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In the context of climate change and rural revitalization, numerous solar photovoltaic (PV) panels are being installed on village roofs and lands, impacting the enjoyment of the new rural landscape characterized by PV panels. However, the visual acceptance of PV panels in rural areas of China is not yet fully understood. This study aims to identify and correlate three key influential factors that contribute to the acceptance and appreciation of PV panels in China’s rural settings. A quasi-experiment was conducted, incorporating diverse landscapes into six rural settings, each containing both the original landscape and PV panels. The findings demonstrated that the original rural landscape was significantly more scenic than PV panels, and factors contributing to the appreciation of traditional landscapes, such as nostalgia, played a vital role in rejecting PV panels. Conversely, renewable energy-related factors, such as economic stakes and moral desirability, were found to contribute to the acceptance of PV panels. This study contributes to the strategic planning and design of solar PV panels in rural landscapes, taking into consideration social acceptance and local contexts.

This study is concerned with Mozambique’s energy diplomacy. Its objectives are twofold: to advance and apply relevant theoretical concepts, while providing empirical insights into the drivers of risk propensity in energy diplomacy. Despite the increasing relevance of Africa as an alternative source of energy, and mounting empirical evidence of local strategies of regime security based on energy resources, scholarship on the interplay between energy and foreign policy as a strategy for regime security of energy-producing states in Africa remains scarce. Prospect theory postulates that decision makers engage in risky diplomatic behaviour when facing losses but, will be risk-averse when facing gains. The case of Mozambique is intriguing, however, as risk propensity in the energy sector sometimes appears to follow a logic contrary to prospect theory’s predictions, and to respond to objectives beyond the energy sector itself. The emerging question is: What determines risk propensity in Mozambique’s energy diplomacy? To answer this question, this thesis focuses on the case of hydroelectricity, specifically the 1984 Cape Town Tripartite Agreement on the Cahora Bassa hydroelectric dam and the 2007 Cahora Bassa reversion to Mozambique. I apply a qualitative research methodology and expand prospect theory by adding regime security as a condition variable, which allows for the examination of how situations and context relative to regime security affect Mozambique’s risk propensity in energy diplomacy. The main argument is that, although actual risk propensity emerges from within the energy sector, risk propensity in Mozambique’s energy diplomacy is driven by aversion to perceived losses relating to regime security. The study concludes that it is the quest for regime security, and the concomitant economic benefits for elites, that drives risk propensity in the energy sector, rather than the prospects of losses and/or gains relative to energy security.

Abstract In this paper, the effects of hydrogen blending radio and EGR rate on combustion and emission characteristics of a PFI gasoline engine with hydrogen direct-injection have been investigated by numerical modeling methods using a new generation of CFD simulation software CONVERGE. Results showed that compared with original engine, hydrogen direct-injection PFI gasoline engine had a better performance on combustion characteristics, but it also had a disadvantage of increasing NOx emissions. With the increase of hydrogen blending radio, combustion duration shortened and CA50 advanced and was closer to TDC. And CO and THC emissions decreased, however NOx emission increased. The variations of the combustion and emission characteristics followed by the increase of the EGR rate were exactly the opposite to the change of hydrogen blending radio. Considering both the combustion and emission characteristics, using moderate EGR rate (15%~20%) under high hydrogen blending radio (15%~20%) condition can realize the simultaneous improvement of combustion and emission performance.

Abstract The development of high-performance shape-stable phase change materials composites (ss-PCMCs) with enhanced thermal conductivity and high phase change enthalpy is of great importance for thermal energy storage. Herein, we report the creation of novel ss-PCMCs by incorporation of organic PCMs (1-hexadecanamine (HDA) and palmitic acid (PA)) into the biomass carbon aerogels (BCAs refer to sunflower receptacle spongy carbon aerogel (r-CA) and sunflower stem carbon aerogel (s-CA)) through a simple vacuum infusion. Due to their abundant porosity, light weight and high specific surface area, organic PCMs can be spontaneously loaded into BCAs with an ultrahigh loading rate of up to 1988 wt%. The obtained of PCM/BCAs composites show high phase change enthalpy of ranging from 207.9 kJ kg−1 to 271 kJ kg−1, in addition to their excellent thermal stability and recyclability, e.g., their phase change enthalpy nearly remains unchanged even after 50 times of melting/freezing cycles. The PCM/BCAs composites also show an enhanced thermal conductivity. Furthermore, the light-to-thermal conversion efficiency was found to be promising candidates for light-to-thermal energy storage applications on basis of their 75.6% for HDA/r-CA and 67.8% for HDA/s-CA, respectively, making them abundant resource, cost-efficiency, simple and scalable fabrication process.

AbstractGreenhouse gas emissions from fertiliser production are set to increase before stabilising due to the increasing demand to secure sustainable food supplies for a growing global population. However, avoiding the impacts of climate change requires all sectors to decarbonise by a very high level within several decades. Economically viable carbon reductions of substituting natural gas reforming with biomass gasification for ammonia production are assessed using techno-economic and life cycle assessment. Greenhouse gas savings of 65% are achieved for the biomass gasification system and the internal rate of return is 9.8% at base-line biomass feedstock and ammonia prices. Uncertainties in the assumptions have been tested by performing sensitivity analysis, which show, for example with a ±50% change in feedstock price, the rate of return ranges between −0.1% and 18%. It would achieve its target rate of return of 20% at a carbon price of £32/t CO2, making it cost competitive compared to using biomass for heat or electricity. However, the ability to remain competitive to investors will depend on the volatility of ammonia prices, whereby a significant decrease would require high carbon prices to compensate. Moreover, since no such project has been constructed previously, there is high technology risk associated with capital investment. With limited incentives for industrial intensive energy users to reduce their greenhouse gas emissions, a sensible policy mechanism could target the support of commercial demonstration plants to help ensure this risk barrier is resolved.

The current organization of water supply systems demands drinking standards for all the households’ usage of water. Few dual water systems, i.e., systems in which the quality of the water supplied is differentiated by types of use, exist but are mainly circumscribed to developing countries. Besides, bath and showers are so far considered as a potable use of water despite only drinking and cooking activities requiring the high-quality standards of potable water. The present work demonstrates how the principles of dual water systems can be incorporated into the sustainable concept of product-service system (PSS) using a dual water system of a municipal water supply treatment plant in France as a case study. The PSS is based on the water quality, and the bathing activity of households is considered with a dedicated standard for the first time. Two systems are considered, S1 and S2, supplied with the same raw water quality and treated with drinking (S1) bathing standards (S2). The quality parameters considered are total organic carbon (TOC) and turbidity (T) and the potential savings related to costs, material, and energy consumptions are assessed using EVALEAU as a process modeling tool. The treatment lines consisted of powdered activated carbon (PAC) addition, coagulation, flocculation, settling, and rapid sand filtration. Results show that material consumption can be reduced by 41% mainly through the decrease in chemical consumption associated with the change of requirement for the TOC parameter. On the opposite, energy consumption was found dependent on the water of volume treated rather than its quality leading to only marginal savings. The cost was decreased by 37% as a result of the reduction of the chemicals consumed.

Among the sufficiency, efficiency, and renewable frameworks for reducing energy use and energy-related carbon emissions, Building Energy Sufficiency (BES) is gaining attention from policy makers and engineers. Despite the significant role of the building sector in the success of national energy and climate plans, there is a lack of research on the drivers, technologies, and effective policy instruments required to achieve BES in the building operational phase. To fill this gap, this study presents a systematic review of the definition and paradigm of BES and concludes that BES should address both occupant demand and energy or emissions requirements simultaneously. The characteristics of occupant demand in building services are divided into four dimensions: time and space, quality and quantity, control and adjustment, and flexibility. Technical options regarding the building architecture, the envelope system, and the building energy system are reviewed. Finally, policy implications and recommendations are discussed. The multiple benefits and multidisciplinary nature of BES justify further research and accelerated policy implementation in developed and developing countries.

Abstract The redox flow battery (RFB) is among the most promising large-scale energy storage technologies for intermittent renewables, but its cost and cycle life still remain challenging for commercialization. This work proposes and demonstrates a high-performance, low-cost and long-life tin-bromine redox flow battery (Sn/Br RFB) with the Br-mixed electrolyte. The coulombic efficiency and energy efficiency of the Sn/Br RFB reach 97.6% and 82.6% at a high operating current density of 200 mA cm−2, respectively. The peak power density at 50% state-of-charge achieves 673 and 824 mW cm−2 at 15 and 35 °C, respectively, which is among the highest performance of hybrid RFBs. To address the Sn cross-contamination issue, a Sn reverse-electrodeposition method is demonstrated, and achieves in-situ capacity recovery as well as long cycle life. Moreover, the active material cost of the Br-mixed electrolyte is merely $54 kWh−1, while capital cost of the Sn/Br RFB is estimated to be as low as $193 kWh−1 for 4-hour electricity discharge, and expected to reduce to $148 kWh−1 at the optimistic scenario in the future. With high cell performance, in-situ capacity recovery and inexpensive active materials, the Sn/Br RFB is believed to offer a promising solution for massive electricity storage.