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Global warming has drawn great attention in recent years because of its large impact on many aspects of the environment and human activities in buildings. One area directly affected by climate change is the energy consumption for heating and cooling. To quantify the impact, this study used the HadCM3 Global Circulation Model (GCM) to generate weather data for future typical meteorological years, such as 2020, 2050, and 2080, for 15 cities in the U.S. based on three CO 2 emission scenarios. The method was validated by comparing the projected TMY3 data using HadCM3 with the actual TMY3 data. By morphing method, the weather data was downscaled to hourly data for use in building energy simulations by EnergyPlus. Two types of residential buildings and seven types of commercial buildings were simulated for each of the 15 cities. This paper is the first to systematically study the climate change impact on various types of residential and commercial buildings in all seven climate zones in the U.S. through EnergyPlus simulations and provide weighted averaged results for national-wide building stock. We also identified geographical dependency of the impact of climate change on future energy uses. There would be a net increase in source energy consumption by the 2080s for climate zones 1–4 and net decrease in climate zones 6–7 based on the HadCM3 weather projection. Furthermore, this paper investigated natural ventilation performance in San Francisco, San Diego, and Seattle with improved natural ventilation model. We found that by the 2080s passive cooling would not be suitable for San Diego because of global warming, but it would still be acceptable for San Francisco and Seattle. [ABSTRACT FROM AUTHOR]

Recent national focus on the value of increasing US supplies of indigenous renewable energy underscores the need for re-evaluating all alternatives, particularly those that are large and well distributed nationally. A panel was assembled in September 2005 to evaluate the technical and economic feasibility of geothermal becoming a major supplier of primary energy for US base-load generation capacity by 2050. Primary energy produced from both conventional hydrothermal and enhanced (or engineered) geothermal systems (EGS) was considered on a national scale. This paper summarizes the work of the panel which appears in complete form in a 2006 MIT report, 'The future of geothermal energy' parts 1 and 2. In the analysis, a comprehensive national assessment of US geothermal resources, evaluation of drilling and reservoir technologies and economic modelling was carried out. The methodologies employed to estimate geologic heat flow for a range of geothermal resources were utilized to provide detailed quantitative projections of the EGS resource base for the USA. Thirty years of field testing worldwide was evaluated to identify the remaining technology needs with respect to drilling and completing wells, stimulating EGS reservoirs and converting geothermal heat to electricity in surface power and energy recovery systems. Economic modelling was used to develop long-term projections of EGS in the USA for supplying electricity and thermal energy. Sensitivities to capital costs for drilling, stimulation and power plant construction, and financial factors, learning curve estimates, and uncertainties and risks were considered.

This paper discusses the full-power testing of a 36.5 MW High Temperature Superconductor (HTS) propulsion motor at the Navy's Land Based Test Site (LBTS) located in Philadelphia, PA. This motor was developed under funding from the Office of Naval Research and passed no-load factory testing at Philadelphia in March 2007. The Naval Surface Warfare Center (Carderock Division - Philadelphia site) designed and installed a test facility at LBTS to support full-power/full-torque testing of the HTS motor delivered to the Navy in 2007. The facility, test plan and full-power and full-torque test results of the HTS propulsion motor are presented. These test results provide the final substantiation that this technology is ready for integration in to a Navy electric drive combatant. [ABSTRACT FROM AUTHOR]

Abstract: Optimization of combined cooling, heating, and power (CCHP) systems operation commonly focuses only on energy cost. Different algorithms have been developed to attain optimal utilization of CCHP units by minimizing the energy cost in CCHP systems operation. However, other outcomes resulting from CCHP operation such as primary energy consumption and emission of pollutants should also be considered during CCHP systems evaluation as one would expect these outcomes can be subject to regulation. This paper presents an optimization of the operation of CCHP systems for different climate conditions based on operational cost, primary energy consumption (PEC), and carbon dioxide emissions (CDE) using an optimal energy dispatch algorithm. The results for the selected cities demonstrate that in general there is not a common trend among the three optimization modes presented in this paper since optimizing one parameter may reduce or increase the other two parameters. The only cities that show reduction of PEC while also reducing the CDE are Columbus, MS; Minneapolis, MN; and Miami, FL. For these cities the operational cost always increases when compared to the reference case consisting of using a vapor/compression cycle for cooling and natural gas for heating. On the other hand, for San Francisco and Boston, CCHP systems increase the CDE. In general, if CCHP systems increase the cost of operation, as long as energy savings and reduction of emissions are guaranteed, the implementation of these systems should be considered. [Copyright &y& Elsevier]

This paper aims to analyse: (a) how the attitude towards renewable energy-based heating systems, pro-environmental behaviour and the perceived attributes of technology influence intention to convert residential heating systems from fossil fuels to biofuels, and (b) the moderating role of culture based on Hofstede's individualism dimension. A total of 425 responses were collected from a panel of internet users from representative countries in three continents (the United States, the United Kingdom and South Africa); the data analysis was carried out using structural equation models in a multigroup analysis. The results showed that attitude towards renewable energy-based heating systems is influenced by environmental variables in the United States and the United Kingdom, and by the perceived attributes of clean residential heating systems in the United States and South Africa. Attitude, in turn, impacts on the intention to convert from fossil fuels to biofuels. In addition, individualism has a moderating effect between these variables and there are intercultural differences in the degree of importance attributed to them. The study concludes the use of these energy systems as drivers of environmentally-sustainable development. [ABSTRACT FROM AUTHOR]

This paper aims to quantify the performance of Model Predictive Control (MPC) for a typical commercial building heating, ventilation and air conditioning (HVAC) system across a wide range of climate and weather conditions. The motivation of the study comes from the fact that although there is a large body of work on MPC for HVAC systems, there is a lack of studies that examine the range of possible performance of MPC, in terms of both energy savings and maintaining indoor climate (temperature and humidity) as a function of outdoor weather. A challenge in conducting such a study is developing an MPC controller that can be used in a wide range of weather. The root cause of this challenge is the need for a tractable cooling and dehumidification coil model that can be used by the MPC controller, since the coil may operate in quite distinct modes depending on weather. We present such an MPC controller, and then leverage it to conduct an extensive simulation campaign for fourteen climate zones in the United States and four weather conditions (winter, spring, summer, and fall) in each climate zone. The performance of the proposed controller is compared with not only a rule-based baseline controller but also with a simpler MPC controller that ignores humidity and latent heat considerations. There are several results the arise from this comparative study. One such result is that energy savings from MPC over baseline can vary dramatically based on climate and season. Another is that the effect of ignoring humidity in the MPC formulation can lead to poor indoor humidity control more in milder weather rather than in hot weather. The results from this study can help practitioners and researchers assess costs and benefits of proposed MPC formulations for HVAC control. • Performance of two MPC controllers for HVAC systems is studied. • The study spans a wide range of climate and weather conditions, a first of its kind. • MPC controller can perform poorly unless latent heat is considered in design. • Poor performance occurs typically in moist and marine climate zones. [ABSTRACT FROM AUTHOR]

Abstract: This paper identifies the impact of thermostat strategies on heating and cooling energy consumptions in buildings, thus suggesting the importance of a database for understanding the effect of thermostat settings and for deciding energy-conscious strategies. Using computer simulation, diverse thermostat strategies – change of setback period, change of set-point temperature, and change of setback temperature – were tested parametrically in a typical USA single-family homes, located in two climate zones, namely cold (Detroit, Michigan) and hot-humid (Miami, Florida). Analysis revealed that heating and cooling systems were significant energy-consuming components in each climate zone. Accordingly, heating energy in cold climate zones and cooling energy in hot-humid climate zones have potential for matchingly significant saving. Diverse thermostat strategies (changes of setback period, of set-point, of setback temperature) demonstrated their obvious impacts on such saving. In the cold climate in particular, the heating system showed the most significant energy-saving effect via proper thermostat strategies. Proper setback period, set-point and setback temperature need to be established to achieve energy efficiency in residential buildings. [ABSTRACT FROM AUTHOR]

Exposure to noise—or unwanted sound—is considered a major public health issue in the United States and internationally. Previous work has shown that even acute noise exposure can influence physiological response in humans and that individuals differ markedly in their susceptibility to noise. Recent research also suggests that specific acoustic properties of noise may have distinct effects on human physiological response. Much of the existing research on physiological response to noise consists of laboratory studies using very simple acoustic stimuli—like white noise or tone bursts—or field studies of longer-term workplace noise exposure that may neglect acoustic properties of the noise entirely. By using laboratory exposure to realistic heating, ventilation, and air conditioning (HVAC) noise, the current study explores the interaction between acoustic properties of annoying noise and individual response to working in occupational noise. This study assessed autonomic response to two acoustically distinct noises while participants performed cognitively demanding work. Results showed that the two HVAC noises affected physiological arousal in different ways. Individual differences in physiological response to noise as a function of noise sensitivity were also observed. Further research is necessary to link specific acoustic characteristics with differential physiological responses in humans. [ABSTRACT FROM AUTHOR]

• Article analyzes reported thermostat settings by 494 males and 786 females living in the US. • Average male and female reported thermostat settings differ by no more than 0.3 °C [0.5 °F]. • Controlling for demographic and environmental characteristics reduces the difference. This paper examines the extent to which males and females report different thermostat settings using data from single-occupant homes in the United States. Reported thermostat settings for heating and cooling at night, at home, and when away from home are rigorously tested for behavioral differences between the sexes. In general, single-occupant males and females report the same thermostat settings on average. The lack of differences between sexes is robust to controlling for demographic characteristics and environmental variables that differ systematically between the samples using both regression and decomposition approaches. These findings have important implications for thermostat settings and thermal comfort in shared spaces. [ABSTRACT FROM AUTHOR]

The instruments for active spacecraft potential control to be launched with the NASA Magnetospheric Multiscale (MMS) mission in 2014 have recently been qualified, and the first two out of a total of eight flight models have completed their acceptance test campaign. At the heart of these instruments are liquid metal ion sources with indium, developed at Forschungsund Technologietransfer GmbH. Earlier versions have been flown in the Equator-S, Cluster, and Double Star missions. The redesign efforts to comply with the stringent requirements of the MMS mission are described in detail, as well as the qualification program for the emitters and the instruments. Starting with mechanical and thermal analyses and tests, continuing with performance and life testing, and finally by analysis of the overall performance in the mission application, it can be demonstrated that the new generation of ion emitters beats the performance of previous versions in all aspects. The description of verification efforts is completed by the results from tests at instrument level of the qualification model and the first flight models. [ABSTRACT FROM PUBLISHER]

We estimate the capacity value of concentrating solar power (CSP) plants with thermal energy storage (TES) in the southwestern U.S. Our results show that incorporating TES in CSP plants significantly increases their capacity value. While CSP plants without TES have capacity values ranging between 60% and 86% of maximum capacity, plants with TES can have capacity values between 79% and 92%. We demonstrate the effect of location and configuration on the operation and capacity value of CSP plants. We also show that using a capacity payment mechanism can increase the capacity value of CSP, since the capacity value of CSP is highly sensitive to operational decisions and energy prices are not a perfect indicator of scarcity of supply. [ABSTRACT FROM PUBLISHER]

A unified land model (ULM) is described that combines the surface flux parameterizations in the Noah land surface model (used in most of NOAA's coupled weather and climate models) with the Sacramento Soil Moisture Accounting model (Sac; used for hydrologic prediction within the National Weather Service). The motivation was to develop a model that has a history of strong hydrologic performance while having the ability to be run in the coupled land-atmosphere environment. ULM takes the vegetation, snow model, frozen soil, and evapotranspiration schemes from Noah and merges them with the soil moisture accounting scheme from Sac. ULM surface fluxes, soil moisture, and streamflow simulations were evaluated through comparisons with observations from the Ameriflux (surface flux), Illinois Climate Network (soil moisture), and Model Parameter Estimation Experiment (MOPEX; streamflow) datasets. Initially, a priori parameters from Sac and Noah were used, which resulted in ULM surface flux simulations that were comparable to those produced by Noah (Sac does not predict surface energy fluxes). ULM with the a priori parameters had streamflow simulation skill that was generally similar to Sac's, although it was slightly better (worse) for wetter (more arid) basins. ULM model performance using a set of parameters identified via a Monte Carlo search procedure lead to substantial improvements relative to the a priori parameters. A scheme for transfer of parameters from streamflow simulations to nearby flux and soil moisture measurement points was also evaluated; this approach did not yield conclusive improvements relative to the a priori parameters. [ABSTRACT FROM AUTHOR]

Data collected in the low-level atmospheric boundary layer in five hurricanes by NOAA research aircraft are analyzed to measure turbulence with scales small enough to retrieve the rate of dissipation. A total of 49 flux runs suitable for analysis are identified in the atmospheric boundary layer within 200 m above the sea surface. Momentum fluxes are directly determined using the eddy correlation method, and drag coefficients are also calculated. The dissipative heating is estimated using two different methods: 1) integrating the rate of dissipation in the surface layer and 2) multiplying the drag coefficient by the cube of surface wind speed. While the latter method has been widely used in theoretical models as well as several numerical models simulating hurricanes, these analyses show that using this method would significantly overestimate the magnitude of dissipative heating. Although the dataset used in this study is limited by the surface wind speed range <30 m s−1, this work highlights that it is crucial to understand the physical processes related to dissipative heating in the hurricane boundary layer for implementing it into hurricane models. [ABSTRACT FROM AUTHOR]

Simple Summary: The western corn rootworm is a highly adaptive pest that has evaded nearly all management tactics developed to date. Antibiotics have been utilized in rootworm diets to mitigate bacterial contamination. However, antibiotic ingestion necessarily alters rootworm gut microbiota, clouding the outcome of diet toxicity bioassays used in determination of rootworm susceptibility to insecticides. Rapid heating, or pasteurization, is one of the most widely applied techniques to alleviate microbial contamination and could eliminate antibiotics from the diet. We characterized effects of temperatures and time intervals of thermal exposure on quality of rootworm diet by measuring larval weight, molting, and survival. Our results demonstrated non-linear effects of thermal exposure on the performance of diet, whereas no impacts were observed on the exposure intervals evaluated. These findings will guide the continued development of sterilized rootworm diets, facilitating mass production and provide insights into the design of diets for other insects. The western corn rootworm (WCR), Diabrotica virgifera LeConte, is the most serious pest of maize in the United States. In pursuit of developing a diet free of antibiotics for WCR, we characterized effects of thermal exposure (50–141 °C) and length of exposure on quality of WCRMO-2 diet measured by life history parameters of larvae (weight, molting, and survival) reared on WCRMO-2 diet. Our results indicated that temperatures had non-linear effects on performance of WCRMO-2 diet, and no impacts were observed on the length of time exposure. The optimum temperature of diet processing was 60 °C for a duration less than 30 min. A significant decline in development was observed in larvae reared on WCRMO-2 diet pretreated above 75 °C. Exposing WCRMO-2 diet to high temperatures (110–141 °C) even if constrained for brief duration (0.9–2.3 s) caused 2-fold reduction in larval weight and significant delays in larval molting but no difference in survival for 10 days compared with the control diet prepared at 65 °C for 10 min. These findings provide insights into the effects of thermal exposure in insect diet processing. [ABSTRACT FROM AUTHOR]

Building-related symptoms in office workers worldwide are common, but of uncertain etiology. One cause may be contaminants related to characteristics of heating, ventilating, and air-conditioning (HVAC) systems. We analyzed data from 97 representative air-conditioned US office buildings in the Building Assessment and Survey Evaluation (BASE) study. Using logistic regression models with generalized estimating equations, we estimated odds ratios (OR) and 95% confidence intervals for associations between building-related symptom outcomes and HVAC characteristics. Outdoor air intakes less than 60 m above ground level were associated with significant increases in most symptoms: e.g. for upper respiratory symptoms, OR for intake heights 30 to 60 m, 0 to <30 m, and below ground level were 2.7, 2.0, and 2.1. Humidification systems with poor condition/maintenance were associated with significantly increased upper respiratory symptoms, eye symptoms, fatigue/difficulty concentrating, and skin symptoms, with OR = 1.5, 1.5, 1.7, and 1.6. Less frequent cleaning of cooling coils and drain pans was associated with significantly increased eye symptoms and headache, with OR = 1.7 and 1.6. Symptoms may be due to microbial exposures from poorly maintained ventilation systems and to greater levels of vehicular pollutants at air intakes nearer the ground level. Replication and explanation of these findings is needed. Practical Implications These findings support current beliefs that moisture-related HVAC components such as cooling coils and humidification systems, when poorly maintained, may be sources of contaminants that cause adverse health effects in occupants, even if we cannot yet identify or measure the causal exposures. While finding substantially elevated risks for poorly maintained humidification systems, relative to no humidification systems, the findings do not identify important (symptom) benefits from well-maintained humidification systems. Findings also provide an initial suggestion, needing corroboration, that outdoor air intakes lower than 18 stories in office buildings may be associated with substantial increases in many symptoms. If this is corroborated and linked to ground-level vehicle emissions, urban ventilation air intakes may need to be located as far above ground level as possible or to incorporate air cleaners that remove gaseous pollutants. [ABSTRACT FROM AUTHOR]

This article examines how the growth of northern urban centers in the U.S. coincided with the first major fuel crisis in American history. The author explores how firewood shortages impacted individuals living in the cities of Boston, Massachusetts, Philadelphia, Pennsylvania and New York City. Poor individuals living in these cities were impacted more severely by sudden increases in the price of firewood due to supply shortages. The author examines the efforts of several organizations that attempted to combat fuel shortages by urging U.S. citizens to adopt coal as a heating source. The author discusses how the fuel market provided information on the consumption patterns of Americans and also exposed class differences in the country.

We present an apatite fission-track (AFT) study of five plutonic rocks and seven metamorphic rocks across 310 km of the Yukon–Tanana Upland in east-central Alaska. Samples yielding ~40 Ma AFT ages and mean confined track lengths > 14 µm with low standard deviations cooled rapidly from >120°C to <50°C during a 3–5 Ma period, beginning at about 40 Ma. Data from samples yielding AFT ages >40 Ma suggest partial annealing and, therefore, lower maximum temperatures (~90–105°C). A few samples with single-grain ages of ~20 Ma apparently remained above ~50°C after initial cooling. Although the present geothermal gradient in the western Yukon–Tanana Upland is ~32°C/km, it could have been as high as 45°C/km during a widespread Eocene intraplate magmatic episode. Prior to rapid exhumation, samples with ~40 Ma AFT ages were >3.8–2.7 km deep and samples with >50 Ma AFT ages were >3.3–2.0 km deep. We calculate a 440–320 m/Ma minimum rate for exhumation of all samples during rapid cooling. Our AFT data, and data from rocks north of Fairbanks and from the Eielson deep test hole, indicate up to 3 km of post-40 Ma vertical displacement along known and inferred northeast-trending high-angle faults. The predominance of 40–50 Ma AFT ages throughout the Yukon–Tanana Upland indicates that, prior to the post-40 Ma relative uplift along some northeast-trending faults, rapid regional cooling and exhumation closely followed the Eocene extensional magmatism. We propose that Eocene magmatism and exhumation were somehow related to plate movements that produced regional-scale oroclinal rotation, northward translation of outboard terranes, major dextral strike-slip faulting, and subduction of an oceanic spreading ridge along the southern margin of Alaska.Nous présentons une étude de datation de l'apatite par la méthode des traces de fission (AFT) pour cinq roches plutoniques et sept roches métamorphiques prélevées sur 310 km des hautes terres du Yukon–Tanana dans le centre-est de l'Alaska. Présentant des âges ~40 Ma AFT et des traces confinées de longueur moyenne > 14 microns avec de faibles écarts types, les échantillons ont refroidi rapidement de > 120 1C à < 50 1C au cours d'une période de 3–5 Ma, débutant il y a environ 40 Ma. Les données provenant d'échantillons donnant des âges AFT > 40 Ma suggèrent un recuit partiel et, par conséquent, des températures maximum inférieures (~ 90 à 105 1C). Quelques échantillons présentant des âges de ~ 20 Ma, déterminés sur un seul grain, seraient demeurées à des températures supérieures à ~ 50 1C après le refroidissement initial. Bien que le gradient géothermique actuel dans l'ouest des hautes terres du Yukon–Tanana soit de ~32 1C/km, il aurait pu atteindre 45 1C/km durant un vaste épisode magmatique intra-plaque, à l'Éocène. Avant une exhumation rapide, des échantillons dont les âges AFT étaient ~ 40 Ma se trouvaient à des profondeurs de 3,8–2,7 km et les échantillons dont les âges AFT étaient > 50 Ma se trouvaient à des profondeurs > 3,3–2,0 km. Nous calculons un taux minimum de 440–320 m/Ma pour l'exhumation de tous les échantillons durant un refroidissement rapide. Nos données AFT et des données provenant de roches au nord de Fairbanks et du forage d'essai profond Eielson indiquent jusqu'à 3 km de déplacement vertical post-40 Ma, le long de failles connues et inférées à tendance nord-est et à angle élevé. La prédominance d'âges AFT de 40–50 Ma à travers toutes les hautes terres du Yukon–Tanana indique qu'avant le soulèvement relatif post-40 Ma, le long de quelques failles à direction nord-est, un refroidissement régional rapide et l'exhumation ont suivi de près le magmatisme de distension à l'Éocène. Nous proposons que le magnétisme et l'exhumation à l'Éocène étaient reliés d'une façon quelconque aux mouvements de plaques qui ont produit une rotation oroclinale d'échelle régionale, une translation de terranes extérieurs vers le nord, de grandes failles à rejet horizontal dextre et la subduction d'une crête d'étalement océanique le long de la bordure sud de l'Alaska.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Members of the Mycobacterium avium complex (MAC) are waterborne, opportunistic pathogens whose characteristics make urban water distribution systems and household plumbing ideal habitats for their survival, persistence and growth. Rather than contaminants, MAC are colonists of drinking water systems. MAC are normal inhabitants of natural soils and water, and enter drinking water treatment systems through surface sources. A proportion of MAC survive transmission through the treatment plant, and regrow in the distribution system and household plumbing. Once within household plumbing, MAC adhere to surfaces and form biofilms, thus preventing their washout. The thermal tolerance of MAC leads to growth in water heating systems. Stagnation does not reduce MAC numbers, as MAC can grow at low oxygen levels. MAC present challenges to current water monitoring approaches as their numbers do not correlate with E. coli, fecal coliforms or heterotrophic plate count bacteria. [ABSTRACT FROM AUTHOR]