William Lilley

Measurement and modelling of pollutant emissions from Hong Kong

Abstract During November 1997 a detailed airborne investigation of air pollution in the Hong Kong region was undertaken. The airborne investigation formed part of a larger study funded by the Hong Kong Environmental Protection Department (EPD) and included the development of a state of the art numerical air quality modelling system to simulate air pollution in the Hong Kong region. The system consisted of a numerical weather prediction module, a prognostic air–chemistry/transport model, an emissions inventory system and a Graphical User Interface for display of results and preparation of simulations. The purpose of the airborne investigations was to provide data on the fluxes of selected pollutants arising from or entering the Hong Kong airshed as a check on the inventory. In addition the aircraft was to provide data on other pollutants of interest particularly with respect to the formation of photochemical smog. This paper describes the inventory data obtained from the aircraft and makes comparisons between the predictions of the model and the aircraft data for one of the days when the aircraft was able to be used to estimate the total fluxes of NMHC and NOx from the study area.

A comparison of three methods for the quantification of greenhouse gas emissions from spontaneous combustion in open-cut coal mines

Greenhouse gas emissions from spontaneous combustion in coal mines are currently excluded from national inventories by the United Nations Framework Convention on Climate Change because there are no robust methods available to quantify the emissions. This article reports on investigations of three approaches being pursued with the aim of developing methods which are sufficiently robust to enable these emissions to be included in inventories. The first method was based on the use of airborne thermal infrared photography coupled with chamber measurements of emissions from hot mine spoil pile surfaces. In the second method, crosswind traverses of the plume using an instrumented vehicle were used to estimate the emission fluxes. The third method was based on inverse atmospheric modelling using stationary CO2 monitors. All three methods showed considerable scatter in their estimates but also showed appreciable overlap. While the three methods used in this study have shown convergence, there is still considerable uncertainty associated with any single approach.

A randomised cross-over cohort study of exposure to emissions from a road tunnel ventilation stack.

Background and objective Road tunnels are increasingly important components of urban infrastructure. However, knowledge of their health impact on surrounding communities is limited. Our objective was to estimate the short-term respiratory health effects of exposure to emissions from a road tunnel ventilation stack. Methods We conducted a randomised cross-over cohort study in 36 volunteers who underwent three exposure scenarios in 2006 before the road tunnel opened, and in 2007 (n=27) and 2008 (n=20) after the tunnel opened. Exposure downwind of the stack was compared to upwind of the stack and to a distant heavily trafficked location adjacent to a main road. Spirometry, exhaled nitric oxide (eNO) and symptom scores were measured repeatedly during each 2 h exposure session. Results Downwind locations were associated with increased reports of ‘dry nose’ (score difference 0.36; 95% CI 0.09 to 0.63) compared with the control location (2006 vs 2007/2008), but not with impaired lung function, increased airway inflammation or other symptoms. The heavily trafficked location was associated with significantly increased eNO (ratio=1.09; 95% CI 1.04 to 1.14), eye (score difference 0.05; 95% CI 0.01 to 0.10) and chest (score difference 0.21; 95% CI 0.09 to 0.33) symptoms compared to the stack locations. Conclusions There was no consistent evidence of adverse respiratory effects from short-term exposures downwind of the tunnel ventilation stack, except for dry nose symptoms. However, the findings of increased airway inflammation and symptoms in subjects after only 2 h exposure at the heavily trafficked location, are suggestive of detrimental effects of short-term exposures to traffic-related air pollution.

Realizing the Potential of Renewable and Distributed Generation

Publisher Summary This chapter provides the results of a modeling analysis that considers the value that smart grids may provide by enabling the increased use of intermittent renewable and distributed generation. Modeling clearly shows that savings from allowing an increased proportion of intermittent renewable and distributed generation can be very significant when considering how the world may meet the dual challenge of reducing emissions of greenhouse gases while accommodating the ongoing growth in demand. These savings are only realized by considering the long-term change to energy supply because of the lifetimes of the assets involved. This has important implications for smart grid use, planning, and development, which will be needed to ensure these renewable technologies reach their full potential. The more traditionally noted benefits such as increased reliability, security, and consumer awareness, the development of a smart grid appears to be a very favorable mechanism to help the world reduce its green- house gas emissions while maintaining current levels of supply enjoyed in many of the worlds developed countries.

Chapter 1 – Spontaneous Combustion in Open-Cut Coal Mines: Australian Experience and Research

Spontaneous combustion results from self-heating caused mainly by low temperature oxidation of coal and other carbonaceous materials. In open-cut coal mines large quantities of carbonaceous waste material are disposed of in spoil piles within the mine site. Some of this material may be sufficiently reactive to begin to self-heat which can ultimately lead to spontaneous combustion in the spoil piles if not properly managed. Uncontrolled fires in spoil piles present a number of problems including safety hazards for mine personnel, the production of toxic gases, damage to rehabilitated land, and emission of greenhouse gases. Although a great deal of research into spontaneous combustion in coal has been conducted over many years, there has been comparatively little investigation of carbonaceous materials in spoil piles. In this chapter, some research aimed specifically at understanding self-heating and spontaneous combustion in spoil materials is reviewed, especially in the context of Australian open-cut coalmines. The principal conclusions of this work and resultant mine site management practices developed to minimize the occurrence of self-heating are discussed.

Exploring the Value of Distributed Energy for Australia

This chapter examines the important role that distributed energy (DE) can play in smart grids in Australia to achieve a low carbon future. It discusses the findings of a recent major government-funded study which showed that uptake of DE could result in potential economic savings of around

Proposed Road Pollution Alert System Based on Lagrangian Wall Model

130 billion by 2050. It also provides updates of more recent modelling that takes into account sensitivities in the price of natural gas and the price of solar photovoltaic (PV). This chapter further examines the key issues, opportunities and challenges of realising the value of DE in Australia. The analysis highlights the importance of integrating DE with the electricity grid and urban environment and discusses enablers and barriers for large-scale uptake of DE.

An economic evaluation of the potential for distributed energy in Australia

Despite significant improvements in fuel and engine technology, road traffic remains a major source of air pollutants, such as oxides of nitrogen, CO, particulate matter, and volatile organic compounds. Many recent studies have demonstrated associations between traffic-related air pollution and the adverse effects of exposure to traffic-related air pollution in a wide variety of situations. This paper describes the components of a proposed road pollution modeling-and-alert system that can be deployed by local authorities on sections of roads that are under the continuous risk of exceeding thresholds of acceptable air quality. The system features the use of real-time traffic data from intelligent transportation systems and related sources; a power-based model for the calculation of emissions that takes into account the driving mode of the vehicle as well as characteristics of the road segment; a Lagrangian wall model (LWM) to simulate the dispersion of pollutants from different sources; and an alert-and-response system that will need further input from government authorities, industry, and the community. The ability to combine emissions estimates from a power-based motor vehicle emissions model with the LWM dispersion and chemical transformation capabilities significantly enhances the capacity to minimize population exposure and reduce health impacts of pollution from particular roads of interest. This paper discusses development of the LWM and summarizes outcomes of a verification study performed with the California Department of Transportation Highway 99 tracer dispersion data set. It also presents results of a case study performed to demonstrate capabilities of the LWM.