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The pulp and paper industry is a high energy consuming and polluting sector, and carbon emissions emitted from this sector are worthy of attention. This article, based upon an analysis of China’s Pulp and Paper Industry (CPPI), provides estimates of each of the following: carbon emissions from energy consumption, pre-treatment sector, combustion of condensed black liquor, and methane emitted from incomplete aerobic digestion during sewage treatment of CPPI. During the study period (2005–2012), total CO 2 emissions ranged from 126.0 Mt to 155.4 Mt. Energy consumption was estimated to be the largest source of carbon emissions, however, due to the application of the local emission inventory rather than the IPCC inventory, energy consumption decreased by 4.7%, a lower percentage than was calculated in a previous study. According to this study’s estimation, the emissions caused by the recovery of biomass energy contributed 26–29% of the total CO 2 emissions. CH 4 generated from sewage treatment accounted for 9–11% of the total carbon emissions. The CO 2 intensity dropped during the study period, which reflected the improvement of energy efficiency in the pulp and paper industry. The outcome of this study provides not only detailed information about CPPI’s carbon emissions, but also a calculation framework for studying carbon emissions from pulp and paper sector in the other regions. It suggests that the local carbon emissions inventory should be used for estimating carbon emissions and to reduce the fossil fuel energy, increase energy recovery from biomass, and that promoting cleaner production is essential to achieve a low carbon development of the pulp and paper industry. [ABSTRACT FROM AUTHOR]

• This paper systematically reviews the research progress of RS technology applied to various stages of PV system development. • We conclude that RS plays a significant role in PV potential assessment, large-scale data analysis and PV health monitoring. • We discuss future challenges and opportunities for RS technology in PV applications for advancing the research in this area. Developing solar photovoltaic (PV) systems is an effective way to address the problems of limited fossil fuel reserves, soaring world energy demand and global climate change. The earth observation information provides a promising perspective for estimating the PV energy potential and understanding the status of the PV system development, which is critical for making scientifically sound and cost-optimal sustainable planning strategies. Remote sensing (RS), a versatile technology that captures surface information at various temporal and spatial scales, is now widely applied in different fields of the PV development. However, despite the rapid growth of related research, there is still a lack of comprehensive review on the application of RS to different stages (i.e., planning, site selection, installation, maintenance, etc.) of the PV system development. This paper systematically reviews the research progress of RS technology applied throughout various stages of the PV system development. The reviewed literatures are organized as four major parts: i) PV potential estimation, ii) PV array detection, iii) PV fault monitoring and diagnosis, and iv) other cross-cutting areas where RS can facilitate PV development. We conclude that RS technology can bridge the gap caused by the traditional methods in effective assessment of resource potential, large-scale data analysis and PV health monitoring, which can provide strong support in assisting the planning, management, and decision-making of PV systems. Finally, we discuss future challenges and opportunities for RS technology in PV applications for advancing the research in this area. [ABSTRACT FROM AUTHOR]

This paper presents new metrics to measure the effect of thermal mass on the energy required to heat and cool buildings. Previous studies have been flawed as they have not considered the interaction between intermittent occupancy and thermal mass, which has a significant impact on overall energy use. However, existing parameters do not adequately capture these effects, so the new metrics developed in this paper are used to analyse the impact of thermal mass in hot climates with active cooling, and cold climates with active heating. The results agree with existing literature that high thermal mass structures are likely to be effective in hot climates; however, in cold climates the drawbacks of high thermal mass likely outweigh the advantages, and high thermal mass can cause an increase in energy use. This finding has implications for the design of buildings in cold climates, and contradicts the commonly-held assumption that high thermal mass is correlated with low energy use. The new metrics (transient energy ratio and effective U -value) provide a generalisable method to quantify these effects. They are further used here to analyse the dynamic performance of heavily insulated buildings and show that high thermal mass often leads to higher energy use in cold climates. [ABSTRACT FROM AUTHOR]

South East Europe is the region in a part of Europe with approximately 65.5 million inhabitants, making up 8.9% of Europe’s total population. The countries concerned have distinct geographical features, various climates and significant differences in gross domestic product per capita, so the integration of their energy systems is considered to be a challenging task. Large differences between energy mixes, still largely dominated by fossil-fuel consumption, make this task even more demanding. This paper presents the transition steps to a 100% renewable energy system which need to be carried out until the year 2050 in order to achieve zero carbon energy society. Novelty of this paper compared to other papers with similar research goals is the assumed sustainable use of biomass in the 100% renewable energy system of the region considered. It is important to emphasize here that only the sustainable use of biomass can be considered carbon-neutral. The resulting biomass consumption of the model was 725.94 PJ for the entire region, which is in line with the biomass potential of the region. Modelling the zero-carbon energy system was carried out using the smart energy system concept, together with its main integration pillars, i.e. power-to-heat and power-to-gas technologies. The resulting power generation mix shows that a wide variety of energy sources need to be utilized and no single energy source has more than a 30% share, which also increases the security of supply. Wind turbines and photovoltaics are the main technologies with shares of 28.9% and 22.5%, followed by hydro power, concentrated solar power, biomass (mainly used in cogeneration units) and geothermal energy sources. To keep the biomass consumption within the sustainability limits, there is a need for some type of synthetic fuel in the transportation sector. Nevertheless, achieving 100% renewable energy system also promises to be financially beneficial, as the total calculated annual socio-economic cost of the region is approximately 20 billion euros lower in the year 2050 than in the base year. Finally, energy efficiency measures will play an important role in the transition to the zero-carbon energy society: the model shows that primary energy supply will be 50.9% lower than in the base year. [ABSTRACT FROM AUTHOR]

Highlights • Taiwanese building energy conservation index (ENVLOAD) was converted to OTTV. • New models for energy efficient envelope were proposed as an adaption to the changing climate. • Coefficients of the OTTV model should be changed to reflect climate change. • Thermal insulation is gaining more concern while climate change proceeds. • Altering method of OTTV and setting new criteria in response to future climate was proposed. Abstract Changes in the climate system affect a building's energy consumption. Many countries have implemented building energy consumption indices to regulate the newly built buildings from excessive energy use. However, those indices were developed based on previous climate datasets and were incapable of responding to the changing climate. To stabilize the energy uses of future buildings as those under today's climate, regular updates of the evaluation index are mandatory to take climatic variations into consideration. This study firstly discussed the limitations in responding to future climate of current practicing building envelope energy conservation index in Taiwan. Secondly, we proposed a new index, the overall thermal transfer value (OTTV), based on the simulation results and tried to convert existing baseline criteria for the new OTTV. An approach on how to alter the OTTV index in response to the climate change was proposed. We found that because of the warming climate, the coefficient of the OTTV equation has to be changed over times to accurately respond to the changing climate. The approach presented in this paper provides a method on how to formulate a climate responsive index in pursuit of a better energy efficient building in the future. [ABSTRACT FROM AUTHOR]

Given the need to rein in the rise in the global average temperature, decarbonizing the electricity sector, which accounts for nearly 50% of global greenhouse gas (GHG) emissions, is crucial. The suitability of nuclear power as a base-load technology and its relatively negligible GHG emissions raised expectations of a nuclear renaissance, until the Fukushima disaster brought discussions about nuclear power’s potential to a standstill. However, completely ruling out nuclear may not be sustainable owing to the realities of rising energy demand, climate change considerations, and the need for reliable base-load supply technology, especially in the case of fast growing economies in the Association of South East Asian Nations (ASEAN). The Fukushima disaster was a wake-up call for both governments and the nuclear industry. Led by the International Atomic Energy Agency, the more advanced economies conducted stringent reviews of safety standards and emergency response procedures in the event of a catastrophe. Meanwhile the industry responded with strong commitments towards “Fukushima proof” designs, alongside other advancements towards “safer” fission power. In the ASEAN context, we argue in this paper that in addition to the economic advantage, nuclear power can help address the twin objectives of energy security and mitigating climate change effects. In ASEAN, there is still a strong momentum towards nuclear power development due to strategic considerations. In this paper, we reviewed in a holistic approach the various factors influencing decision making on nuclear power. Using ASEAN as a case study, we argue that nuclear power remains an important option and should be taken up rapidly if decarbonizing electricity generation is a grave concern. We also provide some recommendations towards the “safer nuclear” for ASEAN at the end of this paper. [ABSTRACT FROM AUTHOR]

Household fuel-use (HFU) patterns are strongly associated with multiple effects, including air quality, human health, and regional climate change. This paper presents the results from the first Chinese Environmental Exposure-Related Human Activity Patterns Survey (CEERHAPS), carried out among 91,121 households located in 9108 villages, 636 towns, and 159 counties in 31 provinces. Face-to-face interviews were conducted with each participant to obtain information about the type of fuels used for cooking and heating. The main objectives of this paper were to investigate HFU for cooking and heating in China, to validate the World Health Organization (WHO) model, and to help inform local evaluation models. In China, gas and biomass fuels, the dominant energy fuels for cooking, are used by 44.8% and 32.1% of households, respectively. Approximately 34.1% of families have no household heating during the cold season, and 16.7%, 15.6% and 12.8% of households rely on coal, electricity, and biomass, respectively, for household heating when no central heating was available. The proportion of households using solid fuels has generally decreased during the last two decades. Considerable spatial variation was evident in the HFU patterns for both cooking and heating. The data revealed that the predominant fuel for cooking was biomass (47.6%) in rural populations, whereas urban households were more likely to cook with gas (65.8%). In terms of heating, coal (21.4%) and biomass (19.0%) were the main fuels used in rural households, while electricity (23.6%) and coal (10.5%) were more commonly used in urban areas. The overall HFU results for cooking from this study were comparable to those predicted using the WHO model. We also developed models at the provincial level to estimate HFU for cooking and heating in China; it is expected that the model, if confirmed by future studies, could be used for future research on household air pollution, domestic human exposure and burden of disease. [ABSTRACT FROM AUTHOR]

Accurately understanding the real situation of China’s carbon emissions at the provincial level is not only crucial for realizing carbon mitigation in China, but also of great importance for tackling climate change on a global scale. This paper uses detailed energy consumption data subdivided within each fuel type and sector-specific emission factors, to calculate both direct and indirect energy-related CO 2 emissions for China’s provinces, and offers provincially-targeted policy proposals on emission reductions. The results uncover large divergences in calculation of provincial CO 2 emissions between production-based and consumption-based accounting approaches. Considering the large amount of interprovincial CO 2 emission transfers embodied in secondary energy deployment, the consumption-based accounting performs better in reflecting the actual features and responsibilities of carbon emissions in the provinces of China. From the consumption perspective, Shandong, Hebei, Jiangsu, Inner Mongolia, Guangdong, Henan, Liaoning and Shanxi contributed to the majority of China’s carbon emission growth during the period of 1996–2013, while Xinjiang, Sichuan, Anhui, Tianjin and Hunan were playing an increasingly important role. These two groups of provinces should be regarded as the key regions for national emissions abatement. Meanwhile, the energy industry was the top sectoral contributor to CO 2 emissions growth in most provinces, while service and household sectors made increasingly significant impacts on driving up provincial emissions. Together with ongoing efforts in the energy sector, the mitigation of CO 2 emissions in service and household sectors deserves much more attention, especially in the transportation and urban household sectors. Furthermore, the temporal trends of carbon emissions in various provinces, as well as their factor and sectoral driving forces, varied greatly with each other. Therefore, each of the provinces should formulate emission reduction policies according to their own situation, and target the key driving factors and sectors of carbon emissions at the current stage or in the near future. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method for spatiotemporal coordination of multienergy systems is proposed. • Virtual energy storage gain is calculated based on spectral analysis. • The hydropower regulation ability affects the virtual energy storage gain. • The optimal coordination range between multiple energy sources is obtained. Utilizing the spatial heterogeneity and climate periodicity of various available renewable energy sources can enhance the multienergy complementarity, which will further reduce the energy storage demand and contributes to the "virtual energy storage gain." In this paper, we propose a spatiotemporal coordination method based on spectral analysis for a wind-PV-hydropower system that targets the maximum virtual energy storage gain. The complementary effect of hydropower on wind and PV power can be seen as changes in the regulation ability resulting from the hydropower construction development as well as a decreased variance in the total system production output. This method is used to determine the optimal coordination distance of multiple energy sources that are matched over different periods representing typical climate variation. A case study in the Yalong River basin in China obtains the best range of hydropower bundling surrounding wind power and PV power stations under different hydropower construction planning scenarios, and it reveals that increased regulation capacity of hydropower will reduce the optimal coordination distance but can achieve more energy balance if both actual storage and virtual storage is accounted for. This approach can realize energy delivery with the optimal coordination distance to meet intensive and efficient development needs, which can provide guidance and support for the planning and construction of wind-PV-hydropower storage systems. [ABSTRACT FROM AUTHOR]

In this paper we address the problem of designing new energy-efficient static daylight devices that will surround the external windows of a residential building in Madrid. Shading devices can in fact largely influence solar gains in a building and improve thermal and lighting comforts by selectively intercepting the solar radiation and by reducing the undesirable glare. A proper shading device can therefore significantly increase the thermal performance of a building by reducing its energy demand in different climate conditions. In order to identify the set of optimal shading devices that allow a low energy consumption of the dwelling while maintaining high levels of thermal and lighting comfort for the inhabitants we derive a multi-objective optimization methodology based on Harmony Search and Pareto front approaches. The results show that the multi-objective approach here proposed is an effective procedure in designing energy efficient shading devices when a large set of conflicting objectives characterizes the performance of the proposed solutions. [ABSTRACT FROM AUTHOR]

Addressing climate change requires the efforts of all countries with common but differentiated responsibilities. The mitigation responsibilities one country takes greatly depends on its national emission inventories. As a good complement to the production-based accounting (PBA) principle, consumption-based accounting (CBA) principle has been widely concerned. However, few studies focus on emissions equity issues temporally and spatially. In this paper, we explore the characteristics of production-based and consumption-based CO 2 emissions for 14 major economies through multiple-dimension comparisons to get insight into the emissions equity comparisons among major emitters. In particular, four categories of economies with different dynamic features are divided based on their percentage differences between PBA and CBA emissions. Demographical and economic variables are additionally taken into consideration. The results indicate that France and Russia hold extreme characteristic on evaluating the emission difference between two principles, while China and Chinese Taiwan reveal uniquely increasingly larger gaps between two principle emissions. Besides, the per capita CBA emissions grows more prominently and possesses a more obviously positive correlation with their own per capita GDP which confirms that CBA principle is potentially attractive for estimating national emissions. [ABSTRACT FROM AUTHOR]

Abstract: Thermal energy loss in the process industry is a significant issue due to the high temperatures and multiple heat intensive processes involved. High-grade thermal energy is typically recovered within processes. However, lower grade heat is often rejected to the environment. The benefits of capturing and utilising low grade thermal energy are highly dependent on the qualities and properties of the heat in the waste streams. The temperature of the low grade heat stream is the most important parameter, as the effective use of the residual heat or the efficiency of energy recovery from the low grade heat sources will mainly depend on the temperature difference between the source and a suitable sink, e.g. another process or space heating/cooling. In general, the temperatures of these waste heat sources are too low to produce electricity and direct heat use will depend on whether potential user can be found. This paper presents past and current drivers for heat recovery studies. High and low grade heat sources are defined according to the viability of recovery within the processes. Firstly, high grade heat capture within the processes is reviewed. Then, the focus is on the potential for low grade heat capture outside of the original plant. The paper addresses the potential for low grade heat recovery with regard to new incentives and technological advances. Finally, different aspects which influence the decision making for low grade heat recovery in the process industry are discussed. It is concluded that organisational, financial and economic barriers might be overcome and benefits from a holistic vision could be gained with stronger governmental policy and regulation incentives. [Copyright &y& Elsevier]

Abstract: In this paper, an attempt is made to investigate the thermal and electrical performance of a solar photovoltaic thermal (PV/T) air collector. A detailed thermal and electrical model is developed to calculate the thermal and electrical parameters of a typical PV/T air collector. The thermal and electrical parameters of a PV/T air collector include solar cell temperature, back surface temperature, outlet air temperature, open-circuit voltage, short-circuit current, maximum power point voltage, maximum power point current, etc. Some corrections are done on heat loss coefficients in order to improve the thermal model of a PV/T air collector. A better electrical model is used to increase the calculations precision of PV/T air collector electrical parameters. Unlike the conventional electrical models used in the previous literature, the electrical model presented in this paper can estimate the electrical parameters of a PV/T air collector such as open-circuit voltage, short-circuit current, maximum power point voltage, and maximum power point current. Further, an analytical expression for the overall energy efficiency of a PV/T air collector is derived in terms of thermal, electrical, design and climatic parameters. A computer simulation program is developed in order to calculate the thermal and electrical parameters of a PV/T air collector. The results of numerical simulation are in good agreement with the experimental measurements noted in the previous literature. Finally, parametric studies have been carried out. Since some corrections have been down on thermal and electrical models, it is observed that the thermal and electrical simulation results obtained in this paper is more precise than the one given by the previous literature. It is also found that the thermal efficiency, electrical efficiency and overall energy efficiency of PV/T air collector is about 17.18%, 10.01% and 45%, respectively, for a sample climatic, operating and design parameters. [Copyright &y& Elsevier]

Data centers are approximately 50 times more energy-intensive than general buildings. The rapidly increasing energy demand for data center operation has motivated efforts to better understand data center electricity use and to identify strategies that reduce the environmental impact. This research is presented analytical approach to the energy efficiency optimization of high density data center, in a synergy with relevant performance analysis of corresponding case study. This paper builds on data center energy modeling efforts by characterizing climate and cooling system differences among data centers and then evaluating their consequences for building energy use. Representative climate conditions for four regions are applied to data center energy models for several different prototypical cooling types. This includes cooling system, supplemental cooling solutions, design conditions and controlling the environment of ICT equipment were generally used for each climate zone, how these affect energy efficiency, and how the prioritization of system selection is derived. Based on the climate classification and the required operating environmental conditions for data centers suggested by the ASHRAE TC 9.9, a dedicated data center energy evaluation tool was taken to examine the potential energy savings of the cooling technology. Incorporating economizer use into the cooling systems would increase the variation in energy efficiency among geographic regions, indicating that as data centers become more energy efficient, their locations will have an increasing effect on overall energy demand. The proposal for the most energy-optimized data center is given by each climate zone. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to allocate carbon dioxide (CO 2 ) emissions that result from fuel combusted to produce electricity and heat to the end-use sectors (industry, buildings, transport, and agriculture) where the electricity and heat are actually consumed. Attributing these indirect emissions to the appropriate sectors results in a very different picture of CO 2 emissions per sector than is seen when only direct emissions are characterized. With attribution to the demand side, the industrial and buildings sectors contribute the largest shares of CO 2 emissions globally. When indirect emissions are allocated to their respective end-use sectors, the buildings sector’s share of total emissions increases the most, from 9% (direct emissions only) to 31% (including indirect emissions), which reflects the large share of electricity and heat consumed in this sector. The share of CO 2 emissions attributable to the industrial sector also increases significantly, from 18% to 37%. These increased values include emissions from both electricity and heat used in end-use sectors, in contrast to the traditional accounting method, which allocates all electricity and heat emissions to the transformation and energy sector. Allocating these emissions to end-use sectors makes it possible to assess the full potential impact of demand reduction of electricity and heat use. This article is based on contributions to the Fifth Assessment Report of Working Group III of the Intergovernmental Panel on Climate Change. [ABSTRACT FROM AUTHOR]

The concentration of CO 2 in the atmosphere is increasing rapidly. CO 2 emissions may have an impact on global climate change. Effective CO 2 emission abatement strategies such as carbon capture and storage (CCS) are required to combat this trend. Compared with pre-combustion carbon capture and oxy-fuel carbon capture approaches, post-combustion CO 2 capture (PCC) using solvent process is one of the most mature carbon capture technologies. There are two main barriers for the PCC process using solvent to be commercially deployed: (a) high capital cost; (b) high thermal efficiency penalty due to solvent regeneration. Applying process intensification (PI) technology into PCC with solvent process has the potential to significantly reduce capital costs compared with conventional technology using packed columns. This paper intends to evaluate different PI technologies for their suitability in PCC process. The study shows that rotating packed bed (RPB) absorber/stripper has attracted much interest due to its high mass transfer capability. Currently experimental studies on CO 2 capture using RPB are based on standalone absorber or stripper. Therefore a schematic process flow diagram of intensified PCC process is proposed so as to motivate other researches for possible optimal design, operation and control. To intensify heat transfer in reboiler, spinning disc technology is recommended. To replace cross heat exchanger in conventional PCC (with packed column) process, printed circuit heat exchanger will be preferred. Solvent selection for conventional PCC process has been studied extensively. However, it needs more studies for solvent selection in intensified PCC process. The authors also predicted research challenges in intensified PCC process and potential new breakthrough from different aspects. [ABSTRACT FROM AUTHOR]

Energy sectors of all the countries around the world are faced with a big challenge: the energy transition under the imperative of continuous reduction of carbon dioxide emissions. The energy transition and the sustainability constraints pose a significant challenge for engineers, researcher and scientists developing new and clean energy-efficient technologies. Energy production and transformations, along with its storage, distribution and consumption, are achieved by utilising new and clean energy technologies, with the goal of the continuous increase of energy efficiency, the growth of renewable energy sources utilisation, the uninterrupted switch from fossil fuels to alternative energy sources, and the continued reduction of CO2 emissions. This editorial paper addresses the latest progress and the findings in research and developments in the sustainable energy technologies, energy and environment systems from selected papers of the conference on Sustainable Development of Energy, Water and Environment Systems held in 2019. [ABSTRACT FROM AUTHOR]

This paper studies the impact of weather variation on energy use by using 5-minutes interval weather–energy data obtained from two residential houses: house 1 is a conventional house with advanced efficiency features and house 2 is a net-zero solar house with relatively more advanced efficiency features. Our result suggests that energy consumption in house 2 is not as sensitive to changes in weather variables as the conventional house. On average, we find that a one unit increase in heating and cooling degree minutes increases energy use by about 9% and 5% respectively for house 1 and 5% and 4% respectively for house 2. In addition, our findings suggest that non-temperature variables such as solar radiation and humidity affect energy use where the sensitivity rates for house 2 are consistently lower than that of house 1. Furthermore our result suggests that the sensitivity of energy use to weather depends on the season and specific time of the day/night. [ABSTRACT FROM AUTHOR]

The change in climate has led to an interest in how this will affect the energy consumption in buildings. Most of the work in the literature relates to offices and homes. However, this paper investigates a supermarket in northern England by means of a multiple regression analysis based on gas and electricity data for 2012. The equations obtained in this analysis use the humidity ratio derived from the dry-bulb temperature and the relative humidity in conjunction with the actual dry-bulb temperature. These equations are used to estimate the consumption for the base year period (1961-1990) and for the predicted climate period 2030-2059. The findings indicate that electricity use will increase by 2.1% whereas gas consumption will drop by about 13% for the central future estimate. The research further suggests that the year 2012 is comparable in temperature to the future climate, but the relative humidity is lower. Further research should include adaptation/mitigation measures and an evaluation of their usefulness. [ABSTRACT FROM AUTHOR]

• An uncertainty propagation method was developed which captures climate uncertainties. • The method is applicable to cases where few future weather files can be developed. • The method can reduce computation requirements following a probabilistic approach. • The impact of equipment modernization using updated design day files is investigated. In the United States, buildings consume a significant portion of total energy use and contribute to carbon emissions. Therefore, evaluating their performance for sustainable design is critical. While building standards are updated frequently to improve building efficiency, the climate is changing and classical (deterministic) approaches to quantifying building energy use may not be accurate. Significant uncertainties exist in current models of future building performance. Probabilistic approaches to evaluate whole building performance and account for climate uncertainties require large input data of climate projections with detailed spatial and temporal resolution and considerable computational resources. This paper offers a four-step process to propagate climate uncertainties from future climate projections into building energy performance. The climate uncertainty propagation method consists of a combination of regression, distribution fitting and random sampling. It has the potential to capture climate uncertainties in building simulation tools and is applicable to cases where limited future weather files can be produced. In addition, we include the use of updated design day files in future building performance analysis. Design days drive equipment modernization impacting whole building energy use under climate change. The Department of Energy office reference buildings for Philadelphia climate conditions are used as the case study. The aim of this research is to generate a probabilistic model that captures future building energy performance trends where can be applicable to regions that have limited future hourly weather files to be incorporated into building simulation tools. The results of this paper are intended to promote a probabilistic approach to account for climate uncertainties and to provide guidance in analyzing buildings projected energy consumption under climate change. [ABSTRACT FROM AUTHOR]

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: The residential sector is recognized as a major energy consumer and thus a significant contributor to climate change. Rather than focus only on current energy consumption and the associated emissions, there is a need to broaden sustainability research to include full life cycle contributions and impacts. This paper looks at houses from the perspective of the ecological footprint (EF), a well-known sustainability indicator. Exemplifying single-detached houses of the early 20th century, the century-old REEP House (downtown Kitchener, Canada), together with its high performance energy retrofits, is examined in detail. This research combines material, energy and carbon emission studies. Its scope covers the life cycle of the house, including the direct and indirect consumption of material and energy, and concomitant carbon emissions during its stages of material extraction, transportation, construction, operation, and demolition. It is revealed that the REEP House had a typical impact on the environment when it was built, and, even though the renovations to improve energy efficiency by 80% introduce additional embodied environmental impacts, they are environmentally sound activities because the environmental payback period is less than 2years. [Copyright &y& Elsevier]

Abstract: This paper uses multivariate co-integration Granger causality tests to investigate the correlations between carbon dioxide emissions, energy consumption and economic growth in China. Some researchers have argued that the adoption of a reduction in carbon dioxide emissions and energy consumption as a long term policy goal will result in a closed-form relationship, to the detriment of the economy. Therefore, a perspective that can make allowances for the fact that the exclusive pursuit of economic growth will increase energy consumption and CO2 emissions is required; to the extent that such growth will have adverse effects with regard to global climate change. [ABSTRACT FROM AUTHOR]

Abstract: The increasing pressure resulting from the need for CO2 mitigation is in conflict with the predominance of coal in China’s energy structure. A possible solution to this tension between climate change and fossil fuel consumption fact could be the introduction of the carbon capture and storage (CCS) technology. However, high cost and other problems give rise to great uncertainty in R&D and popularization of carbon capture technology. This paper presents a real options model incorporating policy uncertainty described by carbon price scenarios (including stochasticity), allowing for possible technological change. This model is further used to determine the best strategy for investing in CCS technology in an uncertain environment in China and the effect of climate policy on the decision-making process of investment into carbon-saving technologies. [Copyright &y& Elsevier]

Abstract: In the present paper, thermal simulation software (IDA Indoor Climate and Energy, developed by EQUA, Sweden) was employed in order to evaluate the effect of different street canyon geometries and orientations on building cooling loads in a dry environment – Sede-Boqer, located in the Negev desert, Israel. A residential building was monitored from January to August 2006 to calibrate the thermal and energy simulations in summer, using diverse solar geometries and axis orientations as input data. Simulations were carried out using the local TMY, taking into account different aspect ratios (H/W): 0.33, 0.66, 1 and 2 and street axis orientations: east–west, north–south, northwest–southeast (parallel to prevailing wind) and northeast–southwest (perpendicular to prevailing wind). Results are shown in terms of energy consumption for cooling for each canyon configuration. From the obtained results, general recommendations can be traced for urban planning in arid regions, which could help promoting sustainable and energy-responsive buildings. [Copyright &y& Elsevier]

Abstract: Realistic time-resolved data on occupant behaviour, presence and energy use are important inputs to various types of simulations, including performance of small-scale energy systems and buildings’ indoor climate, use of lighting and energy demand. This paper presents a modelling framework for stochastic generation of high-resolution series of such data. The model generates both synthetic activity sequences of individual household members, including occupancy states, and domestic electricity demand based on these patterns. The activity-generating model, based on non-homogeneous Markov chains that are tuned to an extensive empirical time-use data set, creates a realistic spread of activities over time, down to a 1-min resolution. A detailed validation against measurements shows that modelled power demand data for individual households as well as aggregate demand for an arbitrary number of households are highly realistic in terms of end-use composition, annual and diurnal variations, diversity between households, short time-scale fluctuations and load coincidence. An important aim with the model development has been to maintain a sound balance between complexity and output quality. Although the model yields a high-quality output, the proposed model structure is uncomplicated in comparison to other available domestic load models. [Copyright &y& Elsevier]

Abstract: The European Directive on Energy Performance of Buildings (EPBD) imposes the adoption of measures for improving the energy efficiency in buildings. These measures should take into account the local weather conditions as well as internal thermal environment and cost-effectiveness. In this respect, Italy is a very interesting benchmark. For Northern Italy, the climatic context is particularly difficult to deal with cold winters and hot summers. The legislations are changing very rapidly, but has not fully adapted to the local context. The considered methodology still involves winter heating while summer cooling is addressed in incomplete and inadequate ways. The energy issue is addressed only partially as final energy consumption, but with little attention to LCA. Moreover, the belief that the buildings with high energy savings are too expensive, and therefore not attractive from economic point of view. For these reasons, it is very important to develop case studies to demonstrate the effectiveness of sustainable energy in architecture, according to a holistic approach. This paper describes a detailed techno–economic analysis for Borgo Solare project, an extremely advanced and innovative residential settlement designed on sustainable architecture concepts. One of the most innovative aspects of the project is that it is not just an experimental operation but Borgo Solare is a real urban district, which will be built without public funds and should be inhabited by common people. Excellent energy performance, therefore, must be accompanied by affordable market prices. The energy and economical analysis is presented taking into account also the embodied energy of the building. The results on the performance of a sample building (case study) of this settlement are reported, according to different construction standards: prior to EPBD, present from the EPBD and more efficient developed specifically for the project. It has been shown that using the better design practices and technologies the higher initial embodied energy in a low energy building could quickly paid back during its life span. The economic analysis, in the same way, evidences that higher initial investment in case of energy efficient building could become economically convenient during the life span of the building. This kind of analysis is essential to determine the actual sustainability of a building. [Copyright &y& Elsevier]

Abstract: In order to respond to climatic change, many efforts have been made to reduce harmful gas emissions. According to energy policies, an important goal is the implementation of renewable energy sources, as well as electrical and oil combustion savings through energy conservation. This paper focuses on an extensive review of the technologies developed, so far, for central solar heating systems employing seasonal sensible water storage in artificial large scale basins. Among technologies developed since the late 1970s, the use of underground spaces as an energy storage medium – Underground Thermal Energy Storage (UTES) – has been investigated and closely observed in experimental plants in many countries, most of them, as part of government programmes. These projects attempt to optimise technical and economic aspects within an international knowledge exchange; as a result, UTES is becoming a reliable option to save energy through energy conservation. Other alternatives to UTES include large water tanks and gravel–water pits, also called man-made or artificial aquifers. This implies developing this technology by construction and leaving natural aquifers untouched. The present article reviews most studies and results obtained in this particular area to show the technical and economical feasibility for each system and specifics problems occurred during construction and operation. Advantages and disadvantages are pointed out to compare both alternatives. The projects discussed have been carried out mainly in European states with some references to other countries. [Copyright &y& Elsevier]