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In September 2015, the Volkswagen Group (VW) admitted the use of 'defeat devices' designed to lower emissions measured during VW vehicle testing for regulatory purposes. Globally, 11 million cars sold between 2008 and 2015 are affected, including about 2.6 million in Germany. On-road emissions tests have yielded mean on-road NO[subscript x] emissions for these cars of 0.85 g km[superscript −1], over four times the applicable European limit of 0.18 g km[superscript −1]. This study estimates the human health impacts and costs associated with excess emissions from VW cars driven in Germany. A distribution of on-road emissions factors is derived from existing measurements and combined with sales data and a vehicle fleet model to estimate total excess NO[subscript x] emissions. These emissions are distributed on a 25 by 28 km grid covering Europe, using the German Federal Environmental Protection Agency's (UBA) estimate of the spatial distribution of NO[subscript x] emissions from passenger cars in Germany. We use the GEOS-Chem chemistry-transport model to predict the corresponding increase in population exposure to fine particulate matter and ozone in the European Union, Switzerland, and Norway, and a set of concentration-response functions to estimate mortality outcomes in terms of early deaths and of life-years lost. Integrated over the sales period (2008–2015), we estimate median mortality impacts from VW excess emissions in Germany to be 1200 premature deaths in Europe, corresponding to 13 000 life-years lost and 1.9 billion EUR in costs associated with life-years lost. Approximately 60% of mortality costs occur outside Germany. For the current fleet, we estimate that if on-road emissions for all affected VW vehicles in Germany are reduced to the applicable European emission standard by the end of 2017, this would avert 29 000 life-years lost and 4.1 billion 2015 EUR in health costs (median estimates) relative to a counterfactual case with no recall., Germany. Umweltbundesamt (UBA)

In September 2015, the Volkswagen Group (VW) admitted the use of 'defeat devices' designed to lower emissions measured during VW vehicle testing for regulatory purposes. Globally, 11 million cars sold between 2008 and 2015 are affected, including about 2.6 million in Germany. On-road emissions tests have yielded mean on-road NO[subscript x] emissions for these cars of 0.85 g km⁻¹, over four times the applicable European limit of 0.18 g km⁻¹. This study estimates the human health impacts and costs associated with excess emissions from VW cars driven in Germany. A distribution of on-road emissions factors is derived from existing measurements and combined with sales data and a vehicle fleet model to estimate total excess NO[subscript x] emissions. These emissions are distributed on a 25 by 28 km grid covering Europe, using the German Federal Environmental Protection Agency's (UBA) estimate of the spatial distribution of NO[subscript x] emissions from passenger cars in Germany. We use the GEOS-Chem chemistry-transport model to predict the corresponding increase in population exposure to fine particulate matter and ozone in the European Union, Switzerland, and Norway, and a set of concentration-response functions to estimate mortality outcomes in terms of early deaths and of life-years lost. Integrated over the sales period (2008–2015), we estimate median mortality impacts from VW excess emissions in Germany to be 1200 premature deaths in Europe, corresponding to 13 000 life-years lost and 1.9 billion EUR in costs associated with life-years lost. Approximately 60% of mortality costs occur outside Germany. For the current fleet, we estimate that if on-road emissions for all affected VW vehicles in Germany are reduced to the applicable European emission standard by the end of 2017, this would avert 29 000 life-years lost and 4.1 billion 2015 EUR in health costs (median estimates) relative to a counterfactual case with no recall.

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016., This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections., Cataloged from student-submitted PDF version of thesis., Includes bibliographical references (pages 140-161)., Air transportation is an integral part of the economy and the transportation infrastructure. However, aircraft activity at airports generates CO2 emissions that affect the climate and other pollutants that affect air quality and human health. The focus of this thesis is to enable the reduction of the air quality impacts of aircraft operations at airports by (1) advancing the understanding of the relationship between aircraft activity and its air quality impacts and (2) evaluating the air quality benefits of controlling aircraft operations. There are atmospheric conditions where decreasing fuel burn (which is directly proportional to CO2 emissions) results in increased population exposure to fine particulate matter (PM2.5) and ozone (O3). This thesis quantifies the duration and magnitude of the tradeoffs between CO2 emissions and population exposure. The research complements current studies that optimize aircraft operations at airports for CO2 emissions but have not quantified the air quality implications of doing so. This raises the possibility of reducing the air quality impacts of airports beyond focusing only on minimizing fuel burn. Next, this thesis characterizes the atmospheric conditions that give rise to tradeoffs between emissions and population exposure to ozone. The ozone exposure response to nitrogen oxide (NOx) and Volatile Organic Compound (VOC) emissions is quantified as a function of ambient NOx and VOC concentrations using ozone exposure isopleths. This is the first time that ozone exposure isopleths are created for all locations in the US, using emission sensitivities from the adjoint of an air quality model. Metrics are calculated based on the isopleths which can be used to determine whether NOx and VOC emission reductions will improve ozone exposure or be counter-productive and the optimal NOx/VOC reduction ratio. Finally, this thesis calculates, for the first time, the air quality and climate benefits of pushback control and de-rated takeoffs fo, by Akshay Ashok., Ph. D.

The US Environmental Protection Agency (EPA) has alleged that Volkswagen Group of America (VW) violated the Clean Air Act (CAA) by developing and installing emissions control system 'defeat devices' (software) in model year 2009–2015 vehicles with 2.0 litre diesel engines. VW has admitted the inclusion of defeat devices. On-road emissions testing suggests that in-use NO[subscript x] emissions for these vehicles are a factor of 10 to 40 above the EPA standard. In this paper we quantify the human health impacts and associated costs of the excess emissions. We propagate uncertainties throughout the analysis. A distribution function for excess emissions is estimated based on available in-use NO[subscript x] emissions measurements. We then use vehicle sales data and the STEP vehicle fleet model to estimate vehicle distance traveled per year for the fleet. The excess NO[subscript x] emissions are allocated on a 50 km grid using an EPA estimate of the light duty diesel vehicle NO[subscript x] emissions distribution. We apply a GEOS-Chem adjoint-based rapid air pollution exposure model to produce estimates of particulate matter and ozone exposure due to the spatially resolved excess NO[subscript x] emissions. A set of concentration-response functions is applied to estimate mortality and morbidity outcomes. Integrated over the sales period (2008–2015) we estimate that the excess emissions will cause 59 (95% CI: 10 to 150) early deaths in the US. When monetizing premature mortality using EPA-recommended data, we find a social cost of ~$450m over the sales period. For the current fleet, we estimate that a return to compliance for all affected vehicles by the end of 2016 will avert ~130 early deaths and avoid ~$840m in social costs compared to a counterfactual case without recall.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2011., This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections., Cataloged from student submitted PDF version of thesis., Includes bibliographical references (p. 104-112)., The rapid growth of aviation is critical to the world and US economy, and it faces several important challenges among which lie the environmental impacts of aviation on noise, climate and air quality. The first objective of this thesis addresses the requirements of section 753 of the US Energy Policy Act, and entails the quantification of present and future-year regional air quality impacts of US Landing and Take-Off (LTO) aviation emissions. In addition, this thesis characterizes the sensitivity of these impacts to variations in the projection of non-aviation anthropogenic emissions (referred to as background emissions). Finally, the implication of a future-year background emissions scenario on the current policy analysis tool, the response surface model (RSMv2), is discussed. Aviation emissions for 2006 are generated using the Aviation Environmental Design Tool (AEDT), while future-year aviation emissions are developed for 2020 and 2030 using the Federal Aviation Administration (FAA) Terminal Area Forecast (TAF) and the International Civil Aviation Organization (ICAO) Committee on Aviation Environmental Protection (CAEP/8) NOx Stringency scenario #6. Background emissions for the year 2005 and 2025 are generated from the US Environmental Protection Agency (EPA) National Emissions Inventory (NEI), and two additional sensitivity scenarios are derived from the emissions forecasts. Uncertainties in present and forecast aviation and background emissions are also characterized. The Community Multiscale Air Quality (CMAQ) model is evaluated to quantify its performance in predicting ambient PM2.5 and ozone concentrations, and it is used to estimate aviation air quality impacts of aviation. Future-year aviation particulate matter (PM2.5) concentrations are found to increase by a factor of 2 and 2.4 by 2020 and 2030, and are dominated by nitrate and ammonium PM. Aviation 8-hour daily maximum ozone is seen to grow by a factor of 1.9 and 2.2 by 2020 and 2030, with non-homogene, by Akshay Ashok., S.M.

Capacitively coupled radio frequency discharges are used in a variety of applications in which the power transmission efficiency of the discharge is an important performance parameter. While previous research addressed the discharge properties and discharge modeling, little analysis has been done on the dependence of the power transmission efficiency on main discharge paremeters such as applied voltage, operating frequency and pressure. To investigate the effects of a dual frequency waveform on the power transmission efficiency, Particle-InCell/Monte-Carlo Collison (PIC/MCC) methods are used to simulate RF co-axial plasma discharge. Plasma characteristics are studied for a range of operating pressures and radii, as electrode voltages were varied between 0, 100 and 250V. The investigation concludes that the addition of a RF power source to the outer electrode increase power transmission efficiency by about 100%. Power transmission efficiency increases with a decrease in radius and an increase in pressure, in general. Low-frequency high-voltage power source combination is found to generate a more efficient discharge than a high-frequency high-voltage power source.