The Economic Case for Electric Mining Equipment and Technical Considerations Relating to their Implementation

Underground hardrock mining can be very energy intensive and in large part this can be attributed to the power consumption of underground ventilation systems. In general, the power consumed by a mine’s ventilation system and its overall scale are closely related to the amount of diesel power in operation. This is because diesel exhaust is a major source of underground air pollution, including diesel particulate matter (DPM), NO2 and heat, and because regulations tie air volumes to diesel engines. Furthermore, assuming the size of airways remains constant, the power consumption of the main system increases exponentially with the volume of air supplied to the mine. Therefore large diesel fleets lead to increased energy consumption and can also necessitate large capital expenditures on ventilation infrastructure in order to manage power requirements. Meeting ventilation requirements for equipment in a heading can result in a similar scenario with the biggest pieces leading to higher energy consumption and potentially necessitating larger ventilation tubing and taller drifts. Depending on the climate where the mine is located, large volumes of air can have a third impact on ventilation costs if heating or cooling the air is necessary. Annual heating and cooling costs, as well as the cost of the associated infrastructure, are directly related to the volume of air sent underground. This thesis considers electric mining equipment as a means for reducing the intensity and cost of energy consumption at underground, hardrock mines. Potentially, electric equipment could greatly reduce the volume of air needed to ventilate an entire mine as well as individual headings because they do not emit many of the contaminants found in diesel exhaust and because regulations do not connect air volumes to electric motors. Because of the exponential relationship between power consumption and air volumes, this could greatly reduce the amount of power required for mine ventilation as well as the capital cost of ventilation infrastructure. As heating and cooling costs are also directly linked to air volumes, the cost and energy intensity of heating and cooling the air would also be significantly reduced. A further incentive is that powering equipment from the grid is substantially cheaper than fuelling them with diesel and can also produce far fewer GHGs. Therefore, by eliminating diesel from the underground workers will enjoy safer working conditions and operators and society at large will gain from a smaller impact on the environment. Despite their significant potential, in order to produce a credible economic assessment of electric mining equipment their impact on underground systems must be understood and considered in their evaluation. Accordingly, a good deal of this thesis reviews technical considerations related to the use of electric mining equipment, especially ones that impact the economics of their implementation. The goal of this thesis will then be to present the economic potential of implementing the equipment, as well as to outline the key inputs which are necessary to support an evaluation and to provide a model and an approach which can be used by others if the relevant information is available and acceptable assumptions can be made.

From Where Do We Teach? Potential Positions in Public Education

This thesis is a conceptual examination of the positions from which we teach in public education. As it is philosophical in nature, it takes no qualitative or quantitative data. It offers a review of selected relevant literature and an analysis of personal and professional experience, with the intent to pose critical questions about teaching and learning. The framework of this thesis represents the following contentions: First, from its inception, public schooling served capital by preparing skilled labour for emerging industrial markets. This history is the hegemonic shadow that hangs over public education today. Second, movements toward the standardization of funding, curriculum, and evaluation support the further commodification of public schooling. The “accountability” that standardization offers, the “back to basics” that it aims for, is counter to the potential that public education might critically inform citizens and seek social justice. Third, movements toward the privatization of public schooling under the guise of “choice” and “mobility”, brought on by manufactured crisis, serve only to widen socio-economic inequities as capitalist neoliberal interests seek profit in both the product of public schools and in schooling itself. If we recognize and understand the power of public education to inform vast numbers of citizens who will, in turn, either maintain or reform society, we must ask: What do we want public education to be? What are the effects of continuing down historically conventional and increasingly standardized paths? What do progressive pedagogies offer? How might teachers destandardize their pedagogy and pursue equitable opportunities for marginalized students? How might students name themselves and their world, that they might play a part in its reimagining? For whom do we teach, and under what conditions? From where do we teach, and why? For educators to ask these questions, and to employ what they discover, will necessitate taking substantial risks. It will necessitate taking a stand and cannot be done alone. Teachers must seek out the collaboration of their students. They must offer students the time and the space to find their own voices, to create their own selves, and to envision previously uncharted paths on which we might walk together.