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Investigation of sustainable energy alternatives for powering remote communities in northern Ontario
ABSTRACT Remote communities in the North of Ontario survive in isolation as their proximity to the southern industrial sector of the province limits their accessibility to the major grid. The lack of grid connection has led to antiquated methods of power generation which pollute the environment and deplete the planet of its natural resources. Aside from the primary means of electricity generation being by diesel generators, generation infrastructure is deteriorating due to age and the stagnation of the power supply has led to communities facing load restrictions. These challenges may be resolved by introducing clean energy alternatives and providing a fuel blend option. The primary energy sources investigated in this research are solar, wind, and hydrogen. To assess the viability of these energy production methods in Northern communities, an exergy analysis is employed as it utilizes both the first and second law of thermodynamics to determine systems’ efficiency and performance in the surroundings. Local weather patterns were used to determine the viability of using wind turbines, solar panels and/or hydrogen fuel cells in a remote community. Through analysis of the resources available at the community, it was determined that the hydrogen fuel cell was best suited to provide clean energy to the community. Wind resulted in low efficiency in the range of 2–3% while solar efficiencies resulted in ranges of 18 – 19%, as the seasonal variations between the three years is not very great. Due to the higher operating efficiencies observed of the PV panels it would also be an attractive alternative to diesel generators however, the lack of consistent operation above 30% efficiency throughout the year, resulted in hydrogen fuel cells being a better alternative. 相似文献
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Morton-Bermea Ofelia Beramendi-Orosco Laura Martínez-Reyes Ángeles Hernández-Álvarez Elizabeth González-Hernández Galia 《Environmental geochemistry and health》2016,38(1):195-202
Environmental Geochemistry and Health - Tree rings may be used as indicators of contamination events providing information on the chronology and the elemental composition of the contamination. In... 相似文献
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Ofelia Morton-Bermea Omar Amador-Muñoz Lida Martínez-Trejo Elizabeth Hernández-Álvarez Laura Beramendi-Orosco María Elena García-Arreola 《Environmental geochemistry and health》2014,36(5):987-994
The increase in platinum (Pt) in the airborne particulate matter with size ≤2.5 µm (PM2.5) in urban environments may be interpreted as result of the abrasion and deterioration of automobile catalyst. Nowadays, about four million vehicles in Mexico City use catalytic converters, which means that their impact should be considered. In order to evaluate the contribution of Pt to environmental pollution of the metropolitan area of Mexico City (MAMC), airborne PM2.5 was collected at five different sites in the urban area (NW, NE, C, SW, SE) in 2011 during April (dry-warm season), August (rainy season) and December (dry-cold season). Analytical determinations were carried out using a ICP-MS with a collision cell and kinetic energy discrimination. The analytical and instrument performance was evaluated with standard road dust reference material (BCR-723). Median Pt concentration in the analyzed particulate was is 38.4 pg m?3 (minimal value 1 pg m?3 maximal value 79 pg m?3). Obtained Pt concentrations are higher than those reported for other urban areas. Spatial variation shows that SW had Pt concentration significantly higher than NW and C only. Seasonal variation shows that Pt median was higher in rainy season than in both dry seasons. A comparison of these results with previously reported data of PM10 from 1991 and 2003 in the same studied area shows a worrying increase in the concentration of Pt in the air environment of MAMC. 相似文献
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Nasrin Mostafavi Pak Ofelia Rempillo Ann-Lise Norman 《Journal of the Air & Waste Management Association (1995)》2016,66(8):739-747
The early atmospheric detection of carbon dioxide (CO2) leaks from carbon capture and storage (CCS) sites is important both to inform remediation efforts and to build and maintain public support for CCS in mitigating greenhouse gas emissions. A gas analysis system was developed to assess the origin of plumes of air enriched in CO2, as to whether CO2 is from a CCS site or from the oxidation of carbon compounds. The system measured CO2 and O2 concentrations for different plume samples relative to background air and calculated the gas differential concentration ratio (GDCR = ?ΔO2/ΔCO2). The experimental results were in good agreement with theoretical calculations that placed GDCR values for a CO2 leak at 0.21, compared with GDCR values of 1–1.8 for the combustion of carbon compounds. Although some combustion plume samples deviated in GDCR from theoretical, the very low GDCR values associated with plumes from CO2 leaks provided confidence that this technology holds promise in providing a tool for the early detection of CO2 leaks from CCS sites. Implications: This work contributes to the development of a cost-effective technology for the early detection of leaks from sites where CO2 has been injected into the subsurface to enhance oil recovery or to permanently store the gas as a strategy for mitigating climate change. Such technology will be important in building public confidence regarding the safety and security of carbon capture and storage sites. 相似文献
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Delgado-Alvarez Carolina Guadalupe Ruelas-Inzunza Jorge Osuna-Martínez Carmen Cristina Bergés-Tiznado Magdalena Elizabeth Escobar-Sánchez Ofelia Ocampo-Rodríguez Pedro Octavio Soto-Romero Karen Lizbeth Garzón-Raygoza Nancy Lorena Aguilar-Júarez Marisela Osuna-López José Isidro Frías-Espericueta Martín 《Environmental science and pollution research international》2021,28(9):10909-10917
Environmental Science and Pollution Research - Mercury and selenium concentrations and Se:Hg molar ratio in edible muscle and hepatopancreas of the crab Callinectes arcuatus from coastal lagoons of... 相似文献
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Seeds of promise: Developing a sustainable agricultural biotechnology industry in sub–Saharan Africa
Paul Keese Ofelia Galman–Omitogun & E. Babafunso Sonaiya 《Natural resources forum》2002,26(3):234-244
In a continent ravaged by poverty, disease and malnutrition, agricultural practices have changed little over millennia. Of all the new technologies recently arisen, molecular biotechnology is one of the few that could signi ficantly improve the livelihoods of the large numbers of people in sub–Saharan Africa. Its impact could exceed that in the developed world, where a multi–billion dollar a year agricultural biotechnology industry has emerged, secured on the back of a highly skilled research and educational sector, extensive biosafety measures, and a strong corporate sector. For much of sub–Saharan Africa, the absence of these foundations constitutes a substantial hurdle to the development of a sustainable biotechnology industry. A critical element is the development of an indigenous and innovative agricultural biotechnology community — one that is responsive to African crops, farming practices and economic imperatives, yet sensitive to local concerns and biosafety issues surrounding use of the controversial GM technology. 相似文献
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Martínez-Pérez Mariana Arenas-Huertero Francisco Cortés-Eslava Josefina Morton-Bermea Ofelia Gómez-Arroyo Sandra 《Environmental science and pollution research international》2021,28(24):31032-31042
Environmental Science and Pollution Research - Evaluate the effect of heavy metals (HM) on sentinel organisms such as vascular plants represent a model to estimate toxic hazard due to environmental... 相似文献
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Bercaru O Gawlik BM Ulberth F Vandecasteele C 《Journal of environmental monitoring : JEM》2003,5(4):697-705
During recent years, the awareness of quality assurance and quality control in environmental analyses has constantly increased, especially due to the implementation of new guidelines and regulations at both the national and international level. Achieving comparable results by using certified reference materials is one of the primary concerns of the scientific community. As a result, there is a growing demand for certified reference materials to cover different matrices and pollutants. Moreover, these CRMs should be in close relationship to the determinants and target concentrations required by environmental bodies and European Directives as well. Supplementary information to this paper presents an inventory of reference materials available on the market from different suppliers against the priority pollutants listed in the Water Framework Directive. These CRMs cover matrices such as water, sediment and biota. The use of CRMs in relationship to appropriate analytical methods and relevant determinants is discussed and the need for matrix-CRMs, particularly for organic pollutants is emphasised. The use of proficiency testing schemes as an alternative for the lack of appropriate CRMs and future trends in the production of CRMs within the BCR framework are also discussed. 相似文献
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Ofelia Gonzalez Andreas Zedrosser Fanie Pelletier Jon E. Swenson Marco Festa-Bianchet 《Behavioral ecology and sociobiology》2012,66(7):1025-1032
Experimental manipulations have revealed positive effects of litter reduction on offspring mass in small mammals, but little is known about this trade-off in large mammals. We examined the determinants of natural litter size variation and quantified the effects of litter size, maternal characteristics, and litter composition on yearling mass using 24?years of data on marked brown bears (Ursus arctos) in Sweden. Infanticide by adult males is a major cause of cub-of-the-year mortality, leading to litter size reductions. Litter size (n?=?265) at den emergence ranged from one to four cubs (average, 2.7) and increased with maternal age. Litter size, however, appeared independent of maternal size, population density, interlitter interval, study area, or previous litter sex ratio. Yearling body mass increased with maternal body size but was independent of litter sex ratio. Litter size and yearling mass were negatively correlated, mostly because singletons were about 30?% heavier than yearlings from litters of two to four cubs. In reduced litters, survivors were on average 8?% heavier as yearlings than individuals from intact litters, suggesting that sibling competition reduces growth. Trade-offs between litter size and yearling mass in bears appear similar in magnitude to those found in small mammals. 相似文献
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