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As integration of variable generation continues to grow rapidly in power systems globally, system planners are seeking new tools to understand the role of variable output generators and the challenges experienced with their integration. The North American Electric Reliability Corporation (NERC) has established a task force to examine the integration of variable generation. This paper details the achievements to date and outlines ongoing efforts from Task 1.2 on the capacity value of variable generation and from Task 1.4 on the concept of flexibility in power systems and options for its definition. Arising from international collaboration with the International Energy Agency, a discussion on the definition of flexible resources is presented. A potential metric for flexibility offered by conventional plant is developed and applied to a test system.

The growth of wind power as an electrical power generation resource has produced great benefits with reductions in emissions and the supply of zero cost fuel. It also has created challenges for the operation of power systems arising from the increased variability and uncertainty it has introduced. A number of studies have been performed over the past decade to analyze the operational impacts that can occur at high penetrations of wind. One of the most crucial impacts is the amount of incremental operating reserves required due to the variability and uncertainty of wind generation. This paper describes different assumptions and methods utilized to calculate the amount of different types of reserves carried, and how these methods have evolved as more studies have been performed.

This paper will summarize results from a number of utility wind integration case studies conducted recently in the US, and outline a number of mitigation measures based on insights from those studies.

We describe the cryostat and supporting electronics for the EBEX experiment. EBEX is a balloon-borne polarimeter designed to measure the B-mode polarization of the cosmic microwave background radiation. The instrument includes a 1.5 meter Gregorian-type telescope and 1432 bolometric transition edge sensor detectors operating at 0.3 K. Electronics for monitoring temperatures and controlling cryostat refrigerators is read out over CANbus. A timing system ensures the data from all subsystems is accurately synchronized. EBEX completed an engineering test flight in June 2009 during which the cryogenics and supporting electronics performed according to predictions. The temperatures of the cryostat were stable, and an analysis of a subset of the data finds no scan synchronous signal in the cryostat temperatures. Preparations are underway for an Antarctic flight., Comment: 11 pages, 6 figures, Proceedings of the 12th Marcel Grossman Conference

Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as intermittent) output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction of its energy from these sources as well as the cost of reliably integrating large amounts of variable generation into the electric grid. In this report, we explore the role of energy storage in the electricity grid, focusing on the effects of large-scale deployment of variable renewable sources (primarily wind and solar energy).

This paper discusses key results that had emerged at the time from two studies, the Western Wind and Solar Integration Study (covers the footprint of WestConnect, a group of transmission owners that covers most of Colorado, New Mexico, Arizona, Nevada, and Wyoming) and the Eastern Wind Integration and Transmission Study (covers a large part of the Eastern Interconnection). Results from both studies showed that high wind penetrations could be successfully integrated into the power system, but were dependant on sufficient transmission and significant changes in operations.

Paper examines the capacity requirements that arise as wind generation is integrated into the power system and how those requirements change depending on where the wind energy is delivered.

This paper attempts to evaluate which balancing area (BA) characteristics best accommodate wind energy.

The rapid growth of wind power as a generation resource in the past decade has given many utilities and Regional Transmission Organizations (RTO) concerns due to its unconventional characteristics. Because of these concerns, many of these entities have initiated studies that evaluate the feasibility of large amounts of wind power onto their system and the operational impacts present. This paper will discuss some of the past major studies, mostly focusing on the United States, and the basic methodologies that were used during these studies. The paper will also review many of the different results and conclusions of the studies and discuss how they have helped the power industry as a whole. Lastly, the authors will attempt to share their ideas on some of the limitations of the current and past integration studies, and some insight on how these may be evolving in the future.

Accurately calculating integration costs is important so that wind generation can be fairly compared with alternative generation technologies.

How did the universe evolve? The fine angular scale (l>1000) temperature and polarization anisotropies in the CMB are a Rosetta stone for understanding the evolution of the universe. Through detailed measurements one may address everything from the physics of the birth of the universe to the history of star formation and the process by which galaxies formed. One may in addition track the evolution of the dark energy and discover the net neutrino mass. We are at the dawn of a new era in which hundreds of square degrees of sky can be mapped with arcminute resolution and sensitivities measured in microKelvin. Acquiring these data requires the use of special purpose telescopes such as the Atacama Cosmology Telescope (ACT), located in Chile, and the South Pole Telescope (SPT). These new telescopes are outfitted with a new generation of custom mm-wave kilo-pixel arrays. Additional instruments are in the planning stages., Science White Paper submitted to the US Astro2010 Decadal Survey. Full list of 177 author available at http://cmbpol.uchicago.edu

The natural variability of wind power makes it different from other generating technologies, which can give rise to questions about how wind power can be integrated into the grid successfully. This article aims to answer several important questions that can be raised with regard to wind power. Although wind is a variable resource, grid operators have experience with managing variability that comes from handling the variability of load. As a result, in many instances the power system is equipped to handle variability. Wind power is not expensive to integrate, nor does it require dedicated backup generation or storage. Developments in tools such as wind forecasting also aid in integrating wind power. Integrating wind can be aided by enlarging balancing areas and moving to subhourly scheduling, which enable grid operators to access a deeper stack of generating resources and take advantage of the smoothing of wind output due to geographic diversity. Continued improvements in new conventional-generation technologies and the emergence of demand response, smart grids, and new technologies such as plug-in hybrids will also help with wind integration.

The objective of this paper is to provide an analysis and comparison of recent studies on the capacity credit of wind in the United States. We offer suggestions and recommendations for future studies, based on the recent work. We examine key wind capacity studies in the United States, emphasizing those done in the past three years.

The E and B Experiment, EBEX, is a Cosmic Microwave Background polarization experiment designed to detect or set upper limits on the signature of primordial gravity waves. Primordial gravity waves are predicted to be produced by inflation, and a measurement of the power spectrum of these gravity waves is a measurement of the energy scale of inflation. EBEX has sufficient sensitivity to detect or set an upper limit at 95% confidence on the energy scale of inflation of < 1.4 × 10^(16) GeV. This article reviews our strategy for achieving our science goals and discusses the implementation of the instrument.

Power systems must have enough generation to meet demand at each moment of the day. In addition, they must also have enough reserve to deal with unexpected contingencies. The increase in the penetration of wind generation in recent years has led to a number of challenges in the calculations required to facilitate wind generation while maintaining the existing level of security of supply. A key calculation in this process is the capacity credit or value of wind generation. Capacity credit/value of wind generation can be broadly defined as the amount of firm conventional generation capacity that can be replaced with wind generation capacity, while maintaining the existing levels of security of supply. This topic has been the subject of much study and debate in recent times. The aim of this paper is to give an overview of the state of the art in this area, in particular with regard to the work of IEA WIND Task 25 and the work detailed in its state of the art report on the design and operation of power systems with large amounts of wind power.

This paper uses NREL's newest Jobs and Economic Development Impacts (JEDI II) model to assess economic impacts from alternative power technologies, with a focus on wind energy, for a variety of states.

This report--the first in what is envisioned to be an ongoing annual series--attempts to fill this need by providing a detailed overview of developments and trends in the U.S. wind power market, with a particular focus on 2006.

EBEX is a balloon-borne polarimeter designed to measure the intensity and polarization of the cosmic microwave background radiation. The measurements would probe the inflationary epoch that took place shortly after the big bang and would significantly improve constraints on the values of several cosmological parameters. EBEX is unique in its broad frequency coverage and in its ability to provide critical information about the level of polarized Galactic foregrounds which will be necessary for all future CMB polarization experiments. EBEX consists of a 1.5 m Dragone-type telescope that provides a resolution of less than 8 arcminutes over four focal planes each of 4 degree diffraction limited field of view at frequencies up to 450 GHz. The experiment is designed to accommodate 330 transition edge bolometric detectors per focal plane, for a total of up to 1320 detectors. EBEX will operate with frequency bands centered at 150, 250, 350, and 450 GHz. Polarimetry is achieved with a rotating achromatic half-wave plate. EBEX is currently in the design and construction phase, and first light is scheduled for 2008., Comment: 13 pages, 10 figures. Figure 1 is changed from the one which appeared in the Proceedings of the SPIE

Technical & operational integrity issues and their resolutions are dealt with leading to the concept selection for a high H2S (33% H2S) gas development in Abu Dhabi. Two strategic principles underpinned the concept selection and field development plan: (1) minimise Health, Safety and Environment (HSE) risks and (2) employ field proven technology and practices as far as practicable. Sulphur production instead of acid gas injection was rejected as a viable development option due to its environmental impact and the poor prospects for sulphur marketing. Developmental technical issues included sulphur precipitation in the production tubing and pipelines, and material selection for the sour gas well completions and the gathering & injection pipelines. Materials selection was based on designing out all catastrophic failures and corrosion mitigation & monitoring of progressive corrosion failure mechanisms. Operational issues were related to minimal facility manning and competence assurance of sour gas operatives.

The National Renewable Energy Laboratory (NREL) started a project in 2000 to record long-term, high-frequency (1-Hz) wind power output data from large commercial wind power plants. Outputs from about 330 MW of wind generating capacity from wind power plants in Buffalo Ridge, Minnesota, and Storm Lake, Iowa, are being recorded. Analysis of the collected data shows that although very short-term wind power fluctuations are stochastic, the persistent nature of wind and the large number of turbines in a wind power plant tend to limit the magnitudes and rates of changes in the levels of wind power. Analyses of power data confirm that spatial separation greatly reduces variations in the combined wind power output relative to output from a single wind power plant. Data show that high frequency variations of wind power from two wind power plants 200 km apart are independent of each other, but low frequency power changes can be highly correlated. This fact suggests that time-synchronized power data and meteorological data can aid in the development of statistical models for wind power forecasting.

OAK-B135 The primary objective of this study is to provide examples of thorough and consistent analysis and documentation of economic impacts from wind power development.

This paper summarizes a number of projects undertaken at the National Renewable Energy Laboratory (NREL) that focus on the analysis and modeling of large-scale wind generation. The findings indicate that wind power plants can provide significant economic benefits to the generating system. Potential problems caused by the intermittency of a wind plant can be significantly reduced by accurate wind forecasting, geographic dispersion of turbines within a plant, as well as disperse wind-generating facilities. Wind plants do not require significant backup facilities because risk-analysis techniques assess the risk of system failure on a system-wide basis.

Air samples were collected simultaneously at three sites downwind of Lake Ontario and at a control site near Lake Erie from March to July of 1999. The Lake Erie site (Stockton, NY) had PCB concentrations similar to rural Integrated Atmospheric Deposition Network (IADN) sampling sites across the Great Lakes, exhibited limited seasonal variation, and approximates regional background. Samples taken along Lake Ontario's southeastern shore (Rice Creek and Sterling, NY) had elevated PCB concentrations averaging approximately 1 ng/m3 and were more chlorinated than air collected at IADN sites and at Stockton. Air samples from Potsdam (approximately 75 km inland) had similar concentrations but were less chlorinated. Clausius-Clapeyron plots revealed a strong correlation between PCB fugacity and temperature near Lake Ontario; however, the extent of chlorination of the air samples rules out volatilization from the lake as a major source. It is hypothesized that volatilization from local surfaces, enriched in higher chlorinated congeners by meteorological or geographic factors, drives both the concentration and composition of airborne PCBs along Lake Ontario's southeastern shore.

Although it is widely recognized that variations in annual wind energy capture can be significant, it is not clear how significant this effect is on accurately calculating the capacity credit of a wind plant. An important question is raised concerning whether one year of wind data is representative of long-term patters. This report calculates the range of capacity credit measures based on 13 years of actual wind-speed data. The results are compared to those obtained with synthetic data sets that are based on one year of data. Although the use of synthetic data sets is a considerable improvement over single-estimate techniques, this report finds that the actual inter-annual variation in capacity credit is still understated by the synthetic data technique.

Electric utility planners and wind energy researchers pose a common question: What is the capacity value of a wind plant? Tentative answers, which can be phrased in a variety of ways, are based on widely varying definitions and methods of calculation. From the utility`s point of view, a resource that has no capacity value also has a reduced economic value. Utility planners must be able to quantify the capacity value of a wind plant so that investment in conventional generating capacity can be potentially offset by the capacity value of the wind plant. Utility operations personnel must schedule its conventional resources to ensure adequate generation to meet load. Given a choice between two resources, one that can be counted on and the other that can`t, the utility will avoid the risky resource. This choice will be reflected in the price that the utility will pay for the capacity: higher capacity credits result in higher payments. This issue is therefore also important to the other side of the power purchase transaction -- the wind plant developer. Both the utility and the developer must accurately assess the capacity value of wind. This article summarizes and evaluates some common methods of evaluating capacity credit. During the new era of utility deregulation in the United States, it is clear that many changes will occur in both utility planning and operations. However, it is my judgement that the evaluation of capacity credit for wind plants will continue to play an important part in renewable energy development in the future.

We compare the geometric and physical-optics performance of two configurations of offset dual-reflector antennas that obey the Mizuguchi-Dragone condition. The traditional Gregorian configuration is compared with the larger crossed configuration. These configurations are candidates for experiments that measure the polarization of the cosmic microwave background. Particular attention is given to wide-field performance and polarization fidelity. Both a ray tracer and a physical optics simulation package are used to conclude that the crossed configuration has a larger diffraction-limited field of view, but within this limit both configurations have roughly the same instrumental polarization and both show excellent cross-polarization levels, with the crossed configuration showing approximately 10 dB better performance.

Wind power plant output depends on wind speed. Such speeds cannot be accurately predicted over daily periods because the wind fluctuates from minute-to-minute and hour-to-hour. Consequently, electric utility system planners and operators are concerned that variations in wind plant output may increase the operating costs of the system. This concern arises because the system must maintain balance between the aggregate demand for electric power and the total power generated by all power plants feeding the system. The operators' concerns are compounded because unlike conventional power plants that are generally under their control and thus are dispatchable, the wind plants are controlled by nature. It should be understood that the key issue is not whether a system with a significant amount of wind capacity can be operated reliably, but rather to what extent the system operating costs are increased by the variability of the wind.

REPORT OF A CASE A 43-year-old woman presented with skin lesions of 1 year's duration. Two years earlier, an adenoma of the thyroid gland and a carcinoma of the left breast were removed surgically. She denied a family history of neoplasms of the breast or thyroid gland but said that her sister had growths similar to hers on the face and that her 13-year-old daughter had warty growths on her fingers. Her skin examination revealed sessile and conical (Figure 1) 2- to 3-mm papules scattered over the face, an oval white plaque on the left buccal mucosa (Figure 2), two circumscribed areas of hyperkeratosis on the terminal phalanx of the right thumb (Figure 3), and what appeared to be typical plantar warts. Her daughter had a similar hyperkeratotic papule on an index finger and on the lateral aspect of her right hand. Biopsy specimens were taken from one of the

Sixty undergraduate males delivered electric shocks to a confederate as punishment for making errors on a learning task. Half did so after being exposed to an aggressive model, whereas the other half did so without being exposed. Shocks were delivered from a room whose atmosphere was either unpolluted or contaminated by a moderately unpleasant odor (ethyl mercoptan) or an extremely obnoxious stench (ammonium sulfide). As hypothesized, the moderately unpleasant pollutant facilitated higher levels of aggression than either the extremely obnoxious one or the absence of pollution. However, contrary to a second hypothesis, pollution facilitated aggression only in the model's absence. The confirmation of the first hypothesis was interpreted as supporting and extending the affect-aggression model from heat research. It was speculated that disconfirmation of the second hypothesis resulted either from a ceiling effect or from malodor distracting attention away from the aggressive cues of the model. The methodological, theoretical, and applied implications of research on air pollution were discussed.

Wind power forecasting is essential for greater penetration of wind power into electricity systems. Because no wind forecasting system is perfect, a thorough understanding of the errors that may occur is a critical factor for system operation functions, such as the setting of operating reserve levels. This paper provides an international comparison of the distribution of wind power forecasting errors from operational systems, based on real forecast data. The paper concludes with an assessment of similarities and differences between the errors observed in different locations.

Variability of large scale wind power generation is dependent on several factors: characteristics of installed wind power plants, size of the area where the plants are installed, geographic dispersion within that area and its weather regime(s). Variability can be described by ramps in power generation, i.e. changes from time period to time period. Given enough data points, it can be described with a probability density function. This approach focuses on two dimensions of variability: duration of the ramp and probability distribution. This paper proposes an index based on these two dimensions to enable comparisons and characterizations of variability under different conditions. The index is tested with real, large scale wind power generation data from several countries. Considerations while forming an index are discussed, as well as the main results regarding what the drivers of variability experienced for different data.

The E and B Experiment (EBEX) is a balloon-borne polarimeter designed to measure the polarization of the cosmic microwave background radiation and to characterize the polarization of galactic dust. EBEX was launched December 29, 2012 and circumnavigated Antarctica observing $\sim$6,000 square degrees of sky during 11 days at three frequency bands centered around 150, 250 and 410 GHz. EBEX was the first experiment to operate a kilo-pixel array of transition-edge sensor bolometers and a continuously rotating achromatic half-wave plate aboard a balloon platform. It also pioneered the use of detector readout based on digital frequency domain multiplexing. We describe the temperature calibration of the experiment. The gain response of the experiment is calibrated using a two-step iterative process. We use signals measured on passes across the Galactic plane to convert from readout-system counts to power. The effective smoothing scale of the EBEX optics and the star camera-to-detector offset angles are determined through \c{hi}2 minimization using the compact HII region RCW 38. This two-step process is initially performed with parameters measured before the EBEX 2013 flight and then repeated until the calibration factor and parameters converge., 6 pages, 3 figures, Proceedings of the 14th Marcel Grossman Conference