Stress parameters and behaviour of horses in walkers with and without the use of electricity

In order to investigate stress responses of horses in walkers with and without electricity, 12 horses were trained during 3 weeks in a horse walker with and without the use of electricity (3.7 kV). To evaluate the stress response, cortisol levels in the blood were measured, the heart rate was monitored using the Polar® system and the behaviour was evaluated. Neither the cortisol levels nor the heart rates showed any relevant statistically significant difference between horses moved in the horse walker with or without the use of electricity. The highest cortisol levels and heart rates were recorded during the first week (habituation period). A significant difference could be observed regarding spontaneous compartment changes: while this happened mainly during the first week and before the first use of electricity, no horses changed compartments in the periods when electricity was used and thereafter. The results of this study indicate that the use of electricity in the horse walker does not seem to cause significant detectable stress in the horses.

Game Theoretic Bidding Strategies for Auctions in Green Electricity Markets

Electricity markets in the United States presently employ an auction mechanism to determine the dispatch of power generation units. In this market design, generators submit bid prices to a regulation agency for review, and the regulator conducts an auction selection in such a way that satisfies electricity demand. Most regulators currently use an auction selection method that minimizes total offer costs ["bid cost minimization" (BCM)] to determine electric dispatch. However, recent literature has shown that this method may not minimize consumer payments, and it has been shown that an alternative selection method that directly minimizes total consumer payments ["payment cost minimization" (PCM)] may benefit social welfare in the long term. The objective of this project is to further investigate the long term benefit of PCM implementation and determine whether it can provide lower costs to consumers. The two auction selection methods are expressed as linear constraint programs and are implemented in an optimization software package. Methodology for game theoretic bidding simulation is developed using EMCAS, a real-time market simulator. Results of a 30-day simulation showed that PCM reduced energy costs for consumers by 12%. However, this result will be cross-checked in the future with two other methods of bid simulation as proposed in this paper.

Strategic Behavior in Day-Ahead and Real-Time Markets for Electricity: Offer Cost or Payment Cost Minimization?

This study compares the procurement cost-minimizing and productive efficiency performance of the auction mechanism used by independent system operators (ISOs) in wholesale electricity auction markets in the U.S. with that of a proposed alternative. The current practice allocates energy contracts as if the auction featured a discriminatory final payment method when, in fact, the markets are uniform price auctions. The proposed alternative explicitly accounts for the market clearing price during the allocation phase. We find that the proposed alternative largely outperforms the current practice on the basis of procurement costs in the context of simple auction markets featuring both day-ahead and real-time auctions and that the procurement cost advantage of the alternative is complete when we simulate the effects of increased competition. We also find that a trade-off between the objectives of procurement cost minimization and productive efficiency emerges in our simple auction markets and persists in the face of increased competition.

Efficiency in Deregulated Electricity Markets: Offer Cost Minimization vs. Payment Cost Minimization Auction

This study of the wholesale electricity market compares the efficiency performance of the auction mechanism currently in place in U.S. markets with the performance of a proposed mechanism. The analysis highlights the importance of considering strategic behavior when comparing different institutional systems. We find that in concentrated markets, neither auction mechanism can guarantee an efficient allocation. The advantage of the current mechanism increases with increased price competition if market demand is perfectly inelastic. However, if market demand has some responsiveness to price, the superiority of the current auction with respect to efficiency is not that obvious. We present a case where the proposed auction outperforms the current mechanism on efficiency even if all offers reflect true production costs. We also find that a market designer might face a choice problem with a tradeoff between lower electricity cost and production efficiency. Some implications for social welfare are discussed as well.

Simple-Offer vs. Complex-Offer Auctions in Deregulated Electricity Markets

In my recent experimental research of wholesale electricity auctions, I discovered that the complex structure of the offers leaves a lot of room for strategic behavior, which consequently leads to anti- competitive and inefficient outcomes in the market. A specific feature of these complex-offer auctions is that the sellers submit not only the quantities and the minimum prices at which they are willing to sell, but also the start-up fees that are designed to reimburse the fixed start-up costs of the generation plants. In this paper, using the experimental method I compare the performance of two complex-offer auctions (COAs) against the performance of a simple-offer auction (SOA), in which the sellers have to recover all their generation costs --- fixed and variable ---through a uniform market-clearing price. I find that the SOA significantly reduces consumer prices and lowers price volatility. It mitigates anti-competitive effects that are present in the COAs and achieves allocative efficiency more quickly.

Can a Newly Proposed Mechanism for Allocating Contracts in U.S. Electricity Wholesale Markets Lead to Lower Prices? A Game Theoretic Analysis

This study of the wholesale electricity market compares the cost-minimizing performance of the auction mechanism currently in place in U.S. markets with the performance of a proposed replacement. The current mechanism chooses an allocation of contracts that minimizes a fictional cost calculated using pay-as-offer pricing. Then suppliers are paid the market clearing price. The proposed mechanism uses the market clearing price in the allocation phase as well as in the payment phase. In concentrated markets, the proposed mechanism outperforms the current mechanism even when strategic behavior by suppliers is taken into account. The advantage of the proposed mechanism increases with increased price competition.

Thomas Britton. A Small-Coal-man.

Signatur des Originals: S 36/G00549

Analysis of participation in the federally mandated coal workers' health surveillance program

The Federal Coal Mine Health and Safety Act of 1969 required that periodic chest radiographs be offered to underground coal miners to protect the miners from the development of Coal Workers' Pneumoconiosis (CWP) and progression of the disease to progressive massive fibrosis (PMF). These examinations are administered by the National Institute for Occupational Safety and Health (NIOSH) through the Coal Workers' Health Surveillance Program (CWHSP). The mine operator is required to provide each miner with the opportunity to have the chest radiograph at no cost to the miner.^ Three rounds of examinations have been conducted since 1969 and the fourth is underway. The decrease in participation over rounds is of great concern if the incidence and progression of CWP are to be understood and controlled.^ This study developed rates of participation for each of 558 West Virginia underground coal mines who submitted or had NIOSH assigned plans for making chest radiographs available during the third round, July 1978 through December 1980. These rates were analyzed in relation to desired levels of participation and to reinforcing, predisposing and enabling factors presumed to affect rates of participation in disease prevention and surveillance programs.^ Two reinforcing factors, size of mine and inclusion of the mine in the National Coal Study (NCS) epidemiology research program, and the enabling factor, use of an on-site radiograph facility, demonstrated highly significant relationships to participation rates.^ The major findings of the study were: (1) Participation in the CWHSP is even lower than previously estimated; (2) CWHSP program evaluation is not systematic and program data base is not complete and comprehensive; and (3) NIOSH program policy is not clear and administration of the CWHSP is fragmented and lacks adequate fiscal and personnel resources. ^

DEVELOPMENT AND APPLICATION OF SHORT-TERM MUTAGENICITY AND CYTOTOXICITY BIOASSAYS FOR INTEGRATED HEALTH ASSESSMENT STUDIES OF COAL FLY ASH EMISSIONS

Two respirable coal fly ash samples ((LESSTHEQ) 3(mu)m), one from a pressurized fluidized-bed combustion miniplant and one from a conventional combustion power plant, were investigated for physical properties, chemical composition and biological activity. Electron microscopy illustrated irregularity in fluidized-bed combustion fly ash and sphericity in conventional combustion fly ash. Elemental analysis of these samples showed differences in trace elements. Both fly ash samples were toxic in rabbit alveolar macrophage and Chinese hamster ovary cell systems in vitro. The macrophages were more sensitive to toxicity of fly ash than the ovary cells. For measuring the cytotoxicity of fly ash, the most sensitive parameters were adenosine triphosphate in the alveolar macrophage system and viability index in the hamster ovary system. Intact fluidized-bed combustion fly-ash particles showed mutagenicity only in strains TA98 and TA1538 without metabolic activation in the Ames Salmonella assay. No mutagenicity was detected in bioassay of conventional combustion fly ash particles. Solvent extraction yielded more mass from fluidized-bed combustion fly ash than from conventional combustion fly ash. The extracts of fluidized-bed combustion fly ash showed higher mutagenic activity than conventional combustion fly ash. These samples contained direct-acting, frameshift mutagens.^ Fly ash samples collected from the same fluidized-bed source by cyclones, a fabric filter, and a electrostatic precipitator at various temperatures were compared for particle size, toxicity, and mutagenicity. Results demonstrated that the biological activity of coal fly ash were affected by the collection site, device, and temperature.^ Coal fly ash vapor-coated with 1-nitropyrene was developed as a model system to study the bioavailability and recovery of nitroaromatic compounds in fly ash. The effects of vapor deposition on toxicity and mutagenicity of fly ash were examined. The nitropyrene coating did not significantly alter the ash's cytotoxicity. Nitropyrene was bioavailable in the biological media, and a significant percentage was not recovered after the coated fly ash was cultured with alveolar macrophages. 1-Nitropyrene loss increased as the number of macrophages was increased, suggesting that the macrophages are capable of metabolizing or binding 1-nitropyrene present in coal fly ash. ^

RUNOFF FROM COAL PILES: EFFECTS ON THE ENVIRONMENT AND THE PUBLIC'S HEALTH

The use of coal for fuel in place of oil and natural gas has been increasing in the United States. Typically, users store their reserves of coal outdoors in large piles and rainfall on the coal creates runoffs which may contain materials hazardous to the environment and the public's health. To study this hazard, rainfall on model coal piles was simulated, using deionized water and four coals of varying sulfur content. The simulated surface runoffs were collected during 9 rainfall simulations spaced 15 days apart. The runoffs were analyzed for 13 standard water quality parameters, extracted with organic solvents and then analyzed with capillary column GC/MS, and the extracts were tested for mutagenicity with the Ames Salmonella microsomal assay and for clastogenicity with Chinese hamster ovary cells.^ The runoffs from the high-sulfur coals and the lignite exhibited extremes of pH (acidity), specific conductance, chemical oxygen demand, and total suspended solids; the low-sulfur coal runoffs did not exhibit these extremes. Without treatment, effluents from these high-sulfur coals and lignite would not comply with federal water quality guidelines.^ Most extracts of the simulated surface runoffs contained at least 10 organic compounds including polycyclic aromatic hydrocarbons, their methyl and ethyl homologs, olefins, paraffins, and some terpenes. The concentrations of these compounds were generally less than 50 (mu)g/l in most extracts.^ Some of the extracts were weakly mutagenic and affected both a DNA-repair proficient and deficient Salmonella strain. The addition of S9 decreased the effect significantly. Extracts of runoffs from the low-sulfur coal were not mutagenic.^ All extracts were clastogenic. Extracts of runoffs from the high-sulfur coals were both clastogenic and cytotoxic; those from the low-sulfur coal and the lignite were less clastogenic and not cytotoxic. Clastogenicity occurred with and without S9 activation. Chromosomal lesions included gaps, breaks and exchanges. These data suggest a relationship between the sulfur content of a coal, its mutagenicity and also its clastogenicity.^ The runoffs from actual coal piles should be investigated for possible genotoxic effects in view of the data presented in this study.^

Chemical characteristics of coal pebbles and Barzas-type coals

Coal pebbles found in 1994 in the Greham Bell Island (Franz Josef Land Archipelago) are made up of Barzas-type cuticular liptobiolith. The coal belongs to the initial stage of catagenesis and is characterized by high content of cutinite (up to 70%) with very low reflectance (Ro = 0.1%). Maceration products show some tegillate elements of Arthropoda and individual Devonian spores. It is supposed that plant cuticle and Arthropoda exocuticle are present in this coal. Obtained data suggest presence of Paleozoic rocks in the sedimentary sequence, although they are not yet recovered. These data complement available information on distribution of specific Devonian coals and allow to have a new insight into zoogenic material involved in coal formation.

Geochemistry and mineralogy of coal samples from Dingji Mine, Huainan Coalfield, China

To investigate the geochemistry of trace elements in coals from the Dingji Mine of the Huainan Coalfield, Anhui province, China, 416 borehole samples of coal, one parting, two floor and two roof mudstones were collected from 9 minable coal seams in 24 boreholes drilled during exploration. The abundances of 47 elements in each sample were determined by various instruments. The boron concentration in the coals suggests that marine influence decreased from coal seam 1 to 13-1. The geometric means of the elements Sn, Bi, Sb, and B are higher than the average for the corresponding elements in the coals from China, the U.S., and world. The enrichment of certain elements in the Shanxi or Upper Shihezi Formations is related to their depositional environment. The roof, floor and parting samples have higher contents of some elements than coal seams. The mineral matters in the coals from the Dingji Mine were found to consist mainly of granular quartz, clay minerals, and carbonate minerals. The elements are classified into two groups based on their stratigraphic distribution from coal seam 1 to 13-1, and the characteristics of each group are discussed. Based on the correlation coefficients of elemental concentrations with ash yield, four groups of elements with different affinities were identified.

Greening electricity through taxing: An analysis of GATT constraints

This paper examines the legal feasibility of different design options for implementing a differentiated electricity tax based on renewable energy (RE) certificates aimed at promoting green electricity generation. It discusses the issue of likeness in light of the recent WTO jurisprudence and looks at the possibility of justification of differentiated tax rates under the general exceptions of the GATT. It also scrutinizes the potential legal hurdles for the implementation of different tax design options including the use of certificates for RE tax exemption. It argues that the placing of a quota on the number of foreign RE certificates eligible for tax exemptions would likely affect the volumes of imported green electricity and therefore trigger a violation of GATT rules. At the same time, restrictions on the eligibility of RE certificates might be defended under WTO law if they are based on qualitative criteria, such as the attachment of RE certificates to green electricity flows or to a green electricity label that is equally available to domestic and foreign suppliers of RE electricity.