cumulative energy
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2024 ◽  
Vol 84 ◽  
Author(s):  
F. Ali ◽  
F. Rehman ◽  
R. Hadi ◽  
G. Raza ◽  
N. Khan ◽  
...  

Abstract Life cycle assessment was carried out for a conventional wooden furniture set produced in Mardan division of the Khyber Pakhtunkhwa province of Pakistan during 2018-19. Primary data regarding inputs and outputs were collected through questionnaire surveys from 100 conventional wooden furniture set manufacturers, 50 in district Mardan and 50 in district Swabi. In the present study, cradle-to-gate life cycle assessment approach was applied for a functional unit of one conventional wooden furniture set. Production weighted average data were modelled in the environmental impacts modelling software i.e., SimaPro v.8.5. The results showed that textile used in sofa set, wood preservative for polishing and preventing insects attack and petrol used in generator had the highest contribution to all the environmental impact categories evaluated. Total cumulative energy demand for wooden furniture set manufactured was 30,005 MJ with most of the energy acquired from non-renewable fossil fuel resources.


2022 ◽  
Vol 9 ◽  
Author(s):  
Zhengdian Xu ◽  
Hong Li ◽  
Yue Jiang ◽  
Qingjiang Xiang ◽  
Pan Tang

To solve the problems of higher energy consumption and lower intelligence of traditional hard hose travelers, a new hard hose traveler with the function of electric drive and self-propelled is developed in this paper. The operational energy consumption of a reel and a polyethylene tube is an important part of hard-hose traveler energy consumption. In this paper, based on the JP50-180 hard hose traveler, the required pulling force and energy consumption at the reel and tube operation are theoretically and experimentally obtained. The aforementioned provides support for reducing energy consumption in the future. The influencing factor that affects the energy consumption of the reel rotation is the tube length, and the influencing factors that affect the energy consumption of the tube sliding are the ground slope, soil moisture content, and tube length. A calculation model for the dynamic change of the pulling force and energy consumption of the reel and tube operation is proposed in this study. Through theoretical analysis, maximum pulling tension and cumulative energy consumption requirements for the for reel rotation are 278.6 N and 15120.83 J, respectively. Furthermore, the requirements for the tube sliding are 1372.86 N and 123,456.96 J. Through test analysis, the maximum pulling tension for the tube sliding is between 1258.3 N and 1773.3 N, while the maximum pulling tension for reel rotation is 285.05 N. Under the same influencing factors, the deviation rates between theoretical and testable energy consumption for the reel rotation and tube sliding are 2.3 and 8.3%, respectively. The pulling force and cumulative energy consumption required for the reel rotation and tube sliding both increase with an increase in their influencing factors. The operating costs of the tube one-time unrolled are approximately 0.0185 CNY. Combined with the mobile resistance of the electric tracked vehicle, the power configuration of this new hard hose traveler is provided by two servo motors with a power of 5500 W each.


Author(s):  
Nam-Chol O ◽  
Tong-Hyok Choe ◽  
Jong-Hun Kim ◽  
Chol-Mu Choe

A life cycle assessment of waste management in Pyongyang, Korea was undertaken using a characterisation-based method to analyse cumulative energy demand and energy-related carbon dioxide emissions. The study showed that characterising waste fractions by composition, proportion, water content and heating value rather than simply mass was more effective for energy-related analysis in life-cycle assessments. The results indicated that the energy demand and emissions indicators could be used as appropriate proxies of the environmental impacts in life-cycle phases, since they were closely related. The results also revealed that waste incineration could result in energy credit to the national electricity mix, while waste landfill needed to be replaced with sanitary landfill and/or switched to incineration with energy recovery to be more sustainable.


2022 ◽  
pp. 127-164
Author(s):  
Abdelmadjid Recioui ◽  
Fatma Zohra Dekhandji

The conventional energy meters are not suitable for long operating purposes as they spend much human and material resources. Smart meters, on the other hand, are devices that perform advanced functions including electrical energy consumption recording of residential/industrial users, billing, real-time monitoring, and load balancing. In this chapter, a smart home prototype is designed and implemented. Appliances are powered by the grid during daytime, and a photovoltaic panel stored power during the night or in case of an electricity outage. Second, consumed power from both sources is sensed and further processed for cumulative energy, cost calculations and bill establishment for different proposed scenarios using LABVIEW software. Data are communicated using a USB data acquisition card (DAQ-USB 6008). Finally, a simulation framework using LABVIEW software models four houses each equipped with various appliances. The simulator predicts different power consumption profiles to seek of peak-demand reduction through a load control process.


2021 ◽  
Vol 16 (2) ◽  
pp. 207-215
Author(s):  
Cheah Saw Kian ◽  

Optimal nutritional therapy is important to improve outcome in critically ill population in an intensive care unit (ICU). Although indirect calorimetry (IC) is currently a gold standard for resting energy expenditure (REE) measurement, yet it is still not routinely used in the ICU. A total of 146 mechanically ventilated patients were randomised to receive enteral nutrition (EN) with energy targeted based on continuous indirect calorimetry (IC) measurements (IC group, n=73) or according to 25 kcal/kg/day (SWB group, n=73). Patient characteristics were equally distributed and the IC group showed lower mean measured REE (1668.1 + 231.7 vs 1512.0 + 177.1 kcal, p<0.001). Results also showed a significant deficiency in the daily (-148.8 + 105.1 vs. -4.99 + 44.0 kcal, p<0.001) and total cumulative energy balances (-1165.3 + 958.1 vs. 46.5 + 369.5 kcal, p<0.001) in the SWB group as compared to the IC group. From the Kaplan-Meier survival analysis, we found that ICU mortality was significantly lower in the IC group with better survival probability compared to the SWB group (log-rank test, p = 0.03). However, both groups showed comparable results in terms of ICU length of stay, duration of mechanical ventilation and incidence of feeding intolerance. In conclusion, this study showed that tightly supervised nutritional therapy based on continuous IC measurement provides significantly less mean daily and cumulative energy deficits as well as significantly reduced ICU mortality rate.


Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8584
Author(s):  
Witold Jan Wardal ◽  
Kamila Ewelina Mazur ◽  
Kamil Roman ◽  
Michał Roman ◽  
Marcin Majchrzak

The increasing popularity of automated systems and the increased market share of producers of robotic feeding equipment for cows causes the need for a deeper study of energy demand in such technologies. This article provides an analysis of the inputs of energy accumulated in conventional (CFS) and automated feeding systems (AFS) for cattle. The aim of this is to determine the impact of robotic technologies for the preparation and feeding of fodder on the cumulative energy inputs. The aim of this paper is to investigate the effect of machinery and the equipment applied to the cumulative energy intensity in cattle farming facilities. The cumulative energy consumption for four technologies of automated cattle feeding (AFS) was tested and compared to the energy consumption for six technologies with a conventional feeding system (CFS). The research involved nine cow barn facilities for dairy cows and one for beef cattle. An evaluation has been made for cattle farming structures (milk and meat production) with various mixing and feeding systems for feeds of various concentrations, and keeping system (tied system and free-stall). The cow barns differed in feed mixing, feeding machinery, and equipment. Measurements of live labor inputs and the consumption of electric and mechanical energy carriers were carried out, and the mass of various types of machines and devices with software was taken into account, which became the basis for calculating cumulative energy consumption for individual technologies. The obtained average of electric and mechanical energy inputs for robotic technologies of feeding fodder (AFS) was 0.60025 kWh∙day−1∙LU−1(where LU means Large Animal Unit 500 kg), and it was 39.3% lower than for conventional technologies (CFS) where it was 0.989052 kWh∙day−1∙LU−1. However, taking into account all components of cumulative energy consumption, the average for the group of robotic technologies (AFS) was higher by 35.18% than for conventional technologies (CFS).


2021 ◽  
Vol 13 (24) ◽  
pp. 13878
Author(s):  
Hannah Porter ◽  
Abhijit Mukherjee ◽  
Rabin Tuladhar ◽  
Navdeep Kaur Dhami

Microbially Induced Calcium Carbonate Precipitation (MICP) is a natural biocementation that takes place in corals, stromatolites and beach rocks. In recent years, researchers have explored the emulation of this process as a sustainable alternative of engineered cement. Although the natural process is undoubtedly sustainable, its engineered variant deviates substantially from the natural process. In this paper, we investigate the environmental and economic performance of the engineered biocementation process vis-à-vis present manufacturing of calcium carbonate. SimaPro 8.0 software and the Ecoinvent V2.2 database were used for materials inputs and AUSLCI along with Cumulative Energy Demand 2.01 software were used for carbon footprint and eutrophication potential. Our results show that different metabolic pathways of MICP have considerably varying environmental impact. We observe that nature performs MICP sustainably at ambient conditions and geological time scales utilizing naturally occurring sources of carbon and calcium at micromoles concentrations. Due to the mandate on duration of construction projects, highly purified reactants in a high concentration are used in the engineered process. This has a negative environmental impact. We conclude that the sustainability of engineered MICP is directly impacted by the metabolic pathway of bacteria as well as the purity of the input chemicals. A few biotic processes are superior to the present industrial process for manufacturing calcium carbonate if ingredients of laboratory grade purity are replaced by industrial grade products. A bigger dividend can be obtained by introducing industry by-products as nutrients. The results of this study help to direct future research for developing sustainable biocement for the construction industry.


2021 ◽  
Vol 63 (12) ◽  
pp. 727-733
Author(s):  
A H Abdulaziz ◽  
J McCrory ◽  
K Holford ◽  
A Elsabbagh ◽  
M Hedaya

Due to their complexity, detecting and analysing damage modes in composite honeycomb sandwich panels can be difficult. This article describes the way in which a three-point bending test (3PBT) was performed on a glass fibre aluminium honeycomb sandwich panel (HSP). Acoustic emission (AE) was used to identify damage signals, which were then analysed to determine the positions and characteristics of defects. To locate damage positions, Delta-T mapping was used. The test load was progressively applied in three phases, with the specimen being inspected visually during each phase. A scanning electron microscope (SEM) showed that the most significant damage was local crushing under the test load, which caused matrix cracking, fibre breakage and pull-out. Damage progression and the damage mode were detected using the cumulative energy and frequency spectra of the AE sources for each phase. Matrix cracking frequencies ranged from 30 kHz to 100 kHz, while fibre damage modes ranged from 157 kHz to 322 kHz. The findings highlighted the utility of Delta-T mapping in locating damage positions on sandwich structures under testing. The investigation also emphasised the value of studying frequency spectra and cumulative energy when analysing AE signals.


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