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This repository contains the raw data of the inputs and results presented in the paper "Electrification of light-duty vehicle fleet alone will not meet mitigation targets" published in Nature Climate Change (2020) by Alexandre Milovanoff, I. Daniel Posen, and Heather L. MacLean (Department of Civil & Mineral Engineering, University of Toronto).

Promotion of agroforestry practices in sub-Sahara Africa may help sustain subsistent food and wood production by integrating trees and crops on farmlands to replenish soil fertility and improve crop yield. Using rotational woodlot and pigeonpea intercropping systems in semi-arid Tanzania as case studies, my research screened suitable tree species to increase fuelwood supply and examined mechanisms for reducing tree-crop competition. By adopting nutrient use efficiency (the ratio of biomass yield to nutrient uptake) as a criterion, I found that selecting tree species of low wood nutrient concentrations would minimize nutrient exports by 42 – 60 %, thus reducing soil nutrient depletion while concurrently sustaining local fuelwood supply harvested from rotational woodlots. Currently smallholder farmers cannot afford to replenish soil fertility because of high fertilizer costs. However, 5-year tree fallowing raised soil N and P levels for maize culture as high as those from recommended fertilizer applications. Post-fallow maize yield was also increased significantly over natural fallow practices. Apparently there is a trade-off between yields of maize and fuelwood under rotational woodlot culture providing farmers the choice to proportion tree and crop composition based on priority demands. An alternative practice of intercropping pigeonpea with maize may also rapidly replenish soil fertility as well as enhance maize yield when competitive interactions between trees and crops are controlled. Vector analysis revealed that such interactions suppressed biomass yields of maize and pigeonpea by 30 % and 60 %, respectively, due to limited soil nutrients and/or moisture. Optimizing yields of both crops would require prescribed fertilizer addition when intercropped, but dose rates can be lowered by half under the improved fallow system due to alleviating interspecific competition. My findings form the basis of a plea for greater use of rotational woodlot and pigeonpea intercropping systems in semi-arid areas. I conclude that smallholder farm management of rotational agroforestry systems can be significantly improved by refining tree selection criteria and mitigating nutrient competition between trees and crops to maintain food and fuelwood production. ; PhD

Accurate prediction of tube surface temperature is important for determining whether accelerated superheater corrosion will occur in kraft recovery boilers. A heat transfer model, which combines an iterative numerical solution scheme with a more realistic flue-gas flow field obtained from a CFD code FLUENT, has been developed to predict the tube, steam, and flue-gas temperatures in the superheater region. Results of tests performed for a recovery boiler show that temperatures predicted by the model are in good agreement with actual temperatures measured using thermocouples. The presence of a large flue-gas recirculation zone above the bullnose is shown to have an adverse effect on the heat transfer in the superheater region. ; This work is part of the research on “Recovery Boiler Fireside Deposits,” supported by ABB Combustion Systems, Ahlstrom Corp., Aracruz Cellulose SA, Babcock & Wilcox Co., Champion International Corp., Diamond Power Specialty Co., E. B. Eddy Forest Products Ltd., Gotaverken Energy Systems, Jansen Combustion and Boiler Technologies Inc., James River Corp., Tampella Power Corp., Union Camp Corp., Westvaco Corp., Weyerhaeuser Co., Willamette Industries, and the Ontario Ministry of Colleges and Universities through its URIF program.

Boronsubphthalocyanines (BsubPcs) are a class of organic semiconducting materials which are relatively underdeveloped in their synthetic methods and organic semiconducting applications. A comprehensive investigation of these materials is explored in a rigorous and strategic manner progressing through each stage of the materials development cycle: materials selection from computational screening, organic/organometallic synthesis of target materials using known methods or by the development of new synthetic methods, physical and chemical analysis of new materials, and device implementation in organic light emitting diodes and organic photovoltaic cells. The result is the formation of new compositions of BsubPc specifically engineered for application as organic semiconductors in devices. Specifically, phenoxy-boronsubphthalocyanine derivatives are investigated starting with a computational study of their molecular orbitals – a property that dictates their function (donor or acceptor behaviour) in organic electronic devices. The nature of the axial phenoxylate is found to vary the energy level of the frontier molecular orbitals minimally, by up to ~0.4 eV while the nature of the BsubPc periphery can shift the energy levels of the frontier molecular orbitals by >1 eV. The differential sensitivity of the axial phenoxylate and the BsubPc periphery becomes a key design element allowing controlled adjustments of the frontier molecular orbitals by peripheral modification and isolating the design physical chemical properties essential to device fabrication to the axial phenoxylate. Subsequently, an investigation into the solubility and sublimability of these materials is performed, which leads to their investigation in OLED and OPV devices. The success from the phenoxy-BsubPcs study has led to the exploration of new chemistry to expand the available axial nucleophiles beyond phenoxylates. Previously unattainable sulphur and nitrogen nucleophiles are synthesised using two methods (1) the condensation of Cl-BsubPc with phthalimides and (2) the activation of Cl-BsubPc using aluminum chloride to access thiols and anilines. The phthalimido-BsubPcs synthesized from this method are incorporated in OLEDs. ; PhD

This thesis investigates the computation of invariance kernels for planar nonlinear systems with one input, with application to wind turbine stability. Given a known bound on the absolute value of the input variations (possibly around a fixed non-zero value), it is of interest to determine if the system's state can be guaranteed to stay within a desired region K of the state space irrespective of the input variations. The collection of all initial conditions for which trajectories will never exit K irrespective of input variations is called the invariance kernel. This thesis develops theory to characterize the boundary of the invariance kernel and develops an algorithm to compute the exact boundary of the invariance kernel. The algorithm is applied to two simplified wind turbine systems that tap kinetic energy of the turbine to support the frequency of the grid. One system provides power smoothing, and the other provides inertial response. For these models, limits on speed and torque specify a desired region of operation K in the state space, while the wind is represented as a bounded input. The theory developed in the thesis makes it possible to define a measure called the wind disturbance margin. This measure quantifies the largest range of wind variations under which the specified type of grid support may be provided. The wind disturbance margin quantifies how the exploitation of kinetic energy reduces a turbine's tolerance to wind disturbances. The improvement in power smoothing and inertial response made available by the increased speed range of a full converter-interfaced turbine is quantified as an example. ; PhD

The original goal of this thesis was to develop process chemistry to yield boron subphthalocyanine (BsubPc) derivatives which were previously difficult to access. Retrospectively, it was found that these compounds show extremely high density crystal packing in comparison to other known BsubPcs, and thus this also became a focus of the thesis. A process to synthesize and purify fluoro-BsubPc was developed. This led to a detailed comparison of the physical and chemical properties of the three halo-BsubPcs in order to answer the question of which halo-BsubPc is appropriate for different purposes. Through this work, the previously unpublished crystal structure of the oxygen bridged dimer, µ-oxo-BsubPc, was found. A process was subsequently developed for the practical synthesis of µ-oxo-BsubPc for use in vacuum deposition and a number of µ-oxo-BsubPc crystal polymorphs were found and analyzed. The properties of this group of compounds are discussed in the context of other known BsubPcs. ; MAST

Three different green technologies are compared in terms of net energy and carbon savings for a theoretical Toronto rooftop. Embodied energy values are calculated through Life Cycle Analysis and compared to the estimated energies produced and/or saved by each technology. Results show that solar photovoltaics displace the most carbon per m2 of roof space and solar thermal (for hot water) displaces the most energy. An in-depth analysis of an intensive green roof for growing food indicates that the high embodied energy of the materials is not quickly repaid by the sum of six energy savings that were examined (direct and indirect cooling, run-off treatment, transport of food, on-farm energy use, and activities that would otherwise be carried out). However, the energy and carbon benefits are not insignificant, but depend strongly on various assumptions. The methodology used is replicable and therefore useful for other locations. ; MAST

British Columbia’s energy policy is at a crossroads; the province has set a goal of electricity self-sufficiency, a 93% renewable portfolio standard and provincial natural gas strategy that could increase electricity consumption by 2,500-3,800 MW. To ascertain the reality of BC’s supply position, we model the physical characteristics of BC’s hydroelectric generating system introducing variable head heights for the two dominant power stations. Using historical inflow and reservoir level data, we apply our linear programming model to investigate whether BC is capable of meeting is self-sufficiency goals under various supply and demand scenarios.

The well-to-wheel (WTW) environmental performance of plug-in hybrid electric vehicles (PHEVs) is sensitive to driving patterns, which vary within and across regions. This thesis develops and applies a novel approach for estimating specific regional driving patterns. The approach employs a macroscopic traffic assignment model linked with a vehicle motion model to construct driving cycles, which is done for a wide range of driving patterns. For each driving cycle, the tank-to-wheel energy use of two PHEVs and comparable non-plug-in alternatives is estimated. These estimates are then employed within a WTW analysis to investigate implications of driving patterns on the energy use and greenhouse gas emission of PHEVs, and the WTW performance of PHEVs relative to non-plug-in alternatives for various electricity generation scenarios. The results of the WTW analysis demonstrate that driving patterns and the electricity generation supply interact to substantially impact the WTW performance of PHEVs. ; MAST

This thesis introduces a new photovoltaic (PV) system architecture employing low voltage parallel-connected PV panels interfaced to a high voltage regulated DC bus of a three-phase grid-tied inverter. The concept provides several improvements over existing technologies in terms of cost, safety, reliability, and modularity. A novel resonant mode DC-DC boost converter topology is proposed to enable the PV modules to deliver power to the fixed DC bus. The topology offers high step-up capabilities and a nearly constant efficiency over a wide operating range. A reduced sensor maximum power point tracking (MPPT) controller is developed for the converter to maximize energy harvesting of the PV panels. The reduced sensor algorithm can be generally applied to the class of converters employing pulse frequency modulation control. A ZigBee wireless communication system is implemented to provide advanced control, monitoring and protection features. A testbench for a low cost 500 $W$ smart microconverter is designed and implemented, demonstrating the viability of the system architecture. ; MAST