Health Impacts of Power-Exporting Plants in Northern Mexico

In the past two decades, rapid population and economic growth on the U.S.–Mexico border has spurred a dramatic increase in electricity demand. In response, American energy multinationals have built power plants just south of the border that export most of their electricity to the United States. This development has stirred considerable controversy because these plants effectively skirt U.S. environmental air pollution regulations in a severely degraded international airshed. Yet to our knowledge, this concern has not been subjected to rigorous scrutiny. This paper uses a suite of air dispersion, health impacts, and valuation models to assess the human health damages in the United States and Mexico caused by air emissions from two power-exporting plants in Mexicali, Baja California. We find that these emissions have limited but nontrivial health impacts, mostly by exacerbating particulate pollution in the United States, and we value these damages at more than half a million dollars per year. These findings demonstrate that power-exporting plants can have cross-border health effects and bolster the case for systematically evaluating their environmental impacts.electricity, air pollution, Mexico

Health Impacts of Power-Exporting Plants in Northern Mexico

In the past two decades, rapid population and economic growth on the U.S.–Mexico border has spurred a dramatic increase in electricity demand. In response, American energy multinationals have built power plants just south of the border that export most of their electricity to the United States. This development has stirred considerable controversy because these plants effectively skirt U.S. environmental air pollution regulations in a severely degraded international airshed. Yet to our knowledge, this concern has not been subjected to rigorous scrutiny. This paper uses a suite of air dispersion, health impacts, and valuation models to assess the human health damages in the United States and Mexico caused by air emissions from two power-exporting plants in Mexicali, Baja California. We find that these emissions have limited but nontrivial health impacts, mostly by exacerbating particulate pollution in the United States, and we value these damages at more than half a million dollars per year. These findings demonstrate that power-exporting plants can have cross-border health effects and bolster the case for systematically evaluating their environmental impacts.electricity, air pollution, Mexico

Potential for non-road modes to support environmentally friendly urban logistics

Road freight transport typically dominates in urban delivery operations. However, an increasing number of trials and commercial operations have started in the past 10 years attempting to use non-road modes in a wide range of cities including: Paris, Berlin, Madrid, Amsterdam and others. The research establishes the existing scale of rail freight in two comparable cities (London and Paris/Ile de France) and compares the development process in terms of the stakeholders, the infrastructure and planning issues and the nature of the operations. The review considers the scope and opportunity for an increase in the use of rail for urban freight transport and assesses the barriers to its wider implementation. The research is based on a mixture of desk research examining a number of cities and their use of rail freight transport combined with some interviews with the major stakeholders. The research contains an assessment of a number of pilot projects and initiatives that can be considered together and offer important insights into the potential for changes to urban distribution operations. The findings illustrate that rail plays a more important part than is often thought but that its uptake is restricted by the complex barriers to wider implementation. Planning limits and the complexity of engaging with the range of stakeholders has made it difficult to implement rail solutions for urban freight. It is clear that some of the developments can be considered as filling a rather narrow niche function. However, it is also apparent that some initiatives have the scope for wider implementation and to contribute significantly to reducing the reliance on road freight transport in cities. The analysis will support the work of urban planners and policy makers concerned with how to reach the EU target of essentially zero CO2 urban freight by 2030. In addition, the research identifies a number of barriers that need to be overcome and proposes ways to achieve this

Effect of laser-welding parameters on the heat input and weld-bead profile

Laser butt-welding of medium carbon steel was investigated using CW 1.5 kW CO2 laser. The effect of laser power (1.2 - 1.43 kW), welding speed (30 - 70 cm/min) and focal point position (-2.5 - 0 mm) on the heat input and the weld-bead geometry (i.e. penetration (P), welded zone width (W) and heat affected zone width (WHAZ)) was investigated using Response Surface Methodology (RSM). The experimental plan was based on Box-Behnken design. Linear and quadratic polynomial equations for predicting the heat input and the weld-bead geometry were developed. The results indicate that the proposed models predict the responses adequately within the limits of welding parameters being used. It is suggested that regression equations can be used to find optimum welding conditions for the desired criteria

Effect of magnetic and non-magnetic impurities on highly anisotropic superconductivity

We generalize Abrikosov-Gor'kov solution of the problem of weakly coupled superconductor with impurities on the case of a multiband superconductor with arbitrary interband order parameter anisotropy, including interband sign reversal of the order parameter. The solution is given in terms of the effective (renormalized) coupling matrix and describes not only $T_c$ suppression but also renormalization of the superconducting gap basically at all temperatures. In many limiting cases we find analytical solutions for the critical temperature suppression. We illustrate our results by numerical calculations for two-band model systems.Comment: 18 pages (12pt) RevTeX, 4 postscript figure