• Energy Research
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This report takes a broad look at the status of local clean energy policies in the United States to develop a better understanding of local clean energy policy development and the interaction between state and local policies. To date, the majority of clean energy policy research focuses on the state and federal levels. While there has been a substantial amount of research on local level climate change initiatives, this is one of the first analyses of clean energy policies separate from climate change initiatives. This report is one in a suite of reports analyzing clean energy and climate policy development at the local, state, and regional levels.

Exchanging heat from hot geothermal fluid to a secondary working fluid which is then expanded through a turbine appears to be the best way of producing electrical power from a medium temperature geothermal resource. A study has been made to determine the conceptual design state points for a dual boiling system which utilizes isobutane as the working fluid. The results of this work and the sensitivity of plant performance to variations from nominal design points are presented. In addition, variations due to tolerances applied to thermodynamic properties and other key factors are included. (auth)

Program planning support was provided by; developing a geothermal RD and D program structure, characterizing the status of geothermal RD and D through review of literature and interaction with the geothermal research community, developing a candidate list of future Texas geothermal projects, and prioritizing the candidate projects based on appropriate evaluation criteria. The method used to perform this study and the results thereof are presented. Summary reviews of selected completed and ongoing projects and summary descriptions and evaluations of the candidate RD and D projects ar provided. A brief discussion emerging federal RD and D policies is presented. References and independent project rankings by three of the GRP members are included. (MHR)

Vanadium-containing glasses have aroused interest in several fields such as electrodes for energy storage, semiconducting glasses, and nuclear waste disposal. The addition of V2O5, even in small amounts, can greatly alter the physical properties and chemical durability of glasses; however, the structural role of vanadium in these multicomponent glasses and the structural origins of these property changes are still poorly understood. We present a comprehensive study that integrates advanced characterizations and atomistic simulations to understand the composition-structure-property relationships of a series of vanadium-containing aluminoborosilicate glasses. UV-vis spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure (XANES) have been used to investigate the complex distribution of vanadium oxidation states as a function of composition in a series of six-component aluminoborosilicate glasses. High-energy X-ray diffraction and molecular dynamics simulations were performed to extract the detailed short- and medium-range atomistic structural information such as bond distance, coordination number, bond angle, and network connectivity, based on recently developed vanadium potential parameters. It was found that vanadium mainly exists in two oxidation states: V5+ and V4+, with the former being dominant (∼80% from XANES) in most compositions. V5+ ions were found to exist in 4-, 5-, and 6-fold coordination, while V4+ ions were mainly in 4-fold coordination. The percentage of 4-fold-coordinated boron and network connectivity initially increased with increasing V2O5 up to around 5 mol % but then decreased with higher V2O5 contents. The structural role of vanadium and the effect on glass structure and properties are discussed, providing insights into future studies of sophisticated structural descriptors to predict glass properties from composition and/or structure and aiding the formulation of borosilicate glasses for nuclear waste disposal and other applications.

The Heat Cycle Research Program, which is being conducted for the Department of Energy, has as its objective the development of the technology for effecting improved utilization of moderate temperature geothermal resources. Testing at the Heat Cycle Research Facility which was located at the DOE Geothermal Test Facility, East Mesa, California is presently being conducted to meet this objective. The testing effort discussed in this interim report involves a supercritical vaporization and counterflow in-tube condensing system with a near horizontal tube orientation. A previous report explored the supercritical heating, supersaturated turbine expansions and the condenser performance in the vertical orientation. This report presents a description of the test facility and results from a part of the program in which the condenser was oriented in a nearly horizontal orientation. Results of the experiments for the in-tube condenser in a nearly horizontal orientation are given for both pure and mixed-hydrocarbon working fluids. Although most of the data is for a completely active condenser in countercurrent flow, some data is available for a configuration in which half of the tubes were plugged and some data for cocurrent (parallel) flow is analyzed. The horizontal-oriented condenser behavior predicted by the Heat Transfer Research Institute computermore » codes used for correlation of the data was not in agreement with experimental results at this orientation. Some reasons for this difference are discussed. A special series of tests, conducted with propane and up to approximately 40% isopentane concentration, indicated that a close approach to integral'' condensation has occurred as was the case with the horizontally oriented condenser (similar results were obtained for the vertical condenser). 18 refs., 37 figs., 15 tabs.« less

Spherical cermet fuel elements are proposed for use in the Atoms For Peace Reactor (AFPR-100) concept. AFPR-100 is a small-scale, inherently safe, proliferation-resistant reactor that would be ideal for deployment to nations with emerging economies that decide to select nuclear power for the generation of carbon-free electricity. The basic concept of the AFPR core is a water-cooled fixed particle bed, randomly packed with spherical fuel elements. The flow of coolant within the particle bed is at such a low rate that the bed does not fluidize. This report summarizes an approach to fuel fabrication, results associated with fuel performance modeling, core neutronics and thermal hydraulics analyses demonstrating a ~20 year core life, and a conclusion that the proliferation resistance of the AFPR reactor concept is high.

The overall objective of this proposed research program is to determine the combustion characteristics of the blend derived from mixing a plant coal and recovered and clean coal fines from the pond. During this study, one plant coal and three blend samples will be prepared and utilized. The blend samples will be of a mixture of 90% plant coal + 10% fines, 85% plant coal + 15% fines, 80% plant coal + 20% fines having particle size distribution of 70% passing through -200 mesh size. These samples` combustion behavior will be examined in two different furnaces at Penn State University, i.e., a down-fired furnace and a drop-tube furnace. The down-fired furnace will be used mainly to measure the emissions and ash deposition study, while the drop tube furnace will be used to determine burning profile, combustion efficiency, etc.

A research project was conducted to investigate an experimental technique for measuring the rate of formation of mineral scale and corrosion in geothermal systems. A literature review was performed first to identify and evaluate available techniques for measuring scale in heat transfer equipment. As a result of these evaluations, a conceptual design was proposed for a geothermal Scaling Rate Meter (SRM) that would combine features of certain techniques used (or proposed for use) in other applications. An analysis was performed to predict the steady-state performance and expected experimental uncertainty of the proposed SRM. Sample computations were then performed to illustrate the system performance for conditions typical of a geothermal scaling application. Based on these results, recommendations are made regarding prototype SRM construction and testing.