53 research outputs found

    The environmental footprint of transport by car using renewable energy

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    Replacing fossil fuels in the transport sector by renewable energy will help combat climate change. However, lowering greenhouse gas emissions by switching to alternative fuels or electricity can come at the expense of land and water resources. To understand the scale of this possible tradeoff we compare and contrast carbon, land and water footprints per driven km in midsize cars utilizing conventional gasoline, biofuels, bioelectricity, solar electricity and solar‐based hydrogen. Results show that solar‐powered electric cars have the smallest environmental footprints per km, followed by solar‐based hydrogen cars, and that biofuel‐driven cars have the largest footprints

    Land, water and carbon footprints of circular bioenergy production systems

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    Renewable energy sources can help combat climate change but knowing the land, water and carbon implications of different renewable energy production mixes becomes a key. This paper systematically applies land, water and carbon footprint accounting methods to calculate resource appropriation and CO 2eq GHG emissions of two energy scenarios. The ‘100% scenario’ is meant as a thinking exercise and assumes a complete transition towards bioenergy, mostly as bioelectricity and some first-generation biofuel. The ‘SDS-bio scenario’ is inspired by IEA's sustainable development scenario and assumes a 9.8% share of bioenergy in the final mix, with a high share of first-generation biofuel. Energy inputs into production are calculated by differentiating inputs into fuel versus electricity and exclude fossil fuels used for non-energy purposes. Results suggest that both scenarios can lead to emission savings, but at a high cost of land and water resources. A 100% shift to bioenergy is not possible from water and land perspectives. The SDS-bio scenario, when using the most efficient feedstocks (sugar beet and sugarcane), would still require 11–14% of the global arable land and a water flow equivalent to 18–25% of the current water footprint of humanity. In comparative terms, using sugar or starchy crops to produce bioenergy results in smaller footprints than using oil-bearing crops. Regardless of the choice of crop, converting the biomass to combined heat and power results in smaller land, water and carbon footprints per unit of energy than when converting to electricity alone or liquid biofuel

    in case of Uzavtosanoat stock company

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    Thesis(Master) --KDI School:Master of Public Policy,2015For the last decades within the automobile industry, it is vital that companies adequately compete for consumer sales. With the industry struggling due to the current economic conditions, as well as a push for environmental sustainability, companies have to come up with new competitive strategies. There are 6 major ways that a company can give themselves an advantage over others. They are cost, quality, service, brand, innovation, and convenience. The current research is focused on competitive issues in economy of Uzbekistan, in particularly, automobile industry of Uzbekistan. This report analyses recent automotive market and it competitiveness in Republic of Uzbekistan and outside of it, and shows how the development of the automotive industry influenced the economy’s productivity and growth. The study also contains conclusions related to improving competitiveness of products and suggestions for government of in UzbekistanmasterpublishedBunyod Muhammadnosirovich HOLMATOV

    Can crop residues provide fuel for future transport? Limited global residue bioethanol potentials and large associated land, water and carbon footprints

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    Bioethanol production from non-crop based lignocellulosic material has reached the commercial scale and is advocated as a possible solution to decarbonize the transport sector. This study evaluates how much presently used transport related fossil fuels can be replaced with lignocellulosic bioethanol using crop residues, calculates greenhouse gas emission savings, and determines lignocellulosic bioethanol's land, water, and carbon footprints. We estimate global bioethanol production potential from 123 crop residues in 192 countries and 20 territories under different environmental constraints (optimistic and realistic sustainable potentials) versus no constraints (theoretical potential) on residue availability. Previous studies on global bioethanol production potential from lignocellulosic material focused on one or few biomass feedstocks, and excluded (un)constrained residue availability scenarios. Our results suggest the global net lignocellulosic bioethanol output ranges from 7.1 to 34.0 EJ per annum replacing between 7% and 31% of oil products for transport yielding relative emission savings of 338 megatonne (Mt; 70%) to 1836 Mt (79%). Emission savings range from 4% to 23% of total transport emissions in the realistic sustainable versus theoretical potential. Land, water and carbon footprints of net bioethanol vary between potentials, countries/territories, and feedstocks, but overall exceed footprints of conventional bioethanol. Averaged footprints range between 0.14 and 0.24 m2 land per megajoule (MJ−1), 74–120 L water MJ−1, and 28–44 g CO2 equivalent MJ−1, with smaller footprints in the theoretical potential caused by the exclusion of secondary residues and low price of alternative biomass chains in the sustainable potential

    Building wall corner structures, its microclimate and seismic resistance

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    Widespread low-rise residential buildings with a seismically resistant concrete frame and brick infill walls have lower microclimate levels in cold seasons due to low temperatures on the inner wall corner surfaces.These temperatures are lower if there is a corner column. For Bishkek, this temperature is 4.6 °C lower than that for permissible microclimate, even when the external wall has the required 70 mm of mineral wool slab insulation. It is caused by the negative effect of the wall corner thermal bridge. This effect is determined by ArchiCAD 20 software packages by visualizing the temperature distribution in the cross-section of the corner, which needs an additional thermal insulation layer of 40 mm. Using the LiraSAPR 2013 software package, the authors reduced the square cross-section dimensions of the column by 40 mm to allow for that additional thermal insulation layer. The optimal width of this layer is determined for different options for the meeting angle of two external walls from 70° to 180°. For a typical 90° angle, an acceptable width is 860 mm. With this insulation, it is possible to achieve the required temperature at the corner. The authors eliminated the negative thermal effect of the corner by rounding it with cement-sand plaster. Using the isotherms, it was determined that the rounding radius of 300 mm allowed for equal temperatures on the corner and inner surface of the external walls. The achieved results show that the microclimate formed as in a room without external wall corners
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