scholarly journals Einfluss von Betonzusatzmitteln auf die Energieund CO2-Bilanz von Beton / Influence of superplasticizers on the energy- and CO2 -balance of concrete

1997 ◽  
Vol 3 (5) ◽  
pp. 457-468
Author(s):  
J.-M. Obrecht ◽  
R. Gälli ◽  
P. Zimmermann ◽  
F. Fallscheer
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Entire Life ◽  
Entire Life Cycle ◽  
Concrete Buildings ◽  
Concrete Properties ◽  
Concrete Production ◽  
Co2 Balance

Abstract The energy consumption and the C02 emissions during the production of two different concrete mixes with identical concrete properties were compared. The two concrete samples were prepared with and without the addition of a superplasticizer. Less energy was consumed and less C02 was emitted for the case of concrete production including a superplasticizer as compared to the case of concrete production without a superplasticizer. This is due to the fact, that when a superplasticizer is used, less cement is needed to produce concrete with the same properties as those of concrete without superplasticizers. However, the relatively small dijferences in the energy consumption and in the C02 emissions become insignificant, if the entire life cycle of a building is considered. Effects like durability and the need for maintenance are expected to have a much higher influence on the life cycle assessment of concrete buildings.

scholarly journals Life Cycle Assessment of Stationary Storage Systems within the Italian Electric Network

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2047
Author(s):  
Maria Leonor Carvalho ◽  
Andrea Temporelli ◽  
Pierpaolo Girardi
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Lithium Iron Phosphate ◽  
Storage Systems ◽  
Battery Life ◽  
Battery Cell ◽  
Entire Life ◽  
Entire Life Cycle ◽  
Cell Production ◽  
Electric Network

The introduction of stationary storage systems into the Italian electric network is necessary to accommodate the increasing share of energy from non-programmable renewable sources and to reach progressive decarbonization targets. In this framework, a life cycle assessment is a suitable tool to assess environmental impacts during the entire life cycle of stationary storage systems, i.e., their sustainability. A Li-ion battery (lithium–iron–phosphate (LFP), nickel–manganese–cobalt (NMC) 532, and NMC 622) entire life cycle assessment (LCA) based on primary and literature data was performed. The LCA results showed that energy consumption (predominantly during cell production), battery design (particularly binder choice), inventory accuracy, and data quality are key aspects that can strongly affect results. Regarding the battery construction phase, LFP batteries showed better performance than the NMC ones, but when the end-of-life (EoL) stage was included, NMC cell performance became very close to those of LFPs. Sensitivity and uncertainty analyses, done using the Monte Carlo methodology, confirmed that the results (except for the freshwater eutrophication indicator) were characterized by a low dispersion and that the energy mix choice, during the different battery life phases, was able to greatly influence the overall impact. The use of primary and updated data related to battery cell production, like those used in the present paper, was necessary to obtain reliable results, and the application to a European production line is an item of novelty of this paper.

scholarly journals Comparative Analysis of Environmental Impacts of Selected Products

2013 ◽  
Vol 13 (1) ◽  
pp. 19-22 ◽  
Author(s):  
A. Fedoryszyn ◽  
M. Brzeziński
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Environmental Impact ◽  
Environmental Impacts ◽  
Entire Life ◽  
Entire Life Cycle ◽  
Manufactured Products ◽  
Functional Features ◽  
The Subject ◽  
Cast Products

Abstract The purpose of the present study is to demonstrate that environmental impacts exerted by manufactured products throughout their entire life cycle are major aspects to be considered, alongside their functional features and cost-effectiveness. One of the available methods to evaluate environmental impacts is known to as the Life Cycle Assessment (LCA) method. The study summarises the reports from the literature on the subject of environmental impact assessment. In conclusions, the authors indicate the need for assessing the environmental impact of cast products made from conventional and newly introduced alloys.

scholarly journals Life-Cycle Assessment of Carbon Footprint of Bike-Share and Bus Systems in Campus Transit

2020 ◽  
Vol 13 (1) ◽  
pp. 158
Author(s):  
Sishen Wang ◽  
Hao Wang ◽  
Pengyu Xie ◽  
Xiaodan Chen
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Carbon Footprint ◽  
Co2 Emission ◽  
Raw Material ◽  
Transit System ◽  
Two Systems ◽  
Bus System ◽  
Bike Share

Low-carbon transport system is desired for sustainable cities. The study aims to compare carbon footprint of two transportation modes in campus transit, bus and bike-share systems, using life-cycle assessment (LCA). A case study was conducted for the four-campus (College Ave, Cook/Douglass, Busch, Livingston) transit system at Rutgers University (New Brunswick, NJ). The life-cycle of two systems were disaggregated into four stages, namely, raw material acquisition and manufacture, transportation, operation and maintenance, and end-of-life. Three uncertain factors—fossil fuel type, number of bikes provided, and bus ridership—were set as variables for sensitivity analysis. Normalization method was used in two impact categories to analyze and compare environmental impacts. The results show that the majority of CO2 emission and energy consumption comes from the raw material stage (extraction and upstream production) of the bike-share system and the operation stage of the campus bus system. The CO2 emission and energy consumption of the current campus bus system are 46 and 13 times of that of the proposed bike-share system, respectively. Three uncertain factors can influence the results: (1) biodiesel can significantly reduce CO2 emission and energy consumption of the current campus bus system; (2) the increased number of bikes increases CO2 emission of the bike-share system; (3) the increase of bus ridership may result in similar impact between two systems. Finally, an alternative hybrid transit system is proposed that uses campus buses to connect four campuses and creates a bike-share system to satisfy travel demands within each campus. The hybrid system reaches the most environmentally friendly state when 70% passenger-miles provided by campus bus and 30% by bike-share system. Further research is needed to consider the uncertainty of biking behavior and travel choice in LCA. Applicable recommendations include increasing ridership of campus buses and building a bike-share in campus to support the current campus bus system. Other strategies such as increasing parking fees and improving biking environment can also be implemented to reduce automobile usage and encourage biking behavior.

scholarly journals Impact of Cycle Time and Payload of an Industrial Robot on Resource Efficiency

Robotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 33
Author(s):  
Florian Stuhlenmiller ◽  
Steffi Weyand ◽  
Jens Jungblut ◽  
Liselotte Schebek ◽  
Debora Clever ◽  
...  
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Resource Efficiency ◽  
Life Cycle Costs ◽  
Gas Emissions ◽  
Cycle Times ◽  
The Individual

Modern industry benefits from the automation capabilities and flexibility of robots. Consequently, the performance depends on the individual task, robot and trajectory, while application periods of several years lead to a significant impact of the use phase on the resource efficiency. In this work, simulation models predicting a robot’s energy consumption are extended by an estimation of the reliability, enabling the consideration of maintenance to enhance the assessment of the application’s life cycle costs. Furthermore, a life cycle assessment yields the greenhouse gas emissions for the individual application. Potential benefits of the combination of motion simulation and cost analysis are highlighted by the application to an exemplary system. For the selected application, the consumed energy has a distinct impact on greenhouse gas emissions, while acquisition costs govern life cycle costs. Low cycle times result in reduced costs per workpiece, however, for short cycle times and higher payloads, the probability of required spare parts distinctly increases for two critical robotic joints. Hence, the analysis of energy consumption and reliability, in combination with maintenance, life cycle costing and life cycle assessment, can provide additional information to improve the resource efficiency.

A Life Cycle Assessment of Biofuel Produced From Waste Cooking Oil

2018 ◽  
Author(s):  
Sierra Spencer ◽  
Malia Scott ◽  
Nelson Macken
Keyword(s):  
Global Warming ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Waste Cooking Oil ◽  
Oil Refining ◽  
Soy Oil ◽  
Waste Oil ◽  
Cumulative Energy ◽  
Cooking Oil

Biofuels have received considerable attention as a more sustainable solution for heating applications. Used vegetable oil, normally considered a waste product, has been suggested as a possible candidate. Herein we perform a life cycle assessment to determine the environmental impact of using waste vegetable oil as a fuel. We present a cradle to fuel model that includes the following unit processes: soybean farming, soy oil refining, the cooking process, cleaning/drying waste oil, preheating the oil in a centralized heating facility and transportation when required. For soybean farming, national historical data for yields, energy required for machinery, fertilizers (nitrogen, phosphorous and potassium), herbicides, pesticides and nitrous oxide production are considered. In soy oil refining, steam production using natural gas and electricity for machinery are considered inputs. Preprocessing, extraction using hexane and post processing are considered. In order to determine a mass balance for the cooking operation, oil carryout and waste oil removal are estimated. During waste oil processing, oil is filtered and water removed. Data from GREET is used to compute global warming potential (GWP) and energy consumption in terms of cumulative energy demand (CED). Mass allocation is applied to the soy meal produced in refining and oil utilized for cooking. Results are discussed with emphasis on improving sustainability. A comparison is made to traditional fuels, e.g., commercial fuel oil and natural gas. The production of WVO as fuel has significantly less global warming potential but higher cumulative energy consumption than traditional fuels. The study should provide useful information on the sustainability of using waste cooking oil as a fuel for heating.

Comparative Life Cycle Assessment of Autoclaved Concrete Blocks and Fired Blocks in China

2018 ◽  
Vol 913 ◽  
pp. 1018-1026
Author(s):  
Yan Qiong Sun ◽  
Yu Liu ◽  
Su Ping Cui
Keyword(s):  
Sensitivity Analysis ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Data Quality ◽  
Human Health ◽  
Functional Unit ◽  
Cement Production ◽  
Terrestrial Ecotoxicity ◽  
Concrete Blocks

In this paper, a variety of blocks were grouped into the autoclaved blocks and fired blocks as far as the productive technology is concerned. In order to compare the life cycle impacts of the two kinds of the blocks, a life cycle assessment of two products on the functional unit 1m3 was carried out through the exploitation of mineral stage, transportation stage and the production of the blocks stage on the considering of the resource and energy consumption and the pollutant discharges. The results demonstrated that the fired blocks appeared to have less impact than autoclaved concrete blocks on human health, marine ecotoxicity toxicity and terrestrial ecotoxicity toxicity nearly 30%. The raw coal led to the serious impacts on the fossil depletion through the cement production stage of the autoclaved concrete blocks accounting for 45.86% and the gangue exploitation stage of the fired blocks accounting for 42.5%. Assessment of the data quality that the data was of pretty high or within the permission. The sensitivity analysis and contribution analysis assessment showed that the conclusion were robust.

Epoxidation of juvenile hormone was a key innovation improving insect reproductive fitness

2021 ◽  
Vol 118 (45) ◽  
pp. e2109381118
Author(s):  
Marcela Nouzova ◽  
Marten J. Edwards ◽  
Veronika Michalkova ◽  
Cesar E. Ramirez ◽  
Marnie Ruiz ◽  
...  
Keyword(s):  
Life Cycle ◽  
Juvenile Hormone ◽  
Reproductive Performance ◽  
Reproductive Fitness ◽  
Fitness Cost ◽  
Evolutionary Significance ◽  
Methyl Farnesoate ◽  
Entire Life ◽  
Entire Life Cycle ◽  
Key Innovation

Methyl farnesoate (MF) plays hormonal regulatory roles in crustaceans. An epoxidated form of MF, known as juvenile hormone (JH), controls metamorphosis and stimulates reproduction in insects. To address the evolutionary significance of MF epoxidation, we generated mosquitoes completely lacking either of the two enzymes that catalyze the last steps of MF/JH biosynthesis and epoxidation, respectively: the JH acid methyltransferase (JHAMT) and the P450 epoxidase CYP15 (EPOX). jhamt−/− larvae lacking both MF and JH died at the onset of metamorphosis. Strikingly, epox−/− mutants, which synthesized MF but no JH, completed the entire life cycle. While epox−/− adults were fertile, the reproductive performance of both sexes was dramatically reduced. Our results suggest that although MF can substitute for the absence of JH in mosquitoes, it is with a significant fitness cost. We propose that MF can fulfill most roles of JH, but its epoxidation to JH was a key innovation providing insects with a reproductive advantage.

Rice metabolic regulatory network spanning its entire life cycle

2021 ◽  
Author(s):  
Chenkun Yang ◽  
Shuangqian Shen ◽  
Shen Zhou ◽  
Yufei Li ◽  
Yuyuan Mao ◽  
...  
Keyword(s):  
Life Cycle ◽  
Regulatory Network ◽  
Entire Life ◽  
Entire Life Cycle

Assessment of driving quality and its impact on changes in the technical condition of self-driving cars

2020 ◽  
pp. 24-26
Keyword(s):  
Artificial Intelligence ◽  
Life Cycle ◽  
Computer Technology ◽  
Technical Condition ◽  
Entire Life ◽  
Entire Life Cycle ◽  
Machine Maintenance ◽  
Current Task ◽  
Self Driving Cars

The article describes the current task of developing and improving existing technologies for machine maintenance throughout the entire life cycle. The use of modern achievements in the field of computer technology, digitization of information, as well as the development of artificial intelligence technologies, will allow you to get new scientific and engineering results aimed at managing the technical condition of machines in operation.

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