scholarly journals Energy efficiency of a hybrid cable yarding system: A case study in the North-Eastern Italian Alps under real working conditions

2021 ◽  
Vol 52 (3) ◽  
Author(s):  
Alberto Cadei ◽  
Omar Mologni ◽  
Luca Marchi ◽  
Francesco Sforza ◽  
Dominik Röser ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Total Energy ◽  
Fuel Consumption ◽  
Electric Propulsion ◽  
Net Energy ◽  
Line System ◽  
Work Cycle ◽  
Cable Yarding ◽  
Cable Lines

In order to reduce greenhouse gas emissions, low emission or zero-emission technologies have been applied to light and heavyduty vehicles by adopting electric propulsion systems and battery energy storage. Hybrid cable yarders and electrical slack-pulling carriages could represent an opportunity to increase the energy efficiency of forestry operations leading to lower impact timber harvesting and economic savings thanks to reduced fuel consumption. However, given the limited experience with hybrid-electric systems applied to cable yarding operations, these assumptions remain uncertain. This study assessed an uphill cable yarding operation using a hybrid cable yarder and an active slack-pulling electric power carriage over thirty working days. A total of 915 work cycles on four different cable lines were analysed. Longterm monitoring using Can-BUS data and direct field observations were used to evaluate the total energy efficiency, total energy efficiency (%), and fuel consumption per unit of timber extracted (L/m3). The use of the electric-hybrid system with a 700 V supercapacitor to store the recovered energy made it possible to reduce the running time of the engine by about 38% of the total working time. However, only 35% to 41% of the Diesel-based mechanical energy was consumed by the mainline and haulback winches. Indeed, the remaining energy was consumed by the other winches of the cable line system (skyline, strawline winches and carriage recharging or breaking during outhaul) or dissipated by the system (e.g., by the haulback blocks). With reference to all work cycles, the highest net energy consumption occurred during the inhaulunload work element with a maximum of 1.15 kWh, consuming 70% of total net energy consumption to complete a work cycle. In contrast, lower energy consumption was recorded for lateral skid and outhaul, recording a maximum of 23% and 32% of the total net energy consumption, respectively. The estimated recovered energy, on average between the four cable lines, was 2.56 kWh. Therefore, the reduced fuel need was assessed to be approximately 730 L of fuel in the 212.5 PMH15 of observation, for a total emissions reduction of 1907 kg CO2 eq, 2.08 kg CO2 eq for each work cycle.

Energy Consumption Prediction of University Buildings in China and Strategies for Energy Efficiency Management

2015 ◽  
Author(s):  
Li-juan Qu ◽  
Li-nan Lei ◽  
Wei Chen ◽  
Jin-yuan Qian
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Total Energy ◽  
Ministry Of Education ◽  
Total Energy Consumption ◽  
Use Of Resources ◽  
Starting Point ◽  
Conservation Actions ◽  
Urban Rural ◽  
University Buildings

In 2007, Chinese Ministry of Education (MOE) and Ministry of Housing & Urban-Rural Development (MOHURD) carried out the Campus Resource Conservation Actions, in order to take full use of resources and to improve the energy efficiency. However, due to the large amounts of universities, the total energy consumption and the energy efficiency situation have no objective statistics. Taking modeling the energy consumption of university buildings as the starting point, this paper analyzes the characteristics of university buildings in China. Then, we do the prediction, trend and potential analysis of the total energy consumption in 2020. In addition, four strategies for energy efficiency management are carried out, which might be helpful for all the university managers and related departments.

scholarly journals Comparison of energy inputs and energy efficiency for maize in a long-term tillage experiment under Pannonian climate conditions

2021 ◽  
Vol 67 (No. 5) ◽  
pp. 45-52
Author(s):  
Gerhard Moitzi ◽  
Reinhard W. Neugschwandtner ◽  
Hans-Peter Kaul ◽  
Helmut Wagentristl
Keyword(s):  
Energy Efficiency ◽  
Total Energy ◽  
Fuel Consumption ◽  
Crop Production ◽  
Energy Input ◽  
Conservation Tillage ◽  
Energy Output ◽  
No Tillage ◽  
Tillage Systems ◽  
Total Energy Input

Sustainable crop production requires an efficient usage of fossil energy. This six-year study on a silt loam soil (chernozem) analysed the energy efficiency of four tillage systems (mouldboard plough 25–30 cm, deep conservation tillage 35 cm, shallow conservation tillage 8–10 cm, no-tillage). Fuel consumption, total energy input (made up of both direct and indirect input), grain of maize yield, energy output, net-energy output, energy intensity and energy use efficiency were considered. The input rates of fertiliser, herbicides and seeds were set constant; measured values of fuel consumption were used for all tillage operations. Total fuel consumption for maize (Zea mays L.) production was 81.6, 81.5, 69.5 and 53.2 L/ha for the four tillage systems. Between 60% and 64% of the total energy input (17.0–17.4 GJ/ha) was indirect energy (seeds, fertiliser, herbicides, machinery). The share of fertiliser energy of the total energy input was 36% on average across all tillage treatments. Grain drying was the second highest energy consumer with about 22%. Grain yield and energy output were mainly determined by the year. The tillage effect on yield and energy efficiency was smaller than the growing year effect. Over all six years, maize produced in the no-tillage system reached the highest energy efficiency.  

Energy Efficiency in Children With Myelomeningocele During Acute Use of Assistive Devices: A Pilot Study

2018 ◽  
Vol 35 (1) ◽  
pp. 57-75 ◽  
Author(s):  
Jennifer K. Sansom ◽  
Beverly D. Ulrich
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Pilot Study ◽  
Oxygen Uptake ◽  
Early Adulthood ◽  
Minimal Change ◽  
Assistive Devices ◽  
Assistive Device ◽  
Energy Requirements ◽  
Net Energy

Due to increased metabolic demands during walking, ∼50% of children with myelomeningocele transition to wheelchair use during adolescence/early adulthood. The purpose of our pilot study involving children with myelomeningocele was to determine: (a) energy expenditure needs during acute use of common assistive devices and (b) if walking poles are a feasible assistive device. Oxygen uptake was recorded for eight (5–12 years old) children in four conditions: independent, walker, crutches, and poles. Acute pole use did not significantly differ from independent walking net energy consumption or cost. Participants consumed more energy while walking with the walker than independently. Our pilot results suggest that (a) acute use of common assistive devices while walking increases energy consumption and cost versus independent and (b) poles are feasible assistive devices, resulting in slightly increased energy requirements. Poles may have provided “just enough” support with minimal change in energy requirements for our participants and, with practice, may enable children with myelomeningocele to remain community ambulators.

scholarly journals Effect of tillage systems on energy input and energy efficiency for sugar beet and soybean under Pannonian climate conditions

2021 ◽  
Vol 67 (No. 3) ◽  
pp. 137-146
Author(s):  
Gerhard Moitzi ◽  
Reinhard W. Neugschwandtner ◽  
Hans-Peter Kaul ◽  
Helmut Wagentristl
Keyword(s):  
Energy Efficiency ◽  
Sugar Beet ◽  
Fuel Consumption ◽  
Energy Input ◽  
Energy Use ◽  
Energy Intensity ◽  
Conservation Tillage ◽  
Energy Output ◽  
Net Energy ◽  
Use Efficiency

Sustainable cropping systems require efficient usage of fossil energy. This study performed on a long-term field experiment in the Pannonian Basis investigated the energy efficiency of four tillage systems (mouldboard plough (MP), deep conservation tillage (CT<sub>d</sub>), shallow conservation tillage (CT<sub>s</sub>) and no-tillage (NT)) for sugar beet and soybean production, taking fuel consumption, total energy input (made up of both direct and indirect inputs), crop yield, energy output, net-energy output, energy intensity and energy use efficiency into account. The input rates of fertiliser, chemical plant protection, and seeds were set constant across years; whereas measured values of fuel consumption were used for all tillage treatments. NT required a considerably lower energy input than MP and CT<sub>d</sub> as no fuel is needed for tillage and just slightly more fuel for additional spraying of glyphosate. Anyhow, the energy efficiency parameters did not differ between tillage treatments, as theses parameters were mainly determined by energy output, which was considerably higher than the energy input. However, year effects on the energy efficiency were observed for both crops. Nitrogen fertilisation and diesel fuel consumption were identified as the most energy-intensive inputs. Consequently, the energy input for sugar beet was higher than that for soybean, which was identified as a low-input crop. But sugar beet attained a more than 4 times higher net-energy output, a 2.5 times higher energy use efficiency, and an energy intensity for yield production of less than 3 times those of soybean.  

scholarly journals Energy Efficiency of Continuous Rye, Rotational Rye and Barley in Different Fertilization Systems in a Long-Term Field Experiment

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 229
Author(s):  
Gerhard Moitzi ◽  
Reinhard W. Neugschwandtner ◽  
Hans-Peter Kaul ◽  
Helmut Wagentristl
Keyword(s):  
Energy Efficiency ◽  
Total Energy ◽  
Energy Input ◽  
Energy Use ◽  
Energy Output ◽  
Winter Rye ◽  
Net Energy ◽  
Energy Productivity ◽  
Total Energy Input ◽  
Use Efficiency

A goal in sustainable agriculture is to use fossil energy more efficiently in crop production. This 60-year-old experiment on a silt loam chernozem investigated effects of fertilization (unfertilized control, mineral fertilizer (NPK) and farmyard manure (FYM)) and rotation (continuous winter rye (CR), winter rye in rotation (RR), spring barley in rotation (SB) on diesel fuel consumption, total energy input (made of both direct and indirect inputs), crop yield, energy output, net-energy output, energy intensity, energy productivity and energy use efficiency. The input rates of fertilizer, herbicides and seeds were set constant during the experiment. Soil tillage was done with a moldboard plough with subsequent combined seedbed preparation and seeding. The mean calculated total energy input was highest in NPK with 11.28 GJ ha−1 and lowest in the unfertilized control with 5.00 GJ ha−1. Total energy input for FYM was intermediate with 6.30 GJ ha−1. With energetic consideration of NPK nutrients in FYM the total energy input increased to the level of NPK. The share of the fertilizer energy on the total energy input was 49% for NPK. Fertilization with FYM and NPK increased yield and energy output considerably, especially of CR and SB which attained about doubled values. Crop rotation also increased the yield and energy output, especially of unfertilized rye, which attained values increased by about 75%. Fertilization with FYM resulted in the highest energy efficiency as the net-energy output, the energy productivity and the energy use efficiency were higher but the energy intensity was lower compared to unfertilized controls and NPK. When the nutrients in FYM were also energetically considered, the energy efficiency parameters of FYM decreased to the level of the NPK treatment. Crop rotation increased the energy efficiency of winter rye compared to the monoculture.

Analysis of Energy Consumption for Protected Grape Production System in China

2014 ◽  
Vol 1073-1076 ◽  
pp. 2468-2472
Author(s):  
Dong Tian ◽  
Jing Wang ◽  
Jian Ying Feng
Keyword(s):  
Renewable Energy ◽  
Energy Consumption ◽  
Total Energy ◽  
Energy Use ◽  
Survey Method ◽  
Net Energy ◽  
Average Yield ◽  
Energy Productivity ◽  
Energy Inputs ◽  
Use Efficiency

This study examines energy consumption of inputs and output used in protected grape production, and aims at to find relationship between energy inputs and yield in the major protected grape producing regions in China. For this purpose, the data were collected from 516 questionnaires which included 304 effective ones by questionnaire survey method. The results indicated that total energy inputs were 57697.84 MJha-1where the Chemical with (32.4%) and Fertilizer with about (21.1%) were the major energy consumers. About 53.4% of the total energy inputs used in protected grape production was indirect while 46.6% was direct. The non-renewable shared about 78% whereas the renewable energy did 22%. Average yield and energy consumption are calculated as 25367.22Kgha-1and 299333.2MJha-1. Energy use efficiency, energy productivity, specific energy and net energy were 5.18, 0.44 kgMJ-1, 2.27 MJkg-1and241635.36 MJha-1, respectively.

scholarly journals The Challenge of Greening the Existing Residential Buildings in the Egyptian Market Base Case

2018 ◽  
Vol 2 (3) ◽  
pp. 136
Author(s):  
Amr Soliman ElGohary ◽  
Shereen Omar Khashaba
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Total Energy ◽  
Residential Buildings ◽  
Clean Energy ◽  
Green Buildings ◽  
Current Situation ◽  
Existing Buildings ◽  
Total Energy Consumption ◽  
Residential Sector

Existing buildings are the massive percentage of the building stock, and therefore, are the key to improving efficiency; buildings account for an enormous share of the climate change crisis, and approximately 40% of the world total energy consumption (McArthur & Jofeh, 2015). The Egyptian stock of buildings includes about 12 million buildings. 60% of these buildings are residential. The final electricity consumption of the residential buildings in 2010 was 51370 GWh and increased in 2014 to reach 62441 GWh. Thus the share of total energy consumption was 18.8% in 2010 and increased to reach 21.55% in 2014 ("Technology Roadmap - Energy efficient building envelopes.", 2013). Therefore, the residential sector plays an important role in the mitigation of energy consumption crisis, which is expected to increase. The research field and initiatives in Egypt on the green buildings and green buildings retrofits are rare and, if existing, are weakly applied. Unlike in developed countries, there is a large research on building retrofits, e.g., the Residential Property Assessed Clean Energy (R-PACE) program and the weatherization assistance program (WAP) of the department of energy (DOE). Both are examples of the incentives to green building initiatives globally. This paper discusses the challenge of greening the existing residential buildings in Egypt by demonstrating an analysis of the motives and the barriers to applying green measures in the Egyptian market. The research methodology comprises the analytical-comparative method. In the analytical part; the paper identifies the current situation of the residential sector energy consumption in Egypt, and the benefits of greening existing buildings for tenants, investors, and owners. In the comparative part, the current situation of Egypt's Green Market Business Case is compared with the international one, discussing the challenge of greening the residential buildings. The paper summarizes the opportunities to improve the building energy efficiency, incentives, and policies that are developed to address significant financial and technical awareness to building efficiency. These policies will help enable critical market actors to make decisions to promote energy efficiency in existing buildings.

scholarly journals A water-energy balance application with adaptations to a brazilian water supply system

2021 ◽  
Vol 10 (10) ◽  
pp. e380101019039
Author(s):  
Matheus Gonçalves Silqueira ◽  
Fernando das Graças Braga da Silva ◽  
Alex Takeo Yasumura Lima Silva ◽  
Matheus David Guimarães Barbedo
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Energy Balance ◽  
Water Supply ◽  
Total Energy ◽  
Electric Energy ◽  
Pressure Control ◽  
Supply System ◽  
Water Supply System ◽  
Total Energy Consumption

According to the Alliance to Save Energy, between 2 % and 3 % of the total electric energy consumed in the world is used for water pumping in supply systems, with the consumption reduction potential through energy efficiency and conservation measures being estimated at 25 %. In Brazil, the water supply sector corresponds to 2.6 % of the total energy consumed in the country, with pumping systems being responsible for over 90 % of the total energy consumption. It is extremely common to find supersized facilities with pump motor sets operating outside their ideal points, with it being a common practice to perform flow and pressure control through the installation of valves. The use of reducing valves inserts unnecessary pressure drops into the hydraulic system, increasing energy consumption. The objective of this work is to present an energy balance of a study sector of the Autonomous Water and Sewage Service (AWSS) of a municipality in the south of Minas Gerais, Brazil, aiming to elucidate the electric energy consumption of the system and where the reduction in such consumption may occur. For this, we measured data such as the efficiency of the pump motor sets, calculated performance indicators and water loss indices, and applied the energy balance adapted. This work presents an application of a water-energy balance with adaptations to a Brazilian water supply system, under the perspective of the energy efficiency in lift station pump motor sets.

Energy Efficiency in Lighting for Historical Buildings: Case Study of the El Aman Caravanserai in Province of Bitlis, Turkey

2020 ◽  
pp. 68-76
Author(s):  
Behcet Kocaman
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
New Technologies ◽  
Light Emitting Diode ◽  
Metal Halide ◽  
Net Energy ◽  
Historic Buildings ◽  
Historical Buildings ◽  
The Cost ◽  
Metal Halide Lamps

Historical buildings are bridges between the past and the present. Moreover, it is a mirror of the life of societies, which lived in other ages. Historic buildings need to be illuminated to provide better visual conditions. The demand for electricity is increasing day by day. Energy must be used efficiently to reduce the amount of energy being dissipated. Therefore, energy efficiency in the lighting for historical buildings is a topic of great importance. Various luminaires are used for interior and exterior lighting of historic buildings. However, new lighting technologies, such as light emitting diode (LED) luminaires, are many times more efficient than traditional technologies, such as incandescent luminaires. The use of new technologies can lead to significant reductions in net energy consumption and associated reductions in greenhouse gas emissions. Historic buildings can serve as powerful and highly visible demonstrations of energy-efficient lighting technologies. In this study, the cost and energy efficiency have been analyzed considering the investment costs and the energy consumption of LED luminaires instead of luminaires with incandescent, halogen and metal halide lamps using almost the same luminous flux in the example of the El Aman Caravanserai in Bitlis, Turkey. As a result, of the calculations, the annual energy consumption (9-066.6 kW·h) was reduced by 78.21 % compared to the conventional system (41-610 kW·h) installed with incandescent, halogen and metal halide lamps. Thus, the cost of using LED lighting system have been amortised in about 135 days. Later, lighting has been made with less energy consumption, and the energy has been used efficiently.

A Study on Energy Consumption Optimization for Cooperative Beamforming in Wireless Sensor Networks

2014 ◽  
Vol 620 ◽  
pp. 625-631
Author(s):  
Guang You Yang ◽  
Xiong Gan ◽  
Tuo Zheng ◽  
Zhi Yan Ma
Keyword(s):  
Energy Efficiency ◽  
Wireless Sensor Networks ◽  
Energy Consumption ◽  
Sensor Networks ◽  
Total Energy ◽  
Wireless Sensor ◽  
Total Energy Consumption ◽  
Energy Consumption Optimization ◽  
Modulation Parameter ◽  
Cooperative Beamforming

In wireless sensor networks where the volume and energy of nodes are limited by batteries, which are difficult or prohibitively expensive to replace or recharge in the most of its application scenarios, so improving energy efficiency has very important significance.Cooperative beamforming forms virtual antenna arrays by multiple adjacent wireless sensor nodes, which improves the signal strength at the receiver and reduces the energy consumption of the transmitter by multiplexing gain and interference management.In this paper, the problem of energy consumption optimization for cooperative beamforming in wireless sensor networks was studied. First, considering both amplifier energy consumption and circuit energy consumption,energy consumption models for both broadcast phase and cooperative beamforming phase was presented.Then,we propose a two-step optimization to minimize the total energy consumption by optimizing the modulation parameter and the number of cooperative nodes.We simulate the total energy consumption for various transmission distances,modulation parameters , path losses and the number of cooperative nodes.The numerical results show that,for different system parameters, selecting the optimal modulation parameter and the optimal number of cooperative nodes can reduce total energy consumption and improve energy efficiency.

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