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The recent trend of increasing share of renewable energy sources (RES) in the generation mix has necessitated new operational and planning studies because of the high degree of uncertainty and variability of these sources. RES such as solar photovoltaic and wind generation are not dispatchable, and when there is excess energy supply during off-peak hours, RES curtailment is required to maintain the demand-supply balance. Furthermore, RES are intermittent resources which have introduced new challenges to the provision of ancillary services that are critical to maintaining the operational reliability of power systems. Energy storage systems (ESS) play a pivotal role in facilitating the integration of RES to mitigate the aforementioned issues. Therefore, there is a growing interest in recent years to examine the potential of ESS in the future electricity grids. This research focuses on developing market participation and investment planning frameworks for ESS considering different ownership structures. First, a novel stochastic planning framework is proposed to determine the optimal battery energy storage system (BESS) capacity and year of installation in an isolated microgrid using a novel representation of the BESS energy diagram. A decomposition-based approach is proposed to solve the problem of stochastic planning of BESS under uncertainty. The optimal decisions minimize the net present value of total expected costs over a multi-year horizon considering optimal BESS operation using a novel matrix representing BESS energy capacity degradation. The proposed approach is solved in two stages as mixed integer linear programming (MILP) problems; the optimal ratings of the BESS are determined in the first stage, while the optimal installation year is determined in the second stage. Extensive studies considering four types of BESS technologies for deterministic, Monte Carlo Simulations, and stochastic cases are presented to demonstrate the effectiveness of the proposed approach. The thesis further studies the ...

Introduction: Wind turbines are a source of renewable energy that has become more common in Canada in the past decades. Concerns have been raised over potential adverse health effects from exposure to wind turbines, particularly wind turbine noise. A disagreement exists over the potential harm from exposure to wind turbines to human health, where many public health organizations state that there are no direct human health impacts from wind turbine exposure, while many community groups state that wind turbines are harmful to human health. Objectives: 1. Determine the types of evidence cited by community group websites, and by public health organization websites, to support their respective positions on the potential health effects of wind turbines; and 2. Assess the pattern of citations or links to the evidence used by community groups and public health organizations to characterize and interpret these patterns of evidence citation and to see whether and how these patterns differ between the two groups. Methods: Websites of Canadian community groups, public health organizations, environmental non-governmental organizations (eNGOs) and academic organizations were identified using an Internet search strategy. The identified websites with content on wind turbines and human health that met the inclusion criteria were characterised with a data collection tool to gather information about the webpage structure and its links to evidence sources and other organizations’ websites. Descriptive statistical analysis was performed on the website characteristics and evidence and organization citation data. Testing for significant differences between community groups and public health organizations was done using t-tests and chi-squared tests. Adjacency matrices were created to represent the presence of ties between organization websites and between organization websites and evidence sources. Graphs (sociograms) were created based on the adjacency matrices to visualise the relationship between the different types of ...

采用共沉淀法合成磁性Fe_3O_4,通过碳化磺化制备核壳结构的磁性固体酸催化剂Fe_3O_4/C-SO_3H,并利用透射电子显微镜(TEM)、傅里叶变换红外光谱仪(FT-IR)、X射线衍射(XRD)、振动样品磁强计(VSM)、元素分析等手段对催化剂特性进行表征分析。以催化玉米芯水解所得的木糖得率为评价指标,对磁性固体酸催化剂催化玉米芯水解工艺条件进行优化研究,得出最佳条件为反应时间10 h、反应温度140 ℃、催化剂用量1.5 g、固液比(g/mL)2∶50(玉米芯含量为0.5 g),此时木糖得率为51.01%。研究认为,磁性固体酸催化剂催化木质纤维素水解的反应过程为酸催化和吸附过程共同作用,木质纤维素是分级解聚逐步转化,利用两步操作能够最大程度的水解木质纤维素。

Growing interest in improving the energy consumption efficiency in residential and commercial buildings has led to the emergence of intelligent energy management systems. This growing technology allows the transformation of the outdated electric distribution network within buildings to a smart and intelligent system. A major challenge in the development of such infrastructure is the need for low cost, integrated, self-contained, and non-invasive wireless sensor nodes. While an electric meter provides the utility company with information regarding the total energy consumption, no information is provided to the consumers regarding the energy consumed by individual appliances. Such visibility can provide consumers with the ability to better control and manage their energy usage leading to a reduced overall energy consumption. This work explores the design and development of a self-contained and non-invasive integrated system intended for real-time electricity monitoring within residential and commercial buildings. The proposed system includes an Energy Harvester, an electric current sensor, a Micro-controller Unit, and a wireless communication device. The proposed system is self-powered and non-invasive, which offers a promising solution in providing real time information regarding the energy distribution within buildings. The design featured in this work provides an innovative approach in the development of a customized interface circuitry that is designed to collect and regulate the energy from the Energy Harvester. The entire sensor node will operate under a power budget in the range of microwatts collected by the Energy Harvester. A Wireless MCU is programmed to acquire, process, and transmit the data from the sensor to the central hub via Bluetooth Low Energy connectivity. The real-time data transmitted to the central hub provides detailed information regarding the energy consumed by individual appliances within the building.

Climate change is undeniably one of humanity’s utmost concerns. Human actions, such as deforestation, exhaustive use of fossil fuels, and intensive farming, are changing weather patterns, threatening polar bears, and causing other detrimental environmental changes. Most people are aware of these effects, yet many are not engaging in behaviour to alleviate the impacts of climate change. This project examined through a literature review and data analysis to determine the extent to which instructional strategies could change these types of behaviours. This quantitative study analyzed 2006 PISA (Program for International Student Assessment) data to determine if the pedagogy utilized by climate change teachers in Kyrgyzstan, Turkey, and Qatar impacted students’ willingness to engage in climate-change mitigating behaviour. These countries were selected because they are Muslim cultures of varied histories with different political and social situations. Thus, this study was additionally interested in discovering how the pedagogical approaches of teachers differed in their impact on students’ willingness to engage in climate-change mitigating behaviour among these three Muslim countries. Factor and reliability analyses were conducted in addition to a regression analysis, which indicated a small but significant relationship between instructional approaches and behaviour to lessen climate change. Instructional approach accounted for 4.0 percent of the climate change mitigating variable for Kyrgyzstan, 2.1 percent for Turkey, and 2.3 percent for Qatar. Future research could focus on the development of a questionnaire to better establish the range of factors that could lead to students more often engaging in behaviour to alleviate the effects of climate change.

Synthetic dispersants are commonly used in the stabilization of various colloidal suspensions. However, their non-biodegradable and toxic natures hamper their industrial use. The use of natural polymers as dispersants for various colloidal suspensions has been reported in the past, but the incentive for producing highly efficient natural polymeric dispersants is high. Lignin and xylan are the most abundant and sustainable natural polymers on earth, which are produced as by-products of pulping and cellulosic ethanol industries. These chemicals can be considered as the raw materials for producing value added products such as dispersants. In this dissertation, the anionic modification of kraft lignin and xylan via carboxymethylation, sulfomethylation and oxidation were comprehensively investigated and the applications of the products as dispersants in kaolin and coal suspensions were systematically assessed. The influence of reaction conditions on charge density and solubility of kraft lignin or xylan were systematically investigated. The anionic products obtained were characterized using NMR, FTIR, TGA, molecular weight and elemental analyses. The adsorption of anionic lignin or xylan on kaolin and coal particles and their effect on zeta potential of the suspensions was comprehensively assessed. The relative turbidity and viscosity analyses of colloidal suspensions confirmed the better dispersion performance of the products compared with commercial ones. The impact of dispersant dosage, pH of the suspension and time of mixing on dispersant performance of anionic lignin or xylan in kaolin and coal suspensions was also studied. The dispersion efficiency of suspensions found to increase with anionic lignin or xylan dosage and time of mixing. The dispersion efficiency of anionic lignin or xylan was at maximum under neutral conditions. The influences of molecular weight and charge density on the dispersant performance of anionic lignin in kaolin suspensions were also studied. The results showed that a highly charged ...

The uptake of energy-efficiency investments in the residential sector is relatively low, despite evidence of short payback periods and numerous co-benefits, including increased home comfort and reduced negative environmental impacts. Common barriers facing homeowners include financial and time constraints, competing priorities, and a lack of adequate information. Home energy audits are an established approach to encourage energy-efficiency investments, with the intention of overcoming the informational barrier by providing personalized energy-efficiency recommendations to homeowners. However, literature suggests that the impacts of these audits are mixed, due to a lack of guidance, procedural information and support from social networks. To fill this gap, the Home Energy Coach program was piloted in Waterloo Region, Ontario, involving government, non-profit, industry and academic stakeholders. Upon receiving an EnerGuide home energy evaluation, homeowners were eligible to participate in free consultation sessions with an Energy Coach to help develop and execute a renovation plan. This thesis documented the coach interactions and renovation progress of 21 program participants through a series of online surveys, with added insight from follow-up interviews with five of these participants. The results indicated that the Energy Coach was helpful in the development of renovation plans of many participants by clarifying the audit recommendations, helping to evaluate options based on each household’s circumstances and guiding participants to additional resources. At the end of the program, 17 out of 18 exit survey respondents had made progress on or completed at least one-energy efficiency measure, with an overall conversion rate of 29 percent from audit recommendation to completed action. The most frequently completed measures were basement/crawl space insulation, draftproofing and window/door replacement, which were also the most frequently recommended measures. This thesis adds to the literature on motivations and ...

Oligotrophic catchments with short spatey streams, upland lakes and peaty soils characterise northwest European Atlantic coastal regions. These catchments are important biodiversity refuges, particularly for sensitive diadromous fish populations but are subject to changes in land use and land management practices associated with afforestation, agriculture and rural development. Quantification of the degree of catchment degradation resulting from such anthropogenic impacts is often limited by a lack of long-term baseline data in what are generally relatively isolated, poorly studied catchments. This research uses a combination of palaeolimnological (radiometrically-dated variations in sedimentary geochemical elements, pollen, diatoms and remains of cladocera), census, and instrumental data, along with hindcast estimates to quantify environmental changes and their aquatic impacts since the late 19th century. The most likely drivers of any change are also identified. Results confirm an aquatic biotic response (phyto- and zooplankton) to soil erosion and nutrient enrichment associated with the onset of commercial conifer afforestation, effects that were subsequently enhanced as a result of increased overgrazing in the catchment and, possibly, climate warming. The implications for the health of aquatic resources in the catchment are discussed Environmental Protection Agency in Ireland (ILLUMINATE 2005-W-MS-40, P.McGinnity was supported by the Beaufort Marine Research Award in Fish Population Genetics funded by the Irish Government under the Sea Change Programme.

Climate change has become one of the most urgent challenges facing our planet today. The consequences we are gradually experiencing have been driven by human activity. Specifically, the increase in energy demand, met mainly through the combustion of fossil fuels such as coal, oil derivatives and natural gas, has significantly increased greenhouse gas emissions, especially carbon dioxide (CO2), leading to global warming. To address the environmental problems arising from climate change, which we are gradually experiencing, it is clear that the development of the use of renewable energy sources is the key to the transition from fossil fuels to these innovative energy alternatives, in order to achieve zero emissions and contribute to decarbonization. However, the deployment of these clean energies requires the development of systems that guarantee continuous energy production, to overcome interruptions caused by the variability of natural resources like wind, sun, or water. A viable solution to this issue is employing energy storage technologies to correct the mismatch between energy supply and demand. In particular, in the specific case of the use of the sun as a renewable thermal energy source, thermal energy storage (TES) systems are of great interest, since more than half of the energy demanded in industry is thermal energy. Among the different sensible TES media, conventional concrete is emerging as a very attractive option for use as TES due to its low cost, high availability, ease of processing, high specific heat, good mechanical stability at high temperature and excellent operational performance when subjected to thermal cycling. And despite its moderate thermal conductivity, research has shown that incorporating multiple heat exchangers through which the heat transfer fluid (HTF) passes in concrete improves its efficiency, albeit at an increased cost. However, caution should be exercised in the use of concrete as the production of its precursor, Portland cement (PC), is a significant contributor to greenhouse gas emissions, particularly CO2. It is estimated that for every ton of PC produced, approximately one ton of CO2 is released into the atmosphere. For this reason, construction materials must be rethought and one of the lines of research to reduce CO2 emissions is the search for alternative precursors known as supplementary cementitious materials (SCM). SCMs enable the full or partial substitution of PC. Complete replacement of PC leads to the development of alkali-activated materials (AAM), while partial replacements, typically around 70-80%, result in the development of hybrid materials (HM). This Doctoral Thesis involves the fabrication of both alternative cementitious materials, AAM mortars and HM mortars, to investigate their feasibility as TES. Specifically, for both alternatives, the main precursor used as a substitute is blast furnace slag (BFS), an industrial by-product that has proven to be a promising alternative. In the case of the AAM mortar composed of BFS, SLAG, the activation of the precursor is carried out with sodium silicate due to the excellent mechanical properties of the final cementitious material. Nevertheless, the use of solutions makes the workability of these systems difficult, so HM with BFS (HSLAG) are also manufactured, which hydrate in the presence of water. HM mortars are composed of almost 80% BFS, about 20% PC and 5% sodium sulphate to promote the alkaline medium necessary for BFS activation. After verifying through a life cycle analysis (LCA) that alternative mortars offer benefits in terms of carbon footprint and water footprint, as well as continuing to manufacture alternatives focused on PC substitution, the possibility of replacing the natural aggregate with glass waste (GW) is investigated. The substitution of sand is carried out in the three types of mortars (AAM, HM and reference PC) with the aim of reducing water consumption, as sand is the component with the highest water demand. However, only the AAM system, SLAG, allows up to 25% of sand to be replaced by GW (SLAG75), thanks to the high cohesion of its main reaction product, the C-A-S-H gel. When the alternatives are manufactured together with the PC reference mortar, both the compressive mechanical properties and the key thermal properties for a TES, thermal conductivity and specific heat, are evaluated before and after various thermal treatments. After analyzing how the mechanical and thermal properties are affected after thermal treatments −including exposure to constant temperatures and thermal cycling−, it is determined that the alternative systems offer comparable and even superior mechanical stability under temperature exposure than a conventional PC system. In addition, alternative materials, characterized by their thermal conductivity and specific heat, show a superior suitability for TES applications compared to PC. More specifically, the AAM system, SLAG, exhibits operational characteristics superior to PC by reducing heat-up times and increasing its storage capacity, which allows for a reduction in TES volume and a reduction in heat exchanger surface area. While the HM system, HSLAG, does not reach the performance of SLAG, it does offer operational improvements compared to PC. These promising results are attributed to less degradation of the reaction products generated in the alternative mortars and better cohesion between the binder and the aggregate. This last factor had a negative effect on SLAG75, as the weakness in the bond created between the binder and the GW, as well as a greater difference in the coefficients of thermal expansion (CTE), lead to the generation of porosity, and even cracks, which determine both the mechanical and thermal behavior. Thus, when selecting a material such as TES, porosity must be controlled and evaluated as a critical parameter. The results displayed by the PC alternative systems developed in this Doctoral Thesis demonstrate their suitability to be selected as sustainable TES both at low-medium and high temperatures. Consequently, it can be generally concluded that the proposed alternative materials show a promising potential for their application as TES blocks. Thus, further research and development in this field could lead to the widespread adoption of these materials as TES, thus contributing to the transition towards sustainable and renewable energy systems.