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Bioplastics are alternatives of conventional petroleum-based plastics. Bioplastics are polymers processed from renewable sources and are biodegradable. This study aims at conducting an environmental impact assessment of the bioprocessing of agricultural wastes into bioplastics compared to petro-plastics using an LCA approach. Bioplastics were produced from potato peels in laboratory. In a biochemical reaction under heating, starch was extracted from peels and glycerin, vinegar and water were added with a range of different ratios, which resulted in producing different samples of bio-based plastics. Nevertheless, the environmental impact of the bioplastics production process was evaluated and compared to petro-plastics. A life cycle analysis of bioplastics produced in laboratory and petro-plastics was conducted. The results are presented in the form of global warming potential, and other environmental impacts including acidification potential, eutrophication potential, freshwater ecotoxicity potential, human toxicity potential, and ozone layer depletion of producing bioplastics are compared to petro-plastics. The results show that the greenhouse gases (GHG) emissions, through the different experiments to produce bioplastics, range between 0.354 and 0.623 kg CO2 eq. per kg bioplastic compared to 2.37 kg CO2 eq. per kg polypropylene as a petro-plastic. The results also showed that there are no significant potential effects for the bioplastics produced from potato peels on different environmental impacts in comparison with poly-β-hydroxybutyric acid and polypropylene. Thus, the bioplastics produced from agricultural wastes can be manufactured in industrial scale to reduce the dependence on petroleum-based plastics. This in turn will mitigate GHG emissions and reduce the negative environmental impacts on climate change.

Abstract From model and case studies based on small samples it is clear that specific greenhouse gas (GHG) emissions of energy supply from biogas are strongly dependent of system characteristics and scope. We derive prescriptive statistics for the GHG balance of electricity production from agricultural biogas systems on the basis of a large audit data set. System boundaries include upstream processes, the production of energy crops (EC), the anaerobic digestion process, the storage of digestate, and the utilization of biogas in a combined heat-and-power-unit (CHPU). For our sample of 593 biogas systems the calculated specific CO2-equivalent-emissions of electricity fed into the public grid range from −1,730 to 821 g kWh−1 (mean value ± standard deviation: 307 ± 125 g kWh−1; interquartile range: 249–384 g kWh−1). For the sample as a whole, the mix of input materials on a mass basis consists of 58% EC and 42% animal manure (AM). With this mix, the substrate supply chain contributes 56.3% to the total GHG-emissions of the biogas systems. To fully compensate GHG-emissions from EC production by avoided emissions from AM storage, the ratio AM/EC would need to be increased about fivefold. This result shows that in order to be sustainable, a biogas system in agriculture needs to be understood more as a servicing function to farming rather than the purpose of farming. Other dominant sources of GHG-emissions are the methane slip from the CHPU, biogas losses and parasitic electricity demand.

The process energy demand and the environmental indicators of two carbon fiber reinforced plastic process chains have been investigated. More precisely, the impact of different production set-ups for a standard textile preforming process using bindered non-crimp fabric (NCF) and a material efficient 2D dry-fiber-placement (DFP) process are analyzed. Both 2D preforms are activated by an infrared heating system and formed in a press. The resin-transfer-molding (RTM) technology is selected for subsequent processing. Within a defined process window, the main parameters influencing the process energy demand are identified. Varying all parameters, a reduction of 77% or an increase of 700% of the electric energy consumption compared to a reference production set-up is possible, mainly depending on part size, thickness, and curing time. For a reference production set-up, carbon fiber production dominates the environmental indicators in the product manufacturing phase with a share of around 72–80% of the total global warming potential (GWP). Thus, the reduction of production waste, energy efficient carbon fiber production, and the use of renewable energy resources are the key environmental improvement levers. For the production of small and thin parts in combination with long curing cycles, the influence of the processing technologies is more pronounced. Whereas for a reference production set-up, only 10% (NCF–RTM) and 15% (DFP–RTM) of the total GWP are caused by the processing technologies, a production set-up leading to a high process energy demand results in a share of 40% (NCF–RTM) and 49% (DFP–RTM), respectively.

Abstract The horticultural industry consumes increasing amounts of energy and water contributing to greenhouse gas emissions and global warming. The aim of this study was to investigate the energy flow and the environmental impact of different tomato cultivation systems when renewable energy sources are implemented in the production chain. Seven scenarios including heated greenhouses and open-field crops, in Southern and Central Europe, were examined in order to identify potentials to reduce energy costs, greenhouse gas emissions and increase water use efficiency along the cultivation phase. The environmental impact category applied in this work (carbon footprint) is related to global warming potential, which includes the basic emitted greenhouse gases contributing to climate change and uses CO2 as reference gas (CO2-equivalents). Additionally, an energy flow indicator (cumulative energy demand) and an inventory flow indicator (water use), both relevant to climate change, agriculture and energy processes were determined to assess the different scenarios. The main results showed that annual carbon footprint values varied between 0.1 and 10.1 CO2-eq/kg tomato. Annual cumulative energy demand presented values from 0.8 to 160.5 MJ/kg tomato. Water use efficiency values ranged between 25.6 and 60.0 L/kg. Hotspots for all seven scenarios were determined, with fossil fuel consumption accounting for most of the environmental impact, where applicable. Open-field tomato cultivation presented lower greenhouse gas emissions and cumulated energy demand, however water use efficiency values were smaller than in greenhouse scenarios. In greenhouse production, the use of renewable energy sources and an increased marketable yield reduced their greenhouse gas emissions drastically, even to the levels of open-field cultivation.

Abstract We assessed whether increasing airflow with an electric fan is similarly effective as decreasing air temperature with air cooling (AC) in preventing heat-related reductions in productivity, and elevations in body temperatures and discomfort in a warm/humid indoor environment. In 48 experimental trials, we compared the reduction in the human heat stress response of sixteen participants during 135 min of intermittent arm ergometry at a fixed heart rate of 110 beats min−1, from a simulated tropical environment (HOT; 30 °C, 70%RH; wind °C, 70%RH, wind °C, 70%RH, wind = 4.2 m s−1). Cumulative work was similarly improved (+11%) by FAN compared to AC. Likewise, reductions in rectal temperature, thermal sensation, and thermal discomfort were similar with the two different cooling strategies. Sweat losses in the FAN trial were higher compared to AC but lower than HOT without fanning. In conclusion, fanning offers an effective method for alleviating thermal stress and preventing productivity losses for workers exposed to environmental heat. Moving air instead of chilling it may require a little more sweating, but it can save electricity and hence lower greenhouse gas emissions compared to AC.

Abstract Historic settlements are a type of architecture adapted to local climate and geographical environment. For hundreds of years, people have been living in them. Rich and precious scientific design concepts of these organic settlements, including the site selection, the layout, and the building materials, should be investigated extensively. To explore these concepts, different historic settlements will be presented and discussed, in terms of different design elements and urban planning forms, and through the use of computational fluid dynamics (CFD). This paper presents the strategic ideas and methodology of the study. As an illustrative case study, the ambient wind environment within the Shang-gan-tang village in China has been investigated quantitatively adopting CFD (computational fluid dynamics) techniques. The interactions between settlement selection, layout, landscape and ambient environment were evaluated. The sustainable urban planning experiences were then summarized for guiding the creation of sustainable modern human settlement suitable for people living for hundreds of years.

Abstract Environmental damage due to the emission of greenhouse gases from conventional coal-based power plants is a growing concern. Various carbon capture strategies to minimize CO2 emissions are currently being investigated. Unfortunately, the efficiency drop due to de-carbonization is still significant and the capture rate is limited. Therefore three future hard coal IGCC concepts are assessed here, applying emerging technologies and various carbon capture approaches. The advanced pre-combustion capture concept is based on hot gas clean-up, membrane-enhanced CO conversion and direct CO2 condensation. The concept reached a net efficiency of 45.1% (LHV), representing an improvement of 6.46% compared to the conventional IGCC base case. The second IGCC concept, based on post-combustion capture via calcination–carbonation loops, hot gas clean-up and oxygen membranes, showed a net efficiency of 45.87% (LHV). The third IGCC concept applies hot gas clean-up and combustion of the unconverted fuel gas using pure oxygen. The oxygen is supplied by an integrated oxygen membrane. The combination of IGCC and oxy-fuel process reached a net efficiency of 45.74% (LHV). In addition to their increased efficiency, all of the concepts showed significantly improved carbon capture rates up to 99%, resulting in virtually carbon-free fossil power plants.

Climate change is the 21st century's greatest threat to health. Anaesthesia is responsible for high levels of waste production, significant greenhouse gas emissions and extensive energy consumption. Our aim was to design an instrument to assess attitudes and knowledge among anaesthetists as well as their organisation's readiness for change regarding climate action.In 2020, the Provider Education and Evaluation Project (PEEP) questionnaire was sent to anaesthetists working at a university hospital, which contains 65 items in five areas: demographics, personal attitudes, organisational readiness, opportunities, and specific anaesthesiologic knowledge regarding climate action. Except for two open text questions, all questions were closed questions.104 anaesthetists responded to the survey (response rate 62%). Environmental protection and sustainability were important to all participants (100%). Most felt threatened by the ongoing climate crisis (94.2%). While most participants agreed that their employer had the financial or technological capacities and that sustainability targets were compatible with core business activities (approval >60% for all), they felt unprepared and stated that they had too little time to consider environmental aspects during daily routines (disapproval >60% for all). Furthermore, knowledge on topics such as ongoing efforts to tackle climate change or the climate footprint of drugs and medical products, was rather scarce.The PEEP questionnaire is an applicable and viable tool to assess anaesthetists' knowledge and attitudes towards climate change and organisational readiness for change. While participants care about the climate crisis, organisational readiness was low, especially when it comes to staff readiness (i.e., skills and knowledge) and cultural readiness (i.e., shared values). These aspects need to be considered in order to successfully implement a carbon neutral health care system.