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Every type of agricultural production is a burden for the natural environment. The paper’s objective is to assess the energy use efficiency, GHG emissions, and provide an economic analysis of buckwheat production for Central Europe (Poland). The analysis and comparison involved two production systems: low-input and high-input ones. The experiment involved three varieties of buckwheat, Panda, Volma, and Mancan. The yields for analysis were obtained from the field experiment which was set up in 3k-p fractional design was applied in two replications in which at the same time five factors were tested (A—variety, B—mineral fertilisation, C—sowing rate, D—weed control, E—growth regulator). A quartile was used as a statistical tool to select production systems. A high-input buckwheat production regime required, on average, 74.00% more energy than a low-input system. The total mean energy input for three varieties ranged from 7532.7 to 13,106.9 MJ ha−1 for low- and high-input systems, respectively. The results show that the energy use efficiency, specific energy, and net energy gain for the low-input system were on average 1.51, 9.6 MJ kg−1, and 3878.8 MJ ha−1, respectively, for the investigated varieties. For the high-input system, it was 1.35, 10.9 MJ kg−1, 4529.9 MJ ha−1, respectively. The total CO2 equivalent emissions during buckwheat production were higher for the high-input system than for the low-input system by more than 40%. The economic analysis demonstrated that the high-input system had better economic efficiency (without EU payment), 1.01 on average, than the low-input system, 1.07 on average. The international literature does not offer research on energy analysis for the production of common buckwheat and GHG emissions. The findings of this study demonstrate how the production systems affect energy and economic efficiency as well as GHG emissions. The authors suggest further research in Europe and globally, particularly on the energy use efficiency and GHG emissions in the production of common buckwheat, to verify the present results and improve production technologies (reduce inputs and costs).

Recently, many activities have been undertaken to reduce the negative impact of transport on the environment, e.g., using propulsion sources and consumed energy. Electric and hybrid vehicles are becoming more and more popular. Methods of measuring the emissivity of the means of transport as well as devices for determining measurements are being developed. This work presents an indicator method (IM) for determining the emissivity of road transport, while omitting the use of quite complicated and expensive research equipment. For typical road vehicles, it is possible to determine the emissivity means of transport, taking into account statistical data. The values of the indicators selected, based on statistical data analysis, were verified by comparing their values with the results of the actual emissivity of air pollutants. As part of the research work, the emissivity values of selected means of transport in a distribution company were determined using the IM method. The results were compared with the actual emissivity measurements. The method of indicative determination of emissivity makes it possible to estimate the initial emissivity level, knowing the type of vehicle and the distance performed as part of the transport work. Thanks to a simple and uncomplicated method, delivery planning can become more sustainable, and the selection of less emissive means of transport can contribute to reducing the negative impact of transportation on the environment.

Constructed in 1986, the Biosphere 2 Test Module has been used since the end of that year for closed ecological systems experiments. It is the largest closed ecological facility ever built, with a sealed variable volume of some 480 cubic meters. It is built with a skin of steel spaceframes with double-laminated glass panels admitting about 65 percent Photosynthetically Active Radiation (PAR). The floor is of welded steel and there is an underground atmospheric connection via an air duct to a variable volume chamber ("lung") permitting expansion and contraction of the Test Module's air volume caused by changes in temperature and barometric pressure, which causes a slight positive pressure from inside the closed system to the outside thereby insuring that the very small leakage rate is outward. Several series of closed ecological system investigations have been carried out in this facility. One series of experiments investigated the dynamics of higher plants and associated soils with the atmosphere under varying light and temperature conditions. Another series of experiments included one human in the closed system for three, five and twenty-one days. During these experiments the Test Module had subsystems which completely recycled its water and atmosphere; all the human dietary needs were produced within the facility, and all wastes were recycled using a marsh plant/microbe system. Other experiments have examined the capability of individual component systems used, such as the soil bed reactors, to eliminate experimentally introduced trace gases. Analytic systems developed for these experiments include continuous monitors of eleven atmospheric gases in addition to the complete gas chromatography mass spectrometry (GCMS) examinations of potable, waste system and irrigation water quality.

The aim of this study is to investigate the possibility of enhancing the gasification process using a pre-treated biomass that presents higher heating value, higher C/O ratio and less moisture content than untreated biomass. The aim is to assess the gasification parameters that can be modified in order to achieve the best performance of the gasification system. These research studies have been carried out in collaboration with the Centre RAPSODEE (UMR CNRS 5302, IMT Ecole de mines Albi-Carmaux, France) and the Free University of Bolzano (Italy). The torrefaction of standard pellets is realized using a lab scale rotary kiln unit at RAPSODEE. On the contrary, the gasification tests are carried out at the Free University of Bozen-Bolzano by means of a fixed bed open top gasifier. The tests of pellets torrefaction has been carried out at 250°C and 270°C with two repetitions in order to obtain about 60 kg of pellets for each torrefied condition. The used feedstock is a standard French pellets produced from sawdust of oak and beech following the standard EN 14961-2 (“Wood pellets for non-industrial use”). The pellets are characterized before and after the torrefaction pre-treatment. The gasifier used for the gasification tests is an open top pilot-scale gasifier placed at the Bioenergy and Biofuel Lab of the Free University of Bolzano. The plant is an open top downdraft system, where both gas and feedstock move downward as the reactions proceed. The main difference between un-treated and torrefied pellets is the moisture content. In addition, a slight increase in terms of carbon content and LHV and a slight decrease in terms of volatile matter are observed by moving from standard to torrefied pellets. The torrefied pellets seem to reach lower performances in terms of cold gas efficiency (CGE) and char yield with respect to the standard pellets. However, the trends in terms of ER and CGE suggest that moving toward higher values of ER, higher values of CGE could be reached independently of the material used. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 403-406

Extensive research demonstrates the importance of user practices in understanding variations in residential heating demand. Whereas previous studies have investigated variations in aggregated data, e.g., yearly heating consumption, the recent deployment of smart heat meters enables the analysis of households’ energy use with a higher temporal resolution. Such analysis might provide knowledge crucial for managing peak demand in district heating systems with decentralized production units and increased shares of intermittent energy sources, such as wind and solar. This study exploits smart meter heating consumption data from a district heating network combined with socio-economic information for 803 Danish households. To perform this study, a multiple regression analysis was employed to understand the correlations between heat consumption and socio-economical characteristics. Furthermore, this study analyzed the various households’ daily profiles to quantify the differences between the groups. During an average day, the higher-income households consume more energy, especially during the evening peak (17:00–20:00). Blue-collar and unemployed households use less during the morning peak (5:00–9:00). Despite minor differences, household groups have similar temporal patterns that follow institutional rhythms, like working hours. We therefore suggest that attempts to control the timing of heating demand do not rely on individual households’ ability to time-shift energy practices, but instead address the embeddedness in stable socio-temporal structures.

One of the most important parameters for developing Clean Development Mechanism (CDM) project proposals in the electricity sector (both supply and efficiency) is the standard electricity ‘grid emission factor’, which represents the carbon dioxide related to a megawatt hour of electricity supplied or saved on the grid. While there are detailed guidelines from the CDM Executive Board on how to calculate this emission factor, the values used in registered CDM projects in South Africa vary widely, both due to changes in the rules over time and also to misapplication of the rules. This paper shows how the application of the latest guidelines gives a ‘combined margin emission factor’ for South Africa of 0.957 tCO2/MWh in 2009/2010. The variation in emission factors in the literature, as well as the importance of reducing the transaction costs for South African project developers, points to the need for an official published grid emission factor from the CDM host country authority in South Africa, the Designated National Authority (DNA), within the Department of Energy.

Rising climate change issues are prompting engineers and scientists to focus more on improving renewable energy conversion systems [...]

The multiple uncertainties in a microgrid, such as limited photovoltaic generations, ups and downs in the market price, and controlling different loads, are challenging points in managing campus energy with multiple microgrid systems and are a hot topic of research in the current era. Microgrids deployed at multiple campuses can be successfully operated with an exemplary energy management system (EMS) to address these challenges, offering several solutions to minimize the greenhouse gas (GHG) emissions, maintenance costs, and peak load demands of the microgrid infrastructure. This literature survey presents a comparative analysis of multiple campus microgrids’ energy management at different universities in different locations, and it also studies different approaches to managing their peak demand and achieving the maximum output power for campus microgrids. In this paper, the analysis is also focused on managing and addressing the uncertain nature of renewable energies, considering the storage technologies implemented on various campuses. A comparative analysis was also considered for the energy management of campus microgrids, which were investigated with multiple optimization techniques, simulation tools, and different types of energy storage technologies. Finally, the challenges for future research are highlighted, considering campus microgrids’ importance globally. Moreover, this paper is expected to open innovative paths in the future for new researchers working in the domain of campus microgrids.