Samuel C. Morris

Toxicity of Cadmium Telluride, Copper Indium Diselenide, and Copper Gallium Diselenide

This paper reviews recently derived toxicity data for Copper Indium Diselenide (CIS), Cadmium Gallium Diselenide (CGS) and Cadmium Telluride (CT), promising new materials on which a new generation of thin-film photovoltaic cells for generating electricity may be based. The new data deal with systemic and reproductive toxicity, acute pulmonary toxicity, and comparative pulmonary absorption, distribution and toxicity of these materials in laboratory rats. CT is shown to have higher lung toxicity than CIS, with the CGS toxicity being the lowest in the group. These data are extended to human exposure levels and exposure limits for CT are derived. The implications of these findings to the photovoltaic industry are also discussed. Published in 1999 by John Wiley & Sons, Ltd. This article is a U.S. Government Work and is in the public domain in the United States.

MARKAL-MACRO: An overview

MARKAL-MACRO is an experiment in model linkage. This new tool is intended as an improvement over existing methods for energy policy assessment. It is designed specifically for estimating the costs and analyzing alternative technologies and policies proposed for reducing environmental risks such as global climate change or regional air pollution. The greenhouse gas debate illustrates the usefulness of linked energy-economy models. A central issue is the coupling between economic growth, the level of energy demands, and the evolution of an energy system to supply these demands. The debate is often connected with alternative modeling approaches. The competing philosophies may be labeled [open quotes]top-down macroeconomic[close quotes] and [open quotes]bottom-up engineering[close quotes] perspectives. Do macroeconomic models, with their descriptions of effects within the total economy but few technical details on the energy system, tend to overestimate future energy demands Conversely, do engineering models, ignoring feedbacks to the general economy and non-technical market factors but containing rich descriptions of technology options, tend to take too optimistic a view of conservation and the use of renewable energy sources Or is the principal difference that the engineering models ignore new sources of energy demands, and that the macroeconomic models ignore saturation effects for old categories of demands An efficient modeling tool must have the scope and detail to match the width and depth of the policy problem being analyzed. In order to respond to major environmental risks (e.g., the possibility of global climate changes), there must be long-range, fundamental changes in the energy system. For an analysis of these changes and an understanding of their nature, the modeling tool must be able to capture the complex network of relations within the energy system, as well as the opportunities of new or improved technologies.

The Global Carbon Dioxide Problem

Much controversy exists about effects of U.S. synthetic fuel- and coal-fired electricity generating plants on global carbon dioxide (CO2) emissions. Analyses of carbon flows through solvent refined coal (SRC-II)- and coal-fired electricity generating fuel cycles suggest that most carbon is vented to the atmosphere in each trajectory. Although the SRC-II process requires ∼50% more carbon input, the synthetic fuel trajectory produces only 20–30% more CO2 because of increased carbon input to solid waste. We estimate that proposed U.S. synthetic fuels programs could increase the global CO2 growth rate by less than 0.1% annually (e.g., 2.9 to 2.95% annual growth). In comparison, the World Meteorological Organization estimates that the CO2 growth rate could vary from <1.8 to 4.3% annually, depending on such factors as mix of fuels consumed, changes in end-use device utilization efficiencies, and modifications in energy use per capita. The effect of U.S. synthetic fuels programs is thus small in comparison to pr...

Uncertainty in risk assessment.

An analysis technique is presented for dealing with uncertainties in quantitative environmental risk analysis. Assessments of the health effects from a 1 GW sulfur-scrubbed coal-fired power plant in the upper Ohio Valley are presented. The annual average concentration of sulfate aerosol was chosen as the air pollutant of interest. The work performed was divided into three broad tasks: developing mass balance models for multiday transport, developing models to estimate population exposures, and developing models to estimate rates of mortality arising from the exposures. Leading atmospheric science and health effects experts were chosen to participate in the study.

Coal Conversion Technologies: Some Health and Environmental Effects

Several technologies to convert coal to liquid and gaseous fuels are being developed in the United States, some with support from the Department of Energy. Substitution of these technologies for those currently being used will produce different health and environmental hazards. In this article, selected health and environmental effects of four coal conversion and four existing technologies are compared. For each technology, the emission estimates for complete fuel cycles, including all steps in fuel use from extraction to the end use of space and water heating by electricity or direct combustion, were prepared by means of the Brookhaven Energy System Network Simulator model. Quantitative occupational health and safety estimates are presented for the extraction, transportation, distribution, processing, and conversion activities associated with each technology; also included are some public health damage estimates arising from fuel transportation and air pollution impacts. Qualitative estimates of health damage due to polycyclic organic matter and reduced sulfur are discussed. In general, energy inefficiencies, environmental residuals, and hence implied environmental effects and health damage increase in the order: (i) direct combustion of natural gas and oil, (ii) direct combustion of synthetic gas and oil, (iii) central-station electric power produced from synthetic gas, (iv) central-station electric power produced from coal, and (v) central-station electric power produced by the combustion of synthetic liquid fuels. The compliance and conflict of these technologies with the amendments of the Clean Air Act and other legislation are discussed.

Sulfur Control In Coal Fired Power Plants: A Probabilistic Approach to Policy Analysis

The optimum level of sulfur pollution control for a coal fired power plant is the point where the sum of societal costs, due to pollution, and control costs is minimized. This basic microeconomic concept has been of limited practical value due to considerable uncertainty in estimating both costs. A probabilistic approach is used to characterize these uncertainties quantitatively for a hypothetical 1000 Mwe plant located near Pittsburgh, Pennsylvania. Only mortality effects within a distance of 80 km of the plant have been included. The results allow explicit consideration of attitude toward risk and appropriate level of investment to prevent deaths. Limitations of the findings are discussed. Implications are described for policy based on alternative sets of values and assumptions.

Chemical emergencies: Evaluation of guidelines for risk identification, assessment, and management☆

Abstract In the wake of tragic accidents in Italy, India, Mexico City, and elsewhere, the Council of European Communities, the International Labour Organisation, the U.S. Environmental Protection Agency, and the World Bank have each issued guidelines for identifying, assessing, and managing risks from major hazards at industrial facilities. These guidelines are examined and compared. All treat the general problem in similar ways. Presence of a specific compound exceeding that thought to present a potential hazard to public health triggers further action. But, there are different “threshold quantities” among these guidelines due to different interpretations about such factors as toxicity and dispersive potential. A problem common to all guidelines is their failure to deal quantitatively with probabilities of accidents. Development of additional screening methods is recommended.

Oxidant Air Pollution: A Model for Estimating Effects on U.S. Vegetation

Brookhaven National Laboratory has critically evaluated the structure and results of the Stanford Research Institute model (SRI model) for assessing national-level economic impacts of oxidants on plants. In response to inherent weaknesses in the SRI approach, a new model (DAMAGE) was constructed to estimate national-level damage from oxidants for alfalfa. DAMAGE uses actual oxidant measurements and the Oshima dose-response function for alfalfa to estimate effects on yield. Economic loss is then simply calculated by multiplying crop value by percent loss. Estimates of oxidant effects on alfalfa in 1974 were calculated with both DAMAGE and the SRI model. Results of the SRI model closely approach those of DAMAGE when the dose estimate is approximated by the seasonal total of the hourly averages. Other methods of estimating dose in DAMAGE give distinctly higher estimates of economic loss. The lower bound estimates suggest losses equal to

Needed: A National R&D Effort To Develop Individual Air Pollution Monitor Instrumentation

20 million or 4% of the total yield in the counties examined. Upper est...

Personal monitoring of air pollution exposures

(1977). Needed: A National R&D Effort To Develop Individual Air Pollution Monitor Instrumentation. Journal of the Air Pollution Control Association: Vol. 27, No. 7, pp. 670-673.