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Abstract In order to further reduce the impact of climate fluctuations on the typical meteorological year (TMY) database, this paper introduces an ensemble empirical model decomposition method to extract the periodic fluctuation and random fluctuation data from outdoor climate data separately, and to construct a comprehensive description parameter that eliminates the influence of random fluctuation data. An innovative TMY based on the comprehensive description parameter was developed in six selected cities of different climate zones in China. Compared with the existing Chinese TMY development method and outdoor design parameters, it is found that the typical meteorological months (TMMs) of each city and the outdoor design parameters from the improved TMY database have changed to a certain extent. Through the correlation analysis between improved TMY database and the cumulative long-average meteorological data, it reveals that the improved TMY can better describe the local average climatic characteristics. Finally, this paper discusses the impact of the improved TMY on the building heat loss index and outdoor thermal comfort in different building shapes. The results demonstrate that the energy demand and outdoor thermal comfort analysis based on the improved TMY are closer to long-term averaged outdoor climate, and the calculation deviations compared with conventional method are reduced by 1.18%–21.08% and 53.42%–76.82% respectively. This research will refine outdoor climate data for building design and analysis.

Abstract In this paper, a finned heat pipe assisted passive heat sink based on a newly emerging high performance phase change material (PCM), the low melting point metal (LMPM), was developed for thermal buffering of high power electronics which works intermittently with heat generation rate up to 1000 W (10 W/cm2). Firstly, thermal performances of the PCM heat sink under different thermal shocks (from 200 W to 1000 W) were experimentally evaluated, in comparison with that of an organic PCM which has similar melting point. It was found that, the former one can prolong the working duration 1.4–2.4 times that of the latter one. Then, the performance of the heat sink was improved through reducing the contact thermal resistance and by increasing the fin number. Furtherly, an air cooling radiator was configured to accelerate the solidification process of the PCM module, which makes it capable of maintaining its highest temperature below 85 °C under 1000 W periodic thermal shock (10 min on and 15 min off). Moreover, energy dispersive spectrometer (EDS) analysis was conducted to verify the compatibility of the LMPM PCM and the structural materials. Finally, a simplified numerical model was developed and validated for the currently constructed finned heat pipe assisted LMPM PCM heat sink, which can be much helpful for future practical thermal design and optimization of this kind of thermal buffering module.

In recent years, solar absorbers have received widespread attention, however, large‐scale preparation is difficult to achieve for many absorbers, and the raw materials are expensive. Halloysite (HNTs) and palygorskite (PAL) have the advantage of abundant reserves and low prices. Herein, solar absorbers with bilayer and porous features are prepared from mixed clays of HNTs and PAL; further studies focused on the solar–thermal conversion efficiency of the absorbers. The mixed clays are gelated by aqueous polymerization of acrylamide and N, N′‐methylene bisacrylamide, then the surface of the gel is carbonized to obtain the double‐layer solar absorbers (F‐HNTs/PAL). The F‐HNTs/PAL shows excellent thermal stability with a weight‐loss ratio of 13% at 1,000 °C, good mechanical properties with a compressed strength of up to 200 KPa at 80% strain, abundant porosity with an adsorption pore volume of 0.057 cm3 g−1, and low thermal conductivity (0.206 W m−1 K−1). Under 1 sun illumination, the F‐HNTs/PAL has a higher vapor rate of 1.215 kg m−2 h−1 that equals 84% solar‐to‐vapor efficiency, which is much more than 57% of F‐HNTs prepared by the same methods, but the F‐HNTs/PAL shows unique thermal stability and mechanical property.

To fix CO2 emissions efficiently from flue gas of coal-fired power plants, the culture medium, light intensity and bioreactors were comprehensively optimized in the process of CO2 fixation by Chlorella PY-ZU1. To make up for relative insufficiency of nutrients (except for the carbon source) resulting from continuous bubbling of 15% CO2, three chemicals were added into the culture to optimize the molar ratios of nitrogen to carbon, phosphorus to carbon, and magnesium to carbon in culture from 0.17 to 0.69, from 0.093 to 0.096, and from 0.018 to 0.030, respectively. Such adjustments led to a 1.25-fold increase in biomass (from 2.41 to 5.42 g L(-1)). By enhancing light intensity from 4500 to 6000 lux, the peak growth rate of Chlorella PY-ZU1 increased by 99% and reached to 0.95 g L(-1) day(-1). Use of a multi-stage sequential bioreactor notably improved the peak CO2 fixation efficiency to 85.6%.

As efforts to address climate change shift to action at local scales, municipalities are called upon to develop locally specific action plans. Many municipalities lack the resources to develop energy and emissions-reducing policy interventions appropriate to their characteristics. This research synthesises urban form, scenario analysis and energy simulation into a cohesive workflow for evaluating energy and emissions policy interventions across a range of urban forms. A geospatial and census analysis of six cities across British Columbia, Canada, led to the development of seven urban neighborhood patterns. These represent neighborhood forms and densities found in cities of various sizes, densities, forms and climates. To test the approach of an urban built environment model (UBEM), retrofit and infill redevelopment ‘what-if’ scenarios were applied iteratively to two sample patterns comparing the relative efficacy of building technology-improvement policies versus land-use intensification policies. The future ‘what-if’ policy scenarios were spatially tested and validated using relevant policy. The simplified UBEM methods applied to typical patterns and development demonstrates a step towards an accessible and flexible modeling approach. Small and medium-sized municipalities can use this approach to assess and compare potential energy and emissions policy options and outcomes at building and neighborhood scales. 'Practice relevance' A new, simple method has been created for municipalities to understand multiple ‘what-if’ scenarios for reducing energy demand and emissions from buildings. This is based on profiles from census data, geospatial analysis and energy data that characterise urban neighborhood patterns. The approach integrates building-scale and neighborhood-scale energy and greenhouse gas simulations. It can simulate a variety of policy scenarios and strategy interventions in order to show the interactions between and among urban form and retrofit options. This enables planners and decision-makers to compare the relative magnitudes of different interventions at the neighborhood or city level for energy and emissions performance. The model was developed for use by a variety of communities in British Columbia, Canada. There is potential for adapting this method for use in other locations.

Abstract Solid fuels such as firewood and coal are widely used for cooking and heating in the developing countries, which result in serious indoor air pollutions and health effects. Governments and international organizations have been devoted to addressing this issue for a long time. Based on the micro survey data from 1989–2011, this paper quantitatively investigate the situations and evolutions of cooking fuel using and its health effects in rural China. We have four findings: (i) most rural households still rely on solid fuels for cooking in modern China. (ii) the cooking fuels are slowly diversifying in the last two decades, (iii) there are considerably geographical differences in cooking fuel using across China, and (iv) those resident usually using solid fuel have lower levels of self-assessed health and higher prevalence of respiratory diseases. We then draw some policy implications to reduce cooking fuel use.

Thermal generation is a vital component of mature and reliable electricity markets. As the share of renewable electricity in such markets grows, so too do the challenges associated with its variability. Proposed solutions to these challenges typically focus on alternatives to primary generation, such as energy storage, demand side management, or increased interconnection. Less attention is given to the demands placed on conventional thermal generation or its potential for increased flexibility. However, for the foreseeable future, conventional plants will have to operate alongside new renewables and have an essential role in accommodating increasing supply-side variability.\ud \ud This paper explores the role that conventional generation has to play in managing variability through the sub-system case study of Northern Ireland, identifying the significance of specific plant characteristics for reliable system operation. Particular attention is given to the challenges of wind ramping and the need to avoid excessive wind curtailment. Potential for conflict is identified with the role for conventional plant in addressing these two challenges. Market specific strategies for using the existing fleet of generation to reduce the impact of renewable resource variability are proposed, and wider lessons from the approach taken are identified.

Sustainable food supply has gained considerable consumer concern due to the high percentage of spoilage microorganisms. Food industries need to expand advanced technologies that can maintain the nutritive content of foods, enhance the bio-availability of bioactive compounds, provide environmental and economic sustainability, and fulfill consumers’ requirements of sensory characteristics. Heat treatment negatively affects food samples’ nutritional and sensory properties as bioactives are sensitive to high-temperature processing. The need arises for non-thermal processes to reduce food losses, and sustainable developments in preservation, nutritional security, and food safety are crucial parameters for the upcoming era. Non-thermal processes have been successfully approved because they increase food quality, reduce water utilization, decrease emissions, improve energy efficiency, assure clean labeling, and utilize by-products from waste food. These processes include pulsed electric field (PEF), sonication, high-pressure processing (HPP), cold plasma, and pulsed light. This review describes the use of HPP in various processes for sustainable food processing. The influence of this technique on microbial, physicochemical, and nutritional properties of foods for sustainable food supply is discussed. This approach also emphasizes the limitations of this emerging technique. HPP has been successfully analyzed to meet the global requirements. A limited global food source must have a balanced approach to the raw content, water, energy, and nutrient content. HPP showed positive results in reducing microbial spoilage and, at the same time, retains the nutritional value. HPP technology meets the essential requirements for sustainable and clean labeled food production. It requires limited resources to produce nutritionally suitable foods for consumers’ health.