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• Four façade integrated solar cooling systems have been investigated. • The systems apply façade integrated either solar electric (PVs) or solar thermal collectors. • The optimum façade orientations and system sizing have been determined. • Their technical and financial performance parameters have been compared. • Solar fraction and unit cooling cost are the performance parameters compared. Solar cooling technologies have been proven to have great potential for energy saving during cooling season. Meanwhile, glass has become one of the primary structural materials used in building construction since the middle of the 20th century. Although common glass adds to the aesthetic appeal of a building, it has serious drawbacks, such as creating heat traps, preventing natural ventilation and causing glare. Highly glazed façades would cause unwanted heat transmission from the ambient, which must be extracted to outside using an air-conditioning system. Internal heat resulting from façade configurations can be responsible for up to 45% of a building's cooling requirements. A façade integrated solar cooling system can simultaneously improve building's energy efficiency, utilise solar energy and still maintain a high level of architectural and aesthetic quality. This investigation presents a consistent approach for optimising and comparing façade integrated solar cooling systems in terms of technical and financial performance. Four systems (a vapour compression cycle (VCC) chiller driven by semi-transparent photovoltaics (STPV) arrays, a single-stage absorption chiller, an adsorption chiller and a vapour compression chiller coupled with organic Rankine cycle (ORC) driven by evacuated tube solar collectors) were assessed and compared with a conventional electric vapour compression chiller. The systems investigated were modelled in TRNSYS and the models were applied to predict performance parameters in various climate zones (seven cities) in Australia. The solar fraction (SF) and unit cooling cost (UCC) were the two parameters applied to quantify the technical and financial aspects of each solar cooling system in seven cities in Australia. It was found that among the systems investigated, the VCC chiller with STPV system has the highest SF (100% except in Darwin) and lowest UCC ($0.21 kWh r −1) for all seven cities in Australia. In general, due to the grid as a virtual storage, ORC-VCC system has higher SF (40% and 50%) and lower UCC (5% and 10%) compared with adsorption and absorption chiller respectively in subtropical and temperate climate zones. [ABSTRACT FROM AUTHOR]

Objectives Temperature observation time and type influenced the assessment of heat impact on mortality, and different health events may have different temperature thresholds beyond which these health events increase substantially. This study aimed to investigate whether temperature observation time and type influenced the assessment of heatwave impact on morbidity, to assess how heatwave duration modified heatwave impact on morbidity, and to examine whether there was a consistent temperature threshold beyond which five different types of health events increased sharply. Methods Minutely air temperature data in Brisbane, Australia, were collected and converted into five daily temperature indicators observed at different time points or calculated using different approaches. Twenty-nine heatwave definitions for each temperature indicator were used to examine the effects of heatwaves on five health events (i.e., ambulance service uses, emergency department attendances (EDAs), hospitalizations, possible EDAs of heat and/or dehydration, and possible hospitalizations of heat and/or dehydration) by quasi-Poisson models. Results Mean temperature was slightly better than maximum temperature in predicting heatwave impact on morbidity (P < 0.05), and no appreciable difference in model performance was observed amongst different mean temperature indicators. Two-day-duration heatwaves were more detrimental than longer-lasting heatwaves when heatwave intensity was not high, and 97th percentile appeared to be a consistent temperature threshold for most heatwave-related health events (P < 0.05). Conclusions It seems desirable in the development of heatwave definition and early warning systems to use mean temperature as an exposure indicator, and to adopt the 97th percentile of temperature as the trigger in Brisbane. Health sectors need to better prepare for short-lasting heatwaves. [ABSTRACT FROM AUTHOR]

While surface heat flow relates to the heat loss through the lithosphere, it can be difficult to quantify and separate the heat produced internally through radiogenic decay from the heat transferred across the base of the lithosphere by mantle convection. In this study, we apply a thermo-isostatic analysis to Australia and estimate the sub-lithospheric and radiogenic heat flow components by employing a simple 1-D conservation of energy model. We estimate an anomalous radiogenic heat production across much of eastern Australia generally accounting for >50 mW m −2 , while western Australia appears to have high crustal compositionally corrected elevation, possibly related to chemical buoyancy of the mantle lithosphere. A moderately high sub-lithospheric heat flow (∼40 mW m −2 ) along the eastern and southeastern coast, including Tasmania, is coincident with locations of Cenozoic volcanism and supports an edge-driven convection hypothesis. However, the pattern of sub-lithospheric heat flow along the margin does not support the existence of hotspot tracks. Thermo-isostatic models such as these improve our ability to identify and quantify crustal from mantle sources of heat loss and add valuable constraints on tectonic and geodynamic models of the continental lithosphere's physical state and evolution. [ABSTRACT FROM AUTHOR]

Better understanding is needed of building thermal performance as a mediator between climate and health outcomes. There is concern that current dwelling energy conservation strategies that focus on keeping warm in winter may lead to overheating and heat stress in summer or an increased use of cooling energy. Drawing on public health methodologies to predict heat related health outcomes, this study has standardised three-day averaged mean indoor to outdoor temperatures from 107 homes in Melbourne, Australia, to test the influence of the residential energy efficiency rating on the living room temperatures in summer. At the heat wave threshold of 25 °C, on average, better rated 6-Star homes were 0.89 °C warmer than 4- or 5-Star rated homes. At this reference temperature, air-conditioned 6-Star homes used 15.84 kWh/day electric cooling energy more to achieve the same living room temperature as 3-Star rated homes. The findings confirm the results of simulation studies that found increased fabric insulation may be associated with increased summer indoor temperatures, risk of heat stress and cooling energy in a mild temperate climate. Hence, it is recommended that residential thermal performance ratings should evaluate the dwelling's performance for each season independently and that cooling through natural ventilation and shading be promoted. [ABSTRACT FROM AUTHOR]

Abstract: Tectonic changes of the Early to Mid-Pliocene largely modified the Indonesian Passages by constricting and uplifting the passages between today''s New Guinea and Sulawesi. The associated changes in strength and water mass properties of the Indonesian throughflow (ITF) might have influenced the amount of heat transported from the Pacific to the Indian Ocean and thus contributed to Pliocene climate change of the Indo-Pacific. We study the climate response to changes in the geometry of the Indonesian Passages in an atmosphere–ocean general circulation model (AOGCM). We compare climate simulations with present-day topography and with a topography resembling the Early Pliocene situation in the Indo-Pacific, i.e. passages East of Sulawesi deepened and widened to the South. We find that transport through the Indonesian Archipelago is weakened in the constricted passage by 1.7Sv and in the unchanged Makassar Strait West of Sulawesi by 3.5Sv, while transport weighted temperature of the outflow into the Indian Ocean increases by 1°C. Consistent with recent proxy evidence the reduction in ITF transport causes a decrease in subsurface temperatures in the Indian Ocean while surface waters of the equatorial Pacific exhibit an increase by up to 0.9°C centred in the warm pool. As a local response to the sea surface temperature anomalies, we observe an anomalous precipitation dipole across the Indonesian passages with increased rainfall over the Pacific warm pool and decreased precipitation in the eastern Indian Ocean. The Australian continent experiences a pronounced aridification with mean annual precipitation rates dropping by 30% over most parts of the continent. Using an uncoupled vegetation model, we demonstrate that the simulated climate change might partly explain the observed Late Pliocene desertification of Australia. [Copyright &y& Elsevier]

Abstract: To address questions concerning the intensity and spatial structure of the three-dimensional circulation within the Pacific Ocean and the associated advective and diffusive property flux divergences, data from approximately 3000 high-quality hydrographic stations collected on 40 zonal and meridional cruises have been merged into a physically consistent model. The majority of the stations were occupied as part of the World Ocean Circulation Experiment (WOCE), which took place in the 1990s. These data are supplemented by a few pre-WOCE surveys of similar quality, and time-averaged direct-velocity and historical hydrographic measurements about the equator. An inverse box model formalism is employed to estimate the absolute along-isopycnal velocity field, the magnitude and spatial distribution of the associated diapycnal flow and the corresponding diapycnal advective and diffusive property flux divergences. The resulting large-scale WOCE Pacific circulation can be described as two shallow overturning cells at mid- to low latitudes, one in each hemisphere, and a single deep cell which brings abyssal waters from the Southern Ocean into the Pacific where they upwell across isopycnals and are returned south as deep waters. Upwelling is seen to occur throughout most of the basin with generally larger dianeutral transport and greater mixing occurring at depth. The derived pattern of ocean heat transport divergence is compared to published results based on air–sea flux estimates. The synthesis suggests a strongly east/west oriented pattern of air–sea heat flux with heat loss to the atmosphere throughout most of the western basins, and a gain of heat throughout the tropics extending poleward through the eastern basins. The calculated meridional heat transport agrees well with previous hydrographic estimates. Consistent with many of the climatologies at a variety of latitudes as well, our meridional heat transport estimates tend toward lower values in both hemispheres. [Copyright &y& Elsevier]

• The typical stripper in the PCC is replaced by an innovative solar stripper (So-St). • The conceptual design for direct solvent regeneration in the solar field is analysed. • A design protocol to calculate So-St segments and modules layout is developed. • The length and diameter of subsequent segments to the overall design is optimized. • The process control for the pressure drop and enhanced heat transfer is maintained. This paper presents an advanced thermodynamic analysis to design a solar stripper (So-St) field to replace the conventional desorption unit in a post-combustion carbon capture (PCC) plant. By eliminating the large, complex, and costly stripper, a solar collector field (SCF) consisting of a number of So-St arrays is sized to directly release the CO 2 gas from the rich solvent under transient conditions. In this study, a design protocol has been developed to address the key design challenges for the evolving two-phase flow in the solar receiver tube analysing the instantaneous flow regime, pressure drop, and vapour molar fraction (VMF) to enhance the heat transfer. This design protocol optimizes the physical properties of the So-St components and eventually leads to the whole So-St field sizing based on the nominal capture capacity. A case-study is demonstrated to capture 1.5M tonne CO2 /y from a representative 660 MW e coal-fired power plant in Sydney/Australia. It is found that 22 rich solvent loops that each consists of an array of 6 parallel So-St modules, where each module consists of 6 segments in series is needed. The length/diameter of these So-St segments/modules are optimized for this case-study, and the design procedures are clarified and simplified which can be easily applied for other case-studies. Techno-economic validation of this novel So-St technology is an essential step-forward to fully solarize and autonomies carbon capture industry. [ABSTRACT FROM AUTHOR]

Energy efficiency of buildings is attracting significant attention from the research community, as the world is moving towards sustainable building designs. The average heat gain is the crucial measure for estimating the energy consumption of the buildings. The Envelope Thermal Transfer Value (ETTV) is a simplistic method of determining average heat gain in buildings through its envelopes considering all heat gain components. It also measures the energy efficiency of buildings without inhibiting the design options. The values of ETTV coefficients highly depend on the climatic conditions, geographical locations and the orientation of the buildings. However, no study has been done to investigate the suitability of applying ETTV approach and to develop ETTV formulations for extreme solar radiation with hot and windy climatic conditions like Australian environments. In addition to this, the relevant studies reported in the literature are not comprehensive enough as the coefficient were developed using limited data and the developed formulations were not applied to a variety of real buildings to validate them. Therefore, the main aim of this study is to develop the coefficients of envelope thermal transfer value for commercial buildings, formulate new ETTV equations for buildings with external shadings and estimate the ETTV based annual cooling energy in the sub-tropical climates of Australia. In this study, real life building data relevant to all heat gain parameters of five existing commercial building have been collected and hourly data of wall conduction, window conduction and solar radiation for 11 different types of wall construction and 54 types of window construction have been analysed to determine coefficients of ETTV. Based on these coefficients, the new formulation of ETTV has been proposed to determine total ETTV value of commercial buildings in sub-tropical climate. The developed formulations have been used to estimate the cooling energy loads of 10 real life buildings. A comparative study has been conducted between these estimated cooling energy consumption based on ETTV, actual building load and simulated cooling energy using commercial software. It was demonstrated that developed equations accurately estimate the building cooling load. The computed values of ETTV are within the range 24–42 W/m2, which can be applied in any air-conditioned commercial building in sub-tropical climate like Australia. [ABSTRACT FROM AUTHOR]

Recently unclassified boards with varying composition and more notably with ambiguous thermal properties are being used in buildings. The fire performance of Light gauge Steel Frame (LSF) wall systems mainly depends on the protective plasterboard linings used and thus fire safety concerns are being raised. Therefore this study was aimed at setting minimum standards for fire-resistant grade plasterboards used in LSF wall applications based on material characterization, thermo-physical properties and finite element heat transfer modelling. The most commonly used fire protective board, gypsum plasterboard was used to address this critical issue. Thermo-physical properties of three gypsum plasterboards manufactured in Australia were measured and compared in relation to their chemical composition in the first phase of the study. Fire resistance levels (FRLs) of LSF wall systems lined with these three plasterboards were determined using 3-D FE heat transfer models of LSF wall systems developed and validated in this study. The paper proposes a "k-factor" based on thermo-physical properties and thickness of plasterboard, capable of giving an overall measure of the fire performance of plasterboard lined LSF walls. Standard k-factor profiles were established for non-load bearing LSF wall systems with FRLs of 60, 120, 180 and 240 min by considering the correlation between the time-temperature profiles from numerical analyses and calculated k-factors. These proposed standard k-factor profiles give an overall measure of the fire performance of plasterboards. This paper presents the details of this study and the results. • Measured thermo-physical properties and chemical composition of three gypsum plasterboards manufactured in Australia. • 3D FE heat transfer models of LSF walls were developed and validated. • FRLs of LSF wall systems lined with the three plasterboards were determined using 3-D FE modelling. • Proposed a "k-factor" based on plasterboard thermo-physical properties and thickness for the fire performance of LSF walls. • Verified the accuracy of the k-factor approach by using the fire test and thermal property results of two other boards. [ABSTRACT FROM AUTHOR]