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Energy provides safety, comfort and mobility to people, and is essential for industrial, commercial and societal growth. However, generation and consumption of energy give rise of greenhouse gases and various air pollutants, which have a negative impact on the natural environment and global climate. The building sector is responsible for about 40% of the energy consumption and related CO 2 emissions worldwide. In order to reduce the environmental impact of buildings, energy efficient measures must be taken into account when designing, operating and retrofitting buildings. It is imperative that holistic consideration is given to the structural, environmental and energy aspects in buildings through their life. In order to maintain safe, healthy and comfortable sustainable buildings, assurance of the structural and environmental building performance must be given not only at the design, but also commissioning and operation stages of its life cycle. This paper presents the motivation, objectives and method description of the measurement framework developed at the National University of Ireland Galway in order to continuously monitor the structural and environmental performance of operating buildings. The proposed real-time monitoring provides rich information about the building performance, offering opportunities for better control strategies for operating buildings. This may lead to safer, healthier, more comfortable and productive indoor environments, at the same time ensuring the reduced/optimised energy consumption in buildings. [ABSTRACT FROM AUTHOR]

For certain temperate climate types, cooling towers have the potential to produce high temperature chilled water, which when used in conjunction with radiant and displacement cooling technologies, have prompted interest in this concept as a potential approach for the conditioning of buildings. The feasibility of the proposed system depends largely, on achieving low approach water temperatures within an appropriately designed cooling tower, at acceptable levels of energy performance. Using a validated mathematical model, the current paper examines the performance of such a cooling tower for four different temperate climate conditions. The current assessment shows for building water return temperature of 22 °C, for temperate climates that are considered warm and humid, the limitations on cooling tower operation are when ambient conditions exceed 25 °C and 75% RH. Two strategies were investigated to allow the smallest practicable approach to the wet bulb temperature to be achieved: (i) increasing the tower air flowrate, (ii) decreasing the tower water flowrate. For a temperate climate that is warm and humid, operating the cooling tower with an approach of 1.0 K was found to be not practicable for all encountered weather conditions, but use of a 2.0 K approach was found to be practicable for all conditions. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents annual experimental performance of pyramid shaped skylight for daylighting of a dome shaped adobe house located at solar energy park in New Delhi (India). This approach of single story dome shaped building with skylight is more useful for rural and semi-urban sectors for both office and residential buildings reducing artificial lighting energy consumption. The hourly measured data of inside and outside illuminance for three different working surface levels inside the existing rooms are presented for each month of the year. The embodied energy payback time of the skylight is also determined on the basis of lighting energy saving potential. [Copyright &y& Elsevier]

Abstract: Pavement of the surfaces, along with a possible climate change induced increase of rainfall intensities, is one of key factors accountable for (increased) flooding in urban areas. Consequently higher runoffs have an impact on sewer system performance in terms of higher risk of flooding and decrease of storm water treatment performance. This paper presents a sensitivity analysis to compare impact of increased rainfall intensities and pavement of urban areas. It can be seen that both impacts result in a similar figure. Hence it is important to look into both aspects when trying to predict future performance of combined sewer systems. [Copyright &y& Elsevier]

Abstract: Nature-inspired metaheuristics found various applications in different fields of science, including the problem of artificial neural networks (ANN) training. However, very versatile opinions regarding the performance of metaheuristics applied to ANN training may be found in the literature. Both nature-inspired metaheuristics and ANNs are widely applied to various geophysical and environmental problems. Among them the water temperature forecasting in a natural river, especially in colder climate zones where the seasonality plays important role, is of great importance, as water temperature has strong impact on aquatic life and chemistry. As the impact of possible future climate change on water temperature is not trivial, models are needed to allow projection of streamwater temperature based on simple hydro-meteorological variables. In this paper the detailed comparison of the performance of nature-inspired optimization methods and Levenberg–Marquardt (LM) algorithm in ANNs training is performed, based on the case study of water temperature forecasting in a natural stream, namely Biala Tarnowska river in southern Poland. Over 50 variants of 22 various metaheuristics, including a large number of Differential Evolution, as well as some Particle Swarm Optimization, Evolution Strategies, multialgorithms and Direct Search methods are compared with LM algorithm on ANN training for the described case study. The impact of population size and some control parameters of particular metaheuristics on the ANN training performance are verified. It is found that despite widely claimed large improvement in nature-inspired methods during last years, the vast majority of them are still outperformed by LM algorithm on the selected problem. The only methods that, based on this case study, seem competitive to LM algorithm in terms of the final performance (but not speed) are Differential Evolution algorithms that benefit from the concept of Global and Local neighborhood-based mutation operators. The streamwater forecasting performance of the neural networks is adequate, the major prediction errors are related to the river freezing and melting processes that occur during winter in the mountainous catchment under study. [Copyright &y& Elsevier]

Abstract: With increased global concerns on climate change, the need for innovative spaces which can provide thermal comfort and energy efficiency is also increasing. This paper analyses the effects of transitional spaces on energy performance and indoor thermal comfort of low-rise dwellings in the Netherlands, at present and projected in 2050. For this analysis the four climate scenarios for 2050 from the Royal Dutch Meteorological Institute (KNMI) were used. Including a courtyard within a Dutch terraced dwelling on the one hand showed an increase in annual heating energy demand but on the other hand a decrease in the number of summer discomfort hours. An atrium integrated into a Dutch terraced dwelling reduced the heating demand but increased the number of discomfort hours in summer. Analysing the monthly energy performance, comfort hours and the climate scenarios indicated that using an open courtyard May through October and an atrium, i.e. a covered courtyard, in the rest of the year establishes an optimum balance between energy use and summer comfort for the severest climate scenario. [Copyright &y& Elsevier]

Abstract: Climate change is of great concern for society today. Manufacturing industries and construction account for approximately 20% of global CO2 emissions and, consequently, it is important that this sector investigate options to reduce its CO2 emissions. One option could be to substitute fossil fuels with renewable alternatives. This paper describes a case study in which four future energy market scenarios predicting 2030 were used to analyse whether it would be profitable for a steel plant to produce bio-SNG (bio-synthetic natural gas) in a biomass gasifier and to substitute LPG (liquefied petroleum gas) with bio-SNG as fuel in reheating furnaces. The effects on global CO2 emissions were analysed from a perspective in which biomass is considered a limited resource. The results from the analysis show that investment in a biomass gasifier and fuel conversion would not be profitable in any of the scenarios. Depending on the scenario, the production cost for bio-SNG ranged between 22 and 36 EUR/GJ. Fuel substitution would reduce global CO2 emission if the marginal biomass user is a producer of transportation fuel. However, if the marginal user of biomass is a coal power plant with wood co-firing, the result would be increased global CO2 emissions. [Copyright &y& Elsevier]

Abstract: In the tropics, daylighting from a side window requires shading to intercept direct sunlight from the window whilst allowing penetration of daylight from sky. In this paper, daylighting from a double-pane glazed window with enclosed horizontal slats (slat window) was investigated for which it is situated on either north or south wall of a room. Full-scale experiments and simulations were conducted to characterize distribution of the interior daylight from the slat window under a real tropical climate. Performance of the slat window was evaluated in terms of the “useful daylight illuminance” (UDI), interior daylight availability and light power density (LPD) of an integrated dimmable lighting system. Empirical formulas were developed for determining annual average LPD values of the dimmable lighting system over its served area. The LPD value can be used with a reduced form of the energy equation of Thailand's building energy code to evaluate the reduced annual electrical energy consumption for accreditation of the daylight use in a building. The analysis of life cycle cost proved that the daylighting from the slat window integrated with the dimmable lighting system is cost effective. [Copyright &y& Elsevier]

Abstract: This paper presents a modification of stepped solar still through internal reflectors. A comparison study between modified stepped solar still with trays (5mm depth×120mm width) and conventional solar still was carried out to evaluate the developed desalination system performance under the same climate conditions. The effect of installing a reflecting mirror on the vertical sides of the steps of stepped still on the distillate productivity was investigated. An experimental as well as theoretical investigation is carried out. The results indicate that, during experimentation the productivity of the modified stepped solar still with and without internal reflectors is higher than that for conventional still approximately by 75% and 57%, respectively. Also the daily efficiency for modified stepped still with and without internal reflectors and conventional solar still is approximately 56%, 53% and 34%, respectively. [Copyright &y& Elsevier]

Abstract: Several studies show the potential benefits achievable by recurring to roof vegetation. Really, little literature investigates the economic feasibility of such solution. The paper verifies utility of green roofs, under environmental and energy point of views, by considering all the aspects that influence their performances. With reference to several climates, intensity of rainfalls, needs of irrigation and kind of building use, a large parametric analysis evaluates the technical and economical feasibility of green roofs applied to a modern office building, considering various vegetations and different external coatings. The scarce amount of rainfall – and thus the irrigation cost – can nullify the savings in energy demand for air-conditioning. Moreover, even if green roofs show satisfactory performance if monthly rainfalls do not imply significant additional watering – the economic investigation shows scarce convenience for well-insulated buildings, above all if the higher initial cost of a green roof, compared to traditional roofing coating, is computed. Finally, cool roofs, by means of high-reflective and high-emissive coatings, are suitable solutions in warm climates, strongly improving the summer performances, with low extra costs for installation and maintenance. [Copyright &y& Elsevier]

Abstract: Growing energy demand and global climate change are compelling reasons to look for effective utilisation of waste thermal energy and renewable energy resources. Fifteen percent of the electricity produced in the whole world is employed for refrigeration and air-conditioning processes of various kinds. Low-temperature heat operated environment-friendly adsorption cooling systems are emerging as viable alternatives to electricity-driven vapour compression refrigeration systems. Comparatively bigger sizes of adsorption based cooling units, due to their low specific cooling power, are preventing successful commercialization of the technology. Efforts are on to enhance the performance of adsorption systems through improvements in adsorbents properties, use of advanced cycles, etc. Recent application of nano-technology in the development of adsorbent material may be a big step forward towards making this technology competitive with available technologies in the market. This paper traces the evolution of the technology and analyses the obstacles to wide spread use of adsorption chillers. [Copyright &y& Elsevier]

Abstract: The majority of thermal power plants of more than 300 MW use river water for cooling purposes. Increasing water and air temperatures due to climate change can significantly impact the efficiency and the power production of these power plants. In this paper we analyse these impacts by modelling selected German thermal power plant units and their respective cooling systems through dynamic simulation taking into account legal thresholds for heat discharges to river water together with climate data projections (SRES scenarios A1B, A2, and B1). Possible output and efficiency reductions in the future (2011–2040 and 2041–2070) are quantified for thermal power plants with once-through (OTC) and closed-circuit (CCC) cooling systems under current legislative framework. The model validation showed that the chosen System Dynamics approach is appropriate to analyse impacts of climate change on thermal power units. The model results indicate lowest impacts for units with CCC systems: The mean trend for CCC for the A1B scenario (2011–2070) is expected to be −0.10 MW/a and −0.33 MW/a for an OTC system. On a daily basis, the power output of all considered OTC units is reduced down to 66.4% of the nominal capacity, for a single unit even down to 32%. [Copyright &y& Elsevier]

Thermal aspect of solar energy is widely used in the desalination plants. Experimental investigation and mathematical modeling of inverted V-type solar still integrated with drip system are presented in this paper. The experiment is performed in the Kerala climatic conditions (10.8439°N, 76.0328°E), March 2012 at M E S College of Engineering, Kuttippuram. A two segment still of 2 m² is constructed. Experimental investigations on productivity and internal heat transfer are analyzed. The results indicate that the mean standard deviations between theoretical and experimental values are less than 7% (temperature of rippled wick), 8% (temperature of glass in rippled system), 11% (temperature of flat wick), and 7% (temperature of glass in flat system), an average for the working hours of the day. [ABSTRACT FROM AUTHOR]

Abstract: Experimental research carried out on two types of buildings that are the examples of vernacular architecture in Southern Italy, namely the Sassi of Matera and the Trulli of Alberobello are outlined in this paper. Experimental measurements on thermal properties, energy performance and hygrothermal indoor comfort were carried out to validate the numerical code provided by DesignBuilder/EnergyPlus that was used to investigate the buildings on a yearly basis. The very high thermal mass of the building structures give rise to a quasi-constant seasonal indoor temperature with no need for air conditioning in the mid- and peak-summer seasons. The seasonal thermal storage can almost guarantee near the comfort levels using simple heating systems during the cold season. [Copyright &y& Elsevier]

Abstract: This paper presents a comprehensive global uncertainty and sensitivity analysis of daylighting and energy performance for private offices with automated interior roller shades using an advanced integrated thermal and lighting simulation model. The purpose was to identify the more important factors with respect to building thermal and lighting energy performance so as to facilitate decision making in building design stage and simplify further investigation such as optimization analysis. Seven studied parameters were selected: window-to-floor ratio, shading transmittance, shading front and back reflectance, space aspect ratio, insulation thermal resistance and glazing type. The performance metrics include useful daylight illuminance (500–2000lux), annual lighting, heating and cooling demand per unit floor area and annual source energy consumption per unit floor area. The uncertainty analysis is based on the Monte Carlo method with Latin Hypercube Sampling, showing the possible ranges in these performance indices. The sensitivity analysis uses a variance-based method in the extended FAST implementation. Application of the analysis to perimeter private office spaces for the climate of Philadelphia showed the first order and total order effects of each studied parameter to determine the building parameters that have the most significant impact. Results are presented for different facade orientations. [Copyright &y& Elsevier]

Abstract: This study examines a scenario for realizing large-scale reductions of operational carbon dioxide (CO2) emission in commercial districts in temperate and tropical zones. In warm climates, energy usage for heating is not dominant in a building''s energy usage, and hence, every available emission reduction technology must be fully utilized to achieve a large overall reduction in emissions, as in the scenario examined in this study. The focus is on commercial buildings in Nakanoshima area, a sandbank 3 km long and 50 ha wide, a central business and cultural area in the city of Osaka, Japan. The commercial buildings in Nakanoshima with approximately 1.2 million square meters of total floor area emitted 88 thousand tons of CO2 in 2008. The method used in this paper combines: 1) energy flow analysis, 2) community-scale building performance simulation validated with actual energy consumption and supported by detailed field survey and reference survey, and 3) what-if analysis assuming technological deployment and social change based on a long-term perspective. It enables a comprehensive understanding of how much energy is consumed for what purpose as well as how much energy can be reduced by implementing which technologies and measures. The result showed that approximately 65% emissions of the present operational CO2 emission could be reduced in the coming decades. [Copyright &y& Elsevier]

Abstract: Valid and reliable measurement of countries’ climate policy performance is important both for policy-making and analytical purposes. The authors contribute to this end by introducing a new dataset that offers such information for up to 172 countries for the time period 1996–2008. Their Climate Change Cooperation Index (C3-I) captures overall performance as well as performance in terms of political behavior (output) and emissions (outcome). The C3-I, thus, allows for a systematic global comparison of countries’ climate policies. The paper also compares the C3-I with its most relevant alternative, the Climate Change Performance Index (CCPI) by Germanwatch. [Copyright &y& Elsevier]

Abstract: This paper deals with an experimental investigation of the effect of the working fluid inventory on the performance of the gravity assisted solar heat pipe. Measurements of solar flux and the temperature in different positions over the heat pipe have permitted us to evaluate the performance of the system for different working conditions. Results prove that the optimum performance is observed when the 2/3 of evaporator volume is filled with methanol. [Copyright &y& Elsevier]

Abstract: Glulam structures in service may exhibit considerable moisture induced stresses perpendicular to grain that may affect the load-bearing capacity. An option to enhance the low tensile strength of glulam perpendicular to grain is the use of self-tapping screws, which has shown promising results in constant climates. In varying climates, however, the performance of such screw reinforcements is currently not well understood. The present paper reports results of both experiments and numerical simulations investigating the effect of self-tapping screws on moisture induced stresses arising in glulam exposed to single wetting and drying climate changes. It is shown that during wetting, the screw reinforcement significantly reduces the maximum tensile stresses arising in the cross section centre. With screw distances from 70 to 210mm, stress reductions by 70–30% are achieved (compared to unreinforced glulam beams). The tensile stresses arising between the reinforcing screws depend not only on the screw distance, but also strongly on the cross section width and the annual ring pattern of the laminates. During drying, the additional restraint caused by the reinforcing screws resulted in a slight increase of the tensile stresses at the cross section border. These were, however, rather low compared to the tensile stresses arising during wetting. [Copyright &y& Elsevier]

Abstract: Improving the management of carbon emissions and the development of cleaner production can be a demanding challenge for business and industry. Within this, accounting for carbon management requires quantification of a firm’s direct and indirect emissions. Unfortunately, however, there is a lack of concepts and tools suitable for use in the measurement of carbon performance both in the production process as well as in the supply chain as a whole. The purpose of this paper is, therefore, to explore the role of environmental management accounting and, in particular, the eco-control approach for carbon management as part of the management of a firm’s supply chain. Employing a case study of Korean automobile manufacturers, we explore the roles and usefulness of eco-control as a means of identifying and measuring carbon performance in a production plant. This study finds that eco-control can foster alignment between a firm’s carbon management strategy and carbon performance measurement, and provides useful quantified information for corporate decision makers. In addition, viable mapping of carbon flow in production provides important opportunities to improve carbon performance within the supply chain. [Copyright &y& Elsevier]

This paper presents results from research conducted to provide a high level techno-economic and performance assessments of various emerging technologies for capturing C02 from the air, directly and indirectly, on a life-cycle basis. The technologies assessed include 'artificial trees', the soda lime process, augmented ocean disposal, biochar and bio-energy with carbon capture and storage. These technologies are subjected to quantitative and qualitative analyses, based on the most recent peer reviewed data in the literature, to identify their potential performance as well as the technical and non-technical barriers to their adoption and scale up. Key findings for each technology are presented which seek to highlight the state of technological development and research needs, the anticipated life cycle capture cost in $/tCO2 based on their potential to deliver a 0.1 ppm CO2 reduction per annum, policy requirements for scale up and, in light of these findings, the likely role that they will play in addressing climate change and broader environmental issues in the medium to long term. The key finding from the work is that the degree of scale-up required for negative emissions technologies to have a material impact on atmospheric emissions (i.e. at a ppm level) is probably unrealistic in less than 20 years. Therefore, emissions prevention efforts should remain the main focus in addressing climate change and the likely role for negative emissions technologies will be in augmenting a suite of mitigation measures targeting economically or practically difficult emissions. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the impact of a climate change scenario on comfort and energy performance in offices, in relation to the influence of building design and occupants. It focuses on a typical cellular office room in the context of Athens, Greece, as input for a parametric study using the building simulation software EnergyPlus. Three different building design variations are combined with two different occupant scenarios and a standard weather data set as well as the IPCC climate change scenario A2 for 2020, 2050 and 2080. Results are investigated from two different perspectives: For naturally ventilated buildings the evaluation is related to adaptive thermal comfort according to ASHRAE Standard 55 and EN 15251. And for mixed mode context the evaluation is focused on the resulting impact on final energy consumption, greenhouse gas emissions, peak heating and cooling loads and the percentage of working time when the building is free-running. The results indicate a significant impact of the climate change scenarios on adaptive thermal comfort, and they indicate differences in evaluation between ASHRAE Standard 55 and EN 15251. The comparison of climate change, building design and occupant scenarios indicates that building design is the key to thermal comfort optimisation, whereas the major mitigation potential regarding energy consumption and greenhouse gas emissions is related to occupant behaviour. [Copyright &y& Elsevier]

Abstract: This paper evaluates performance of anchored geosynthetic systems (AGS) on stability of slopes under seepage condition using a centrifuge modeling technique. A series of centrifuge tests were carried out at 50 g on unreinforced and AGS slope models, using a centrifuge container equipped with seepage flow simulator. AGS slope models were tested by varying slope inclination, number of anchors and keeping inclination of anchors as constant. The water was allowed to seep through the model slopes during flight at 50 g. Ground anchors were modeled as drilled pre-tensioned anchors using sand epoxy mixture, polyester strand and a plastic tube. An anchor inclination of 15° with the horizontal was adopted for AGS slopes. A layer of geocomposite was used for modeling geosynthetic component of anchored geosynthetic systems. All models were instrumented to measure surface settlements and pore water pressure within the slope at onset of seepage during centrifuge test. A digital image analysis technique was adopted to trace displacement vectors of plastic markers embedded toward the front elevation of the model and plastic markers glued to facing during model construction. Analysis and interpretation of centrifuge model test results indicate that the stability and deformation behavior of slopes, under seepage conditions, can be substantially improved using anchored geosynthetic systems. With an increase in slope inclination and reduction in number of anchors, surface settlements and face movements were observed to increase substantially. Further, stability analysis results on the unreinforced and AGS slope models were found to be in good agreement with those of physically observed centrifuge test results. [Copyright &y& Elsevier]

Abstract: For decades, residential and commercial roofs have been considered a prime location for installation of building integrated solar systems. In climatic conditions of East Tennessee, USA, an experimental solar roof was tested during 2009/2010, by a research team representing Metal Construction Association (MCA), and a consortium of building insulation companies, photovoltaic (PV) manufacturers, and energy research centers. The main objective was to thermally evaluate a new roofing technology utilizing amorphous silicon PV laminates integrated with the metal roof panels. In order to mitigate thermal bridging and reduce roof-generated thermal loads, this novel roof/attic assembly contained a phase change material (PCM) heat sink, a ventilated air cavity over the roof deck, and thermal insulation with an integrated reflective surface. During winter, the experimental roof was expected to work as a passive solar collector storing solar heat absorbed during the day, and increasing overall attic air temperature during the night. During summer, the PCM was expected to act as a heat sink, reducing the heat gained by the attic and consequently, lowering the building cooling-loads. In this paper, field thermal performance data of the experimental PV-PCM roof/attic system are presented and discussed. Performance of the PV-PCM roof/attic is evaluated by comparing it to a control asphalt shingle roof. The test results showed about 30% heating and 50% cooling load reductions are possible with the experimental roof configuration. [Copyright &y& Elsevier]

Abstract: In cooling buildings, the use of solar energy can save around 50% of primary energy. Many studies have demonstrated the interest of such systems. However, developing and improving reliability of new components, design, control, and implementation remain a major concern. The performances of solar cooling systems are greatly influenced by climatic conditions. Indeed they affect both the driving energy of the chiller and the heat rejection. It is important to mention that internal loads and control strategy also have an impact on energy performances. Therefore, assessing the energy performance during the design phase is a key point in evaluating the economic interest of an installation. Moreover, once the commissioning of the installation is accomplished, there is a need to follow through and ensure its performance, since a large number of malfunctions can affect the quality of the system. Actual performances can be very different from those calculated in the design phase. With this aim, the present article deals with the development of an absorption chiller model used in an existing solar cooling system. This installation includes a single effect absorption chiller with a nominal chilling capacity of 30kW (EAW LB30 chiller functioning with water and lithium bromide), and it cools four classrooms of a University building in Reunion Island which is situated under a tropical climate. This pilot plant is very good monitored and can thus be used to develop and validate the absorption chiller model. The present paper first recalls the absorption principle and presents the pilot plant, the metrology, and the control strategy. Secondly, the experimental results are analysed and the steady state chiller model and also the identification method are developed. Thereafter, the simplex method is used to determine the design parameters of the machine. Finally, the simulation results are presented. The good agreement between the prediction and the experimental results allows the use of the model not only to design an installation but also to follow and control its performances. [Copyright &y& Elsevier]

Abstract: Since July 2008, a Solar Desiccant Evaporative Cooling (DEC) system has been operating as a test plant at the solar laboratory of the Dipartimento di Energia (ex DREAM) of the University of Palermo. The system is composed of an air handling unit (AHU) designed for ventilation of the laboratory coupled with a radiant ceiling that provides most of the required sensible cooling/heating energy. Flat plate collectors deliver part of the regeneration heat of the desiccant wheel during the summertime and are used for space heating during the wintertime. The system was designed for high humidity loads because of the typical climate conditions at the site and the need to support a radiant ceiling for sensible cooling. A hybrid configuration was chosen that uses two auxiliary cooling coils fed by a conventional compression chiller. One coil is used for pre-dehumidification. The other coil controls the air temperature if the desired supply temperature cannot be reached through indirect evaporative cooling alone. A specific feature of the system is the use of the heat rejected by the chiller to preheat regeneration airflow. The plant was monitored continuously after installation and start up phases were completed. This paper presents instantaneous, daily and monthly energy performance indicators for five summer months and three winter months. Monthly results are also presented and elaborated upon according to a monitoring procedure developed in the framework of the International Energy Agency (IEA) Task 38 “Solar Air Conditioning and Refrigeration” of the Solar Heating and Cooling Programme. Seasonal performance indicators such as electric and thermal COP and primary energy savings for cooling and heating operation are presented. It was found that about half of the total cooling energy delivered by the AHU was covered by the DEC process. Primary energy savings in summer, in comparison to a conventional AHU, came up to nearly 50%. The recovery of the heat rejected by the refrigerator was found as a good solution, permitting to reduce solar collector area in the design phase. Finally, main issues arisen from plant monitoring and possible solutions to enhance its energy performances are discussed. [Copyright &y& Elsevier]

Abstract: This paper investigates the effect of changing cell temperature and solar irradiance on the choice and design of different topologies of DC–DC converter commonly used in photovoltaic (PV) systems. Under fluctuation of climatic conditions, the maximum power point (MPP) of PV generator will change. The maximum power point tracker (MPPT) must adjust the converter duty cycle to track the new MPP. Thus the converter must be chosen to be able to match the MPP under different atmospheric conditions. In addition, when the duty cycle changes as a result of changed climatic conditions, the boundary of the converter design parameters will change. So these parameters must be chosen to achieve the highest performance at all. The study shows that, only the buck–boost and the C′uk converter are capable of achieving the optimal operation regardless of the load value. And for a permanent operation in continuous conduction mode the filter inductance for all converter topologies must be greater than the maximum value of boundary inductance. Also in order to limit the ripple in the output voltage below a certain value, the filter capacitance must be larger than the maximum value of boundary capacitance. [Copyright &y& Elsevier]

Abstract: Many parameters have been used to evaluate the thermal performance of envelope wall/roofs, most of them for air-conditioned buildings. In this paper, the interest is focused on parameters to assess the thermal performance of envelope wall/roofs for non air-conditioned buildings. Five groups of parameters, some previously used and some newly proposed, have been analyzed. To test the evaluation parameters, numerical simulations of the periodic heat transfer through five different roof configurations have been carried out. This research shows the suitability of the energy transferred through the wall/roof during a day, the decrement factor, the discomfort degree hours, and the hot (or cold) thermal performance index to be used for thermal evaluation of wall/roofs in non air-conditioned buildings. The sensitivity of these parameters with climatic conditions and with the outdoor surface solar absorptance is analyzed. Additionally, it has been shown that the steady-state thermal transmittance, the thermal admittance modulus, the periodic thermal transmittance modulus, and the surface decrement factor, calculated with surface temperatures, are not suitable parameters to evaluate wall/roofs in non air-conditioned buildings. [Copyright &y& Elsevier]

Abstract: Hainan province is the only tropical and island province in China, with the unique climatic and geographical features. It has a different energy performance in public buildings from those in the inland areas. This paper investigated the current situation of energy consumption of the sampled public buildings, including 26 hotels, 24 office buildings and 7 department stores, through analyzing utility billing data, on-site survey and measurement, and site operational records. The breakdowns of energy consumption found out that the electricity dominated the energy consumption for all the sampled buildings and the air conditioning system played a key role in the energy consumption of major building services. By analyzing the main factors for building energy consumption, the annual average energy use indexes were calculated to be 141.63kWh/m2, 87.70kWh/m2, and 166.95kWh/m2 for hotels, office buildings and department stores, respectively. Besides, the comparison between Hainan province and other areas revealed that the building energy consumption of this tropical province was at a low level. Because indoor environment quality can influence the health and work efficiency of humans in buildings, field tests on the indoor environment quality were also carried out, and the performance of indoor environment quality was rated. [Copyright &y& Elsevier]

Abstract: In response to growing concerns over climate change and rising energy costs, a number of eco-feedback systems are being tested by researchers. Yet, the interface design aspect of these systems has largely been ignored. Therefore, the role that interface design plays at the component level in driving actual energy savings from users is unclear. In this paper, we evaluate the impact interface design has on eco-feedback performance by investigating five established design components. We conducted a six week empirical study with 43 participants using a prototype eco-feedback interface. Analysis of usage data affirmed a statistically significant inverse correlation between user engagement (measured as logins) and energy consumption. Utilizing this relationship as a basis for performance, we expanded our analysis to evaluate the five design components. The study revealed statistically significant evidence corroborating that historical comparison and incentives are design components that drive higher engagement and thus reductions in energy consumption. Results for the normative comparison and disaggregation components were inconclusive, while results for the rewards and penalization component suggest that a revision to the penalization aspect of the component may be necessary. This study raises pertinent questions regarding the efficacy of various eco-feedback components in eliciting energy savings. [Copyright &y& Elsevier]

Uncertainties in predictive models for concrete structures performance can influence adversely the timing of management activities. A methodology has been developed that uses data obtained through proactive health monitoring to increase the confidence in predicted performance by reducing the associated uncertainties. Due to temporal and spatial variations associated with climatic changes, exposure conditions, workmanship, and concrete quality, the actual performance could vary at different locations of the member. In this respect, the use of multiple sensors may be beneficial, notwithstanding cost and other constraints. Two distinct cases are identified for which an updating methodology based on data from multiple sensors needs to be developed. In the first case the interest lies in improving the performance prediction for an entire member (or a structure) incorporating spatial and temporal effects. For this purpose, the member is divided into small zones with the assumption that a sensor can be located in each zone. In the second case, the objective is to minimise uncertainties in performance prediction, or to increase the redundancy of health monitoring systems, at critical locations. The development of updating methodologies for the above-mentioned scenarios is described in this paper. Its implications on the management activities, for example, establishing the timing of principal inspections, are evaluated and discussed. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the idea that plasticity in farm management introduces resilience to change and allows farm businesses to perform when operating in highly variable environments. We also argue for the need to develop and apply more integrative assessments of farm performance that combine the use of modelling tools with deliberative processes involving farmers and researchers in a co-learning process, to more effectively identify and implement more productive and resilient farm businesses. In a plastic farming system, farm management is highly contingent on environmental conditions. In plastic farming systems farm managers constantly vary crops and inputs based on the availability of limited and variable resources (e.g. land, water, finances, labour, machinery, etc.), and signals from its operating environment (e.g. climate, markets), with the objective of maximising a number of, often competing, objectives (e.g. maximise profits, minimise risks, etc.). In contrast in more rigid farming systems farm management is more calendar driven and relatively fixed sequences of crops are regularly followed over time and across the farm. Here we describe the application of a whole farm simulation model to (i) compare, in silico, the sensitivity of two farming systems designs of contrasting levels of plasticity, operating in two contrasting environments, when exposed to a stressor in the form of climate change scenarios;(ii) investigate the presence of interactions and feedbacks at the field and farm levels capable of modifying the intensity and direction of the responses to climate signals; and (iii) discuss the need for the development and application of more integrative assessments in the analysis of impacts and adaptation options to climate change. In both environments, the more plastic farm management strategy had higher median profits and was less risky for the baseline and less intensive climate change scenarios (2030). However, for the more severe climate change scenarios (2070), the benefit of plastic strategies tended to disappear. These results suggest that, to a point, farming systems having higher levels of plasticity would enable farmers to more effectively respond to climate shifts, thus ensuring the economic viability of the farm business. Though, as the intensity of the stress increases (e.g. 2070 climate change scenario) more significant changes in the farming system might be required to adapt. We also found that in the case studies analysed here, most of the impacts from the climate change scenarios on farm profit and economic risk originated from important reductions in cropping intensity and changes in crop mix rather than from changes in the yields of individual crops. Changes in cropping intensity and crop mix were explained by the combination of reductions in the number of sowing opportunities around critical times in the cropping calendar, and to operational constraints at the whole farm level i.e. limited work capacity in an environment having fewer and more concentrated sowing opportunities. This indicates that indirect impacts from shifts in climate on farm operations can be more important than direct impacts from climate on the yield of individual crops. The results suggest that due to the complexity of farm businesses, impact assessments and opportunities for adaptation to climate change might also need to be pursued at higher integration levels than the crop or the field. We conclude that plasticity can be a desirable characteristic in farming systems operating in highly variable environments, and that integrated whole farm systems analyses of impacts and adaptation to climate change are required to identify important interactions between farm management decision rules, availability of resources, and farmer''s preference. [Copyright &y& Elsevier]

Abstract: This paper presents the performance evaluation of a hybrid photovoltaic thermal (Semi transparent PVT) double pass facade for space heating. The thermal model has been developed by using the energy balance equations of the proposed hybrid photovoltaic thermal double pass facade under quasi-steady state condition. Numerical computations have been carried out for the composite climate of New Delhi, India. An analysis has been carried out to calculate annual energy and exergy gain for the hybrid photovoltaic thermal double pass facade. On the basis of numerical results it has been observed that the annual thermal and electrical energy are 480.81kWh and 469.87kWh respectively. The yearly overall thermal energy generated by the system has been calculated as 1729.84kWh. It is also observed that the room air temperature increases by 5–6°C than the ambient air temperature for a typical winter day. [Copyright &y& Elsevier]

Abstract: Efforts towards decarbonizing the energy system have to focus on individual actors within the system. Their current and potential future stake in energy consumption and contribution to climate change has to be analyzed when formulating energy policies targeting system-wide reduction efforts. Focusing on firms, this paper develops a framework for the assessment of corporate carbon performance. We use this framework for an empirical assessment of the 100 largest US electricity producers within three different carbon scenarios. Our results show that in a scenario without changes in the US institutional environment electricity producers will not face a severe increase of their carbon exposure and only a small improvement regarding the carbon intensity of the electricity mix is achieved. In a scenario with more carbon-constrained US energy market conditions some companies face a financial risk from using and emitting carbon that more than triples compared to today. However, in a scenario with strong investments in renewable energy technologies the carbon dependency of electricity production can be significantly reduced. We discuss these findings from a climate policy and financial markets perspective. [Copyright &y& Elsevier]

Abstract: In response to the EU Landfill Directive and the challenge of mitigating climate change, the UK government (nationally and locally) must develop strategies and policies to reduce, recycle, compost and recover waste. Best practice services that yield high recycling rates, such as alternate weekly collections, are now largely mainstream in suitable areas. However, national recycling performance is short of what is needed; policy makers must look for innovative ways to meet challenging recycling targets. Increasingly, local authorities are using behaviour change interventions to encourage the public to recycle; these tend to be based on the premise that an individuals’ behaviour is predetermined by their values. In practice, this has led to a host of initiatives that attempt to change individuals’ behaviour without addressing situational barriers. In this paper, we argue that that a behaviour-centric approach has limited effectiveness. Using an analysis of the literature and studies that investigated recycling participation in the city of Portsmouth, we have identified three significant clusters that can facilitate effective recycling: infrastructure, service and behaviour (ISB). We present the ISB model – a tool that can be used by waste practitioners when planning interventions to maximise recycling to better understand the situation and context for behaviour. Analysis using the ISB model suggests that current best practice, “business as usual” interventions could realistically achieve a national recycling rate of 50%. If the UK is to move towards zero waste, policy makers must look “upstream” for interventions that change the situational landscape. [Copyright &y& Elsevier]

Abstract: The recent paper by Wang and Zender [Wang, X., & Zender, C. S. (2010). MODIS snow albedo bias at high solar zenith angles relative to theory and to in situ observations in Greenland. Remote Sensing of Environment.] draws erroneous conclusions about solar zenith angle biases at high latitudes by not making appropriate use of the extensive quality flags available with the MODIS BRDF/Albedo. Coarse resolution MODIS white-sky albedo data are compared with actual blue-sky field albedometer measurements from the Greenland GC-Net. By utilizing large area averages of the MODIS data product that combine both high quality and poor quality data indiscriminately, the authors erroneously conclude that the accuracy deteriorates for solar zenith angle (SZA)>55° and often becomes physically unrealistic for SZA>65°. Once the quality flags are considered, however, the comparisons demonstrate that the MODIS product performs quite well out to the recommended limit for product use of 70° SZA. This verifies the conclusions of an earlier more rigorous evaluation performed by Stroeve et al. [Stroeve, J., Box, J. E., Gao, F., Liang, S., Nolin, A., & Schaaf, C. B. (2005). Accuracy assessment of the MODIS 16-day albedo product for snow: comparisons with Greenland in situ measurements. Remote Sensing of Environment.]. With over a decade of observations and products now available from the MODIS instrument, these data are increasingly being used to evaluate and tune climate and biogeochemical models. However, such use should take into account the documented quality and limitations of the satellite-derived product. [Copyright &y& Elsevier]

The paper analyses the use of reflectors for increasing the energy performance and output of solar thermal collectors in the Latvian climate conditions. The results of experiments carried out with and without reflectors have shown that for these purposes the economically feasible reflectors which are widely available in Latvia can be employed. [ABSTRACT FROM AUTHOR]

The governments worldwide have initiated programmes for faster adoption of electric vehicles (EVs) to meet the targets of the Paris Climate Change Agreement. One of the major challenges in meeting the targets of EVs' programmes is to develop cost effective and different types of EV drivetrains in a short span of time. One possible way to reduce the development time is to adapt systems and techniques, existing in industry applications, for EV application. Since, EV motor has to operate over a wide speed and torque range, it is necessary to ensure that the controller should have a good dynamic response over the entire operating range. An induction motor-based drivetrain with direct torque control (DTC) is chosen in this work. The DTC suffers from high torque ripple, and it will have an impact on rideability and comfort. To improve the performance of the DTC algorithm, a multi-band error status selection (ESS) method for the torque hysteresis controller is proposed and compared the existing ESS method. The proposed modification in the DTC architecture is tested on an experimental test bed for standard drive cycles used for validation of vehicles. The experimental results show that drive performance is enhanced using the proposed methodology. [ABSTRACT FROM AUTHOR]

Abstract: Thermal performance curves (TPCs) have become key tools for predicting geographical distributions of performance by ectotherms. Such TPC‐based predictions, however, may be sensitive to errors arising from diverse sources. We analysed potential errors that arise from common choices faced by biologists integrating TPCs with climate data by constructing case studies focusing on experimental sets of TPCs and simulating geographical patterns of mean performance. We first analysed differences in geographical patterns of performance derived from two pairs of commonly used TPCs. Mean performance differed most (up to 30%) in regions with relatively constant mean temperatures similar to those at which the TPCs diverged the most. We also analysed the effects of thermal history by comparing geographical estimates derived from (a) a broad TPC based on short‐term measurements of insect larvae (Manduca sexta) with a history of exposure to thermal variation versus (b) a narrow TPC based on long‐term measurements of larvae held at constant temperatures. Estimated mean performance diverged by up to 40%, and differences were magnified in simulated future climates. Finally, to quantify geographical error arising from statistical error in fitted TPCs, we propose and illustrate a bootstrapping technique for establishing 95% prediction intervals on mean performance at each location (pixel). Collectively, our analyses indicate that error arising from several underappreciated sources can significantly affect the mean performance values derived from TPCs, and we suggest that the magnitudes of these errors should be estimated routinely in future studies. [ABSTRACT FROM AUTHOR]

ABSTRACT This study presents the results of dynamically downscaled climate simulations over Italy produced with the COSMO-CLM model. Three simulations forced by ERA-Interim Reanalysis were conducted respectively at a spatial resolution of 0.22°, 0.125° and 0.0715° over the period 1979-2011. The results were analysed in terms of 2-m temperature and precipitation with the aim of assessing the model's ability to reproduce these important features of the Italian climate. The results were validated by comparing model output with different independent observational datasets. Values of temperature and precipitation show a general good agreement with observations, with a fair reduction of errors in all seasons as the resolution is increased. Two simulations at a spatial resolution of 0.0715°, driven by the global model CMCC-CM, were performed over the period 1971-2100, employing the IPCC RCP4.5 and RCP8.5 scenarios. Climate projections show a significant warming expected in Italy at the end of the 21st century, along with a general reduction in precipitation, particularly evident in spring and summer. [ABSTRACT FROM AUTHOR]

A major challenge for fish biologists in the 21st century is to predict the biotic effects of global climate change. With marked changes in biogeographic distribution already in evidence for a variety of aquatic animals, mechanistic explanations for these shifts are being sought, ones that then can be used as a foundation for predictive models of future climatic scenarios. One mechanistic explanation for the thermal performance of fishes that has gained some traction is the oxygen and capacity-limited thermal tolerance ( OCLTT) hypothesis, which suggests that an aquatic organism's capacity to supply oxygen to tissues becomes limited when body temperature reaches extremes. Central to this hypothesis is an optimum temperature for absolute aerobic scope ( AAS, loosely defined as the capacity to deliver oxygen to tissues beyond a basic need). On either side of this peak for AAS are pejus temperatures that define when AAS falls off and thereby reduces an animal's absolute capacity for activity. This article provides a brief perspective on the potential uses and limitations of some of the key physiological indicators related to aerobic scope in fishes. The intent is that practitioners who attempt predictive ecological applications can better recognize limitations and make better use of the OCLTT hypothesis and its underlying physiology. [ABSTRACT FROM AUTHOR]

It is generally assumed that favourable weather conditions determine the activity levels of lizards, because of their temperature-dependent behavioural performance. Inactivity, however, might have a selective advantage over activity, as it could increase survival by reducing exposure to predators. Consequently, the effects of weather conditions on the activity patterns of lizards should be strongly influenced by the presence of predators. Using remote camera traps, we test the hypothesis that predator presence and weather conditions interact to modulate daily activity levels in two sedentary cordylid lizards, Karusasaurus polyzonus and Ouroborus cataphractus. While both species are closely related and have a fully overlapping distribution, the former is a fast-moving lightly armoured lizard, whereas the latter is a slow-moving heavily armoured lizard. The significant interspecific difference in antipredator morphology and consequently differential vulnerability to aerial and terrestrial predators, allowed us to unravel the effects of predation risk and weather conditions on activity levels. Our results demonstrate that K. polyzonus is predominantly active during summer, when ambient temperatures are favourable enough to permit activity. In contrast, a peak in activity during spring was observed in O. cataphractus, with individuals being inactive during most of summer. While favourable weather conditions had a strong effect on the activity levels of K. polyzonus, no such relationship was present in O. cataphractus. Contrary to our hypothesis, the presence of terrestrial predators does not seem to affect daily activity levels or alter the influence of weather conditions on activity levels. We conclude that inactivity in O. cataphractus appears to be related to seasonal differences in vulnerability to predators, rather than the presence of predators, and highlight the importance of additional selective pressures, such as food abundance, in determining the species’ activity levels. [ABSTRACT FROM AUTHOR]

Animal daily routines represent a compromise between maximizing foraging success and optimizing physiological performance, while minimizing the risk of predation. For ectothermic predators, ambient temperature may also influence daily routines through its effects on physiological performance. Temperatures can fluctuate significantly over the diel cycle and ectotherms may synchronize behaviour to match thermal regimes in order to optimize fitness. We used bio-logging to quantify activity and body temperature of blacktip reef sharks (Carcharhinus melanopterus) at a tropical atoll. Behavioural observations were used to concurrently measure bite rates in herbivorous reef fishes, as an index of activity for potential diurnal prey. Sharks showed early evening peaks in activity, particularly during ebbing high tides, while body temperatures peaked several hours prior to the period of maximal activity. Herbivores also displayed peaks in activity several hours earlier than the peaks in shark activity. Sharks appeared to be least active while their body temperatures were highest and most active while temperatures were cooling, although we hypothesize that due to thermal inertia they were still warmer than their smaller prey during this period. Sharks may be most active during early evening periods as they have a sensory advantage under low light conditions and/or a thermal advantage over cooler prey. Sharks swam into shallow water during daytime low tide periods potentially to warm up and increase rates of digestion before the nocturnal activity period, which may be a strategy to maximize ingestion rates. “Hunt warm, rest warmer” may help explain the early evening activity seen in other ectothermic predators. [ABSTRACT FROM AUTHOR]

Lake Victoria, the second largest freshwater lake in the world, plays a crucial role in the hydrology of equatorial eastern Africa. Understanding how climate change may alter rainfall and evaporation patterns is thus of vital importance for the economic development and the livelihood of the region. Regional rainfall distribution appears, up to a large extent, to be controlled by local drivers which may be not well resolved in general circulation model simulations. We investigate the performance over the Lake Victoria basin of an ensemble of UK Met Office Hadley Centre regional climate model (HadRM3P) simulations at 50 km, driven by five members of the Hadley Centre global perturbed-physics ensemble (QUMP). This is part of the validation of an ensemble of simulations that has been used to assess the impacts of climate change over the continent over the period 1950-2099. We find that the regional climate model is able to simulate a lake/land breeze over Lake Victoria, which is a significant improvement over the driving global climate model and a vital step towards reproducing precipitation characteristics in the region. The local precipitation correlates well with large-scale processes in the Pacific Ocean and Indian Ocean, which is in agreement with observations. We find that the spatial pattern of precipitation in the region and the diurnal cycle of convection is well represented although the amount of rainfall over the lake appears to be overestimated in most seasons. Reducing the observational uncertainty in precipitation over the lake through future field campaigns would enable this model bias to be better quantified. We conclude that increasing the spatial resolution of the model significantly improves its ability to simulate the current climate of the Lake Victoria basin. We suggest that, despite the higher computational costs, the inclusion of a model which allows two-way interactions between the lake and its surroundings should be seriously considered for any new climate projections for the region. [ABSTRACT FROM AUTHOR]

Model performance and future projection of Arctic summertime storm-track activity and associated background states are assessed on the basis of Coupled Model Intercomparison Project Phase 3 (CMIP3)/5 (CMIP5) climate models. Despite some improvement in the CMIP5 models relative to the CMIP3 models, most of the climate models underestimate summertime storm-track activity over the Arctic Ocean compared to six reanalysis data sets as measured locally as the variance of subweekly fluctuations of sea level pressure. Its large inter-model spread (i.e., model-to-model differences) is correlated with that of the intensity of the Beaufort Sea High and the lower-tropospheric westerlies in the Arctic region. Most of the CMIP3/5 models project the enhancement of storm-track activity over the Arctic Ocean off the eastern Siberian and Alaskan coasts, the region called the Arctic Ocean Cyclone Maximum, in association with the strengthening of the westerlies in the warmed climate. A model with stronger enhancement of the storm-track activity tends to accompany stronger land-sea contrast in surface air temperature across the Siberian coast, which reflects greater surface warming over the continent and slower warming over the Arctic Ocean. Other processes, however, may also be likely to contribute to the future changes of the storm-track activity, which gives uncertainty in the projection by multiple climate models. Our analysis suggests that further clarification of those processes that influence storm-track activity over the Arctic is necessary for more reliable future projections of the Arctic climate. [ABSTRACT FROM AUTHOR]

There is increasing evidence that behavioral flexibility is associated with the ability to adaptively respond to environmental change. Flexibility can be advantageous in some contexts such as exploiting novel resources, but it may come at a cost of accuracy or performance in ecologically relevant tasks, such as foraging. Such trade-offs may, in part, explain why individuals within a species are not equally flexible. Here, we conducted a reversal learning task and predation experiment on a top fish predator, the Northern pike ( Esox lucius), to examine individual variation in flexibility and test the hypothesis that an individual's behavioral flexibility is negatively related with its foraging performance. Pikes were trained to receive a food reward from either a red or blue cup and then the color of the rewarded cup was reversed. We found that pike improved over time in how quickly they oriented to the rewarded cup, but there was a bias toward the color red. Moreover, there was substantial variation among individuals in their ability to overcome this red bias and switch from an unrewarded red cup to the rewarded blue cup, which we interpret as consistent variation among individuals in behavioral flexibility. Furthermore, individual differences in behavioral flexibility were negatively associated with foraging performance on ecologically relevant stickleback prey. Our data indicate that individuals cannot be both behaviorally flexible and efficient predators, suggesting a trade-off between these two traits. [ABSTRACT FROM AUTHOR]

The last two decades have witnessed an explosion in the publication of country indexes that measure and rank the relative national policy performances of governments. To illustrate the challenges of using and applying these tools we focus on those four indexes that have been specifically designed in response to the emergence of the relatively new policy area of climate change. We investigate if and how these tools provide information about the evolving landscape of climate policy in the BRIC (Brazil, Russia, India and China) countries, widely considered the future battleground of climate policy. We find that even for this relatively narrow area different methodologies exist. Interpreting and applying climate policy indexes across countries therefore requires a solid understanding of underlying objectives and data used for each index. A clear gap is the underrepresentation of adaptation policy in all four indexes. Our investigation concludes with a reflection on how climate policy indexes are currently applied, including business planning. These tools provide informative pointers that can be of use for stakeholders, nevertheless they should not be considered in isolation, but need to be complemented by a broader view on what is driving particular responses to climate change in a country. [ABSTRACT FROM AUTHOR]