced SO2 emissions is estimated at $350.6 billion (2011$), or roughly 2.1% of the total benefits of the U.S. Clean Air Act (CAA) from 1990 to 2010.

Lowering the Energy Cost of Carbon Dioxide Capture using Ejectors for Waste Heat Upgrading

Abstract The largest technical challenge to full-scale post-combustion carbon capture in power plants is the enormous energy consumption for solvent regeneration. If legislative requirements impose CO 2 capture, chemical absorption/desorption using amine solvent solutions is the most mature commercial technology available. The use of ejectors to upgrade external waste heat has recently been shown to significantly reduce the amount of valuable turbine steam required to regenerate the solvent. Using the Aspen Plus chemical process simulator, this study considers three different liquid sources for producing the ejector secondary steam in a waste heat supplied flash tank. In each case the goal is to minimize the sum of the heat duty of the ejector primary steam generator and the stripping tower reboiler. A base case 20 wt% MEA absorption/desorption CO 2 capture process was modeled, with flue gas data from a 400 MW net power coal-fired electric plant. Using stripping column condensate or lean solution to create the ejector secondary steam were found to be viable options for reducing valuable turbine steam consumption, with respective reductions of 14% and 23% shown for the completed simulations. With ejectors, lower temperature waste heat can be used to partially replace valuable turbine steam normally required in the reboiler for solvent regeneration in CO 2 capture.

When a Negative Externality Turns Positive: An Analysis of Flue-Gas Desulfurization By-Products

Energy and environmental regulations often result in the generation of unforeseen marketable by-products that can reduce costs of compliance. This research evaluates a unique case in which the marketability of by-products produces positive external benefits. Specifically, this paper focuses on flue-gas desulfurization (FGD) gypsum by-product produced by coal-fired electric plants using sulfur dioxide (SO2) scrubbing technology to comply with the emission standards set by the 1990 Clean Air Act Amendment (CAAA). Intuitively, the ability to market FGD gypsum provides incentives for electricity generating plants to operate their scrubbers more efficiently by providing gypsum revenues, and lowering gypsum disposal costs. Increased operating efficiency creates external benefits attributed to reduced SO2 emissions that would otherwise not have occurred. In order to estimate the impact of FGD gypsum marketability on SO2 emissions, a unique longitudinal database is constructed that merges electricity plants’ boiler-level SO2 emissions data from the U.S. Environmental Protection Agency (EPA) with data on scrubber operations and coal quality available from the U.S. Energy Information Administration (EIA). Boiler fixed-effect estimations suggest annual SO2 emissions decline by 3,494 tons as a result of gypsum marketing. This corresponds with a 39% average reduction in SO2 emissions at boilers marketing FGD gypsum. The total benefits associated with the reduced SO2 emissions are estimated between $147.1 billion and $350.6 billion (2011$), or between 0.9% and 2.1% of the total benefits of the U.S. CAA from 1990 to 2010.

Association of suicide rates and coal-fired electricity plants by county in North Carolina

Suicide, strongly associated with psychiatric conditions, also correlates with environmental pollution, likely due to quality of life factors which impact mood disorders. This ecological study evaluated the effect of the presence of a coal-fired electricity plant in a county on county suicide rates in North Carolina. Data from the 2000 US Census, 2001-2005 mortality rates from the North Carolina State Center for Health Statistics and the US Environmental Protection Agency were used in multivariable linear regression. Twenty coal plants existed in North Carolina during this study’s period. Only about one third of the population of North Carolina lived in urban areas. Seventy four percent of the population was white, and the mean population per county was nearly 48,000. About 13% of the population lived at or below the poverty level. The median household income of counties was approximately $34,000. County-level suicide rates were higher in North Carolina (12.4/100,000 population) compared to the US population (10.8/100,000). The linear regression model indicated that percent white race, median age of county population and number of coal plants per county explained 25.8% of the variance of county suicide rates. For coal plants, the linear regression model suggests that for each additional coal plant in a given county, there would be an additional 1.96 suicide per 100,000 population. The presence of a coal plant correlated with airborne levels of nickel, mercury, lead, chromium, cadmium, beryllium and arsenic. This is the first study to show that the existence of coal electricity plants is related to population-level suicide rates. Because suicide might be associated with environmental pollution, this study may help inform regulations not only of air pollutants, but also of coal electrical power plant emissions.

Regional Assessment of Woody Biomass Physical Availability as an Energy Feedstock for Combined Combustion in the US Northern Region

Woody biomass is a renewable energy feedstock with the potential to reduce current use of nonrenewable fossil fuels. We estimated the physical availability of woody biomass for cocombustion at coal-fired electricity plants in the 20-state US northern region. First, we estimated the total amount of woody biomass needed to replace total annual coal-based electricity consumption at the state level to provide a representation of the potential energy footprints associated with using woody biomass for electric energy. If all woody biomass available were used for electric generation it could replace no more than 19% of coal-based electric generation or 11% of total electric energy generation. Second, we examined annual woody biomass increment at the state level in a series of concentric circles around existing coal-fired electricity plants to examine some of the opportunities and limitations associated with using woody biomass for cofiring at those plants to coincide with state-level renewable portfolio standards. On average, an individual coal-fired power electricity plant could theoretically replace 10% of annual coal use if it obtained 30% of the net annual woody biomass increment within a 34-km radius of the plant. In reality, the irregular spatial distribution of coal-fired power plants means potential biomass supply zones overlap and would greatly diminish opportunities for cofiring with biomass, numerous other regulatory, economic, and social considerations notwithstanding. Given that woody biomass use for electricity will be limited to selected locations, use of woody biomass for energy should be complementary with other forest conservation goals.

Controlling Mercury Emission for China's Coal Fired Electricity Plants: an Economic Analysis

Abstract This study aims to identify the least-cost strategy for controlling the emission of mercury from coal-fired electricity generation plants in China, which helps to provide technical guidance to firms and decision making basis for designing mercury control strategy and policy for the government. Based on the analysis and evaluation of technical and economic features of the available technologies/alternatives, this study develops a Cost -Effectiveness Oriented Model (CEOM) at enterprises level. A least cost solution for each type of plants is estimated. Further, sector-level mercury abatement cost is estimated by grouping the plants by size and existing technologies, giving concern of the possible policy scenarios which based on proportional allocation of the emission control targets and based on the marginal abatement cost allocation, as well as the existing SO2 control policies. It concludes that by combining the pretreatment technology, particulates removing technology, and SO2 control technology, as well as the NOx control technologies, China can control over 90% of emission. At least 12% of the mercury can be removed by strictly enforcing the Two Control Zone's policy, and the co-benefit is significant by introducing multiple pollutants control. A sets of policy recommendation is concluded, that China should enforce SO2 control policy more effectively, the multiple pollution control strategy should be developed, and a emission trading scheme can provide plant flexibility to compliance and can generate cost saving.

Carbon capture and storage (CCS) demonstration projects in Canada

Abstract Energy sources such as oil, natural gas, and coal currently account for around 80% of the world’s primary energy consumption. Despite significant investments in renewable energy and energy efficiency, that Canada and others are making, the International Energy Agency (IEA) has forecast that as the global economy continues to grow, fossil fuels will continue to dominate the world’s energy supply for decades. Reconciling the world’s ongoing reliance on fossil fuels with the need to reduce greenhouse gas (GHG) emissions is then one of our greatest challenges. Canada is taking this challenge seriously with climate change policies that include enhancing our global leadership in advancing one of the most promising technologies for reducing GHG emissions from fossil fuel use: Carbon capture and storage (CCS). CCS is only one of several technologies that must be deployed and is not a ‘silver-bullet’ for meeting Canada’s target of reducing its GHG emissions by 17% from 2005 levels by 2020. Yet, CCS is one of the only technologies currently available for making emissions reductions from large-scale fossil fuel usage–and, thus, will be a critical component of the technology puzzle for Canada to meet its emissions reduction objectives. Canada has a number of key sectors where the deployment of CCS is needed and there are opportunities to advance the technology. These include coal-fired electricity plants, the oil sands, and natural gas processing (e.g. from the new development of shale gas) -though the opportunity and demand for advancing CCS technology also exists in other sectors such as chemicals, fertilizer, steel making, and cement. Federal and provincial governments in Canada are making substantial investments in CCS, committing upwards of $3 billion in public funding towards seven large-scale fully-integrated CCS demonstration projects. The federal ecoENERGY Technology Initiative announced $151 million for the initial engineering and/or pilot stages of seven potential demonstration projects in 2008. The 2009 federal budget created Clean Energy Fund, which included $610 million for CCS demonstrations. The Provinces of Alberta, Saskatchewan, and British Columbia have also committed funding for demonstrations, in particular $2 billion by Alberta. This public funding will leverage additional investment from industry, for projects that will each capture and store on the order of 1 million tonnes of CO 2 per year, coming on-line starting in 2015 or sooner. This paper will provide an overview of Canada’s actions on advancing CCS deployment, with a focus on the CCS demonstration program and current R&D activities in Canada.

Making concentrated solar power competitive with coal: The costs of a European feed-in tariff

The European Union has yet to determine how exactly to reach its greenhouse gas emissions targets for the future. One potential answer involves large-scale development of concentrated solar power (CSP) in the North African region, transmitting the power to Europe. CSP is a relatively young and little utilized technology and is expensive when compared to other methods of generation. Feasibility studies have shown it is possible to generate enough power from CSP plants in Africa to spearhead the EUs climate goals. However, the costs of such a project are less well known. Currently, CSP must compete with low cost coal-fired electricity plants, severely hindering development. We examine the possible investment costs required for North African CSP levelized electricity cost to equal those of coal-fired plants and the potential subsidy costs needed to encourage growth until the technologies reach price parity. We also examine the sensitivity of investment and subsidies to changes in key factors. We find that estimates of subsidy amounts are reasonable for the EU and that sensitivity to such factors as perceived risk and learning rates would enable policy-makers to positively influence the cost of subsidies and time required for CSP to be competitive with coal.

Tortious liability for greenhouse gas emissions? Climate change, causation and public policy considerations

The purpose of this paper is to assess the potential legal issues in establishing liability for large-scale emitters of greenhouse gases, in Australia, for resulting harms caused from changes to the climate system. This paper assesses the legal principles and policy issues associated with potential negligence claims against industrial emitters in Australia such as large coal mines and coal-fired electricity plants. This paper identifies a range of significant obstacles in successfully bringing claims in negligence for climatic harms. These include issues in foreseeability, causation and the operation of public policy principles. It is concluded that the distribution of risk from climate change, and associated allocation of liability, is more appropriately addressed through consistent, national legislation rather than through the ad hoc adaptation of the common law.

Changes in sulfate deposition in eastern USA following implementation of Phase I of Title IV of the Clean Air Act Amendments of 1990

Phase I of Title IV of the Clean Air Act Amendments of 1990 (CAAA) was implemented on 1 January 1995. On that date limitations were imposed on sulfur dioxide (SO 2) emissions from 110 coal-fired electric utility plants (263 units) in 21 states of which 17 are east of the Mississippi River. Sulfur dioxide emissions at these plants dropped an average 2.86 million tons (38%) from 1995 through 1997, when compared to mean 1993–1994 emissions from these plants. As a result of these reductions, wet sulfate (SO 4 2−) deposition decreased an average of 2.4–4.0 kg ha −1 (10–25%) over a large area of the eastern USA. Based on more than 15 years of data, the decrease in wet deposition was unprecedented in magnitude and spatial extent. The largest decrease occurred across the Mid-Appalachian and Northeast regions of the country, the regions specifically targeted by Phase I for reductions in acidic deposition. Although the reductions in wet SO 4 2−deposition were generally consistent with observed reductions in SO 4 2− concentrations, deviations in precipitation volumes between the pre- and post-Phase I periods did result in some sites recording significantly ( p<0.05) lower post-Phase I concentrations but higher wet depositions. Deviations in precipitation within and between regions also influenced the magnitude and spatial distribution of the observed changes in wet SO 4 2− deposition. Clearly, deviations in the amount and distribution of precipitation need to be considered along with concentration changes in evaluating the CAAA effectiveness in reducing acidic deposition. This is particularly important in the eastern USA, since many of the most acid-sensitive ecosystems are located in regions, mostly mountainous and forested, that are subject to considerable fluctuations in precipitation volumes and subsequently acidic wet deposition.

Haze obscuring Grand Canyon to be reduced

The thick haze that sometimes over the Grand Canyon and ruins views of this natural wonder will be considerably reduced under an agreement reached between the largest electric power plant nearby and a regional conservation organization. The proposed cleanup has the backing of the Environmental Protection Agency. The Grand Canyon Trust, a conservation group, and the Salt River Project, an Arizona public utility and operator of the huge Navajo Generating Station, have been arguing for years over how much the 2250-MW coal-fired electric plant was contributing to the canyon's haze. Studies by EPA in the late 1980s and by the public utility itself in 1990, however, confirmed that 40 to 60% of the sulfur dioxide in the particulates over the canyon during the worst haze episodes came from the power plant. Grand Canyon Trust president Edward Norton says the agreement sets a new standard for corporate responsibility and public service/7 He also notes this ...