scholarly journals Energy Assessment of Pastoral Dairy Goat Husbandry from an Agroecological Economics Perspective. A Case Study in Andalusia (Spain)

2018 ◽  
Vol 10 (8) ◽  
pp. 2838 ◽  
Author(s):  
David Pérez-Neira ◽  
Marta Soler-Montiel ◽  
Rosario Gutiérrez-Peña ◽  
Yolanda Mena-Guerrero

This paper presents a methodological proposal of new energy sustainability indicators according to a novel accounting that follows agroecological and ecological economics criteria. Energy output is reformulated to include manure and thus consider the contribution to fertilization made by pastoral livestock farming to agroecosystems. Energy inputs calculations include the grazing resources. These new definitions and calculations allow for new formulations of the energy return on investment (EROI) as measures of the energy efficiency of livestock farming systems (final EROI and food/feed EROI). The environmental benefit of manure is estimated from the avoided energy cost of using this alternative to inorganic fertilizers (AECM). The environmental benefit of grazing is measured through the energy cost of avoiding cultivated animal feed (AECP) and its impact in terms of non-utilized agricultural area (ALCP). The comparative analysis of different livestock breeding systems in three pastoral dairy goat farms in the Sierra de Cádiz in Andalusia, southern Spain, reveals the analytical potential of the new energy sustainability indicators proposed, as well as the potential environmental benefits derived from territorial-based stockbreeding and, more specifically, grazing activities. Those benefits include gains in energy efficiency, a reduction of the dependence on non-renewable energy, and environmental costs avoided in terms of energy in extensive pastoral systems.

Symmetry ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1063 ◽  
Author(s):  
Horng-Lin Shieh ◽  
Fu-Hsien Chen

Energy efficiency and renewable energy are the two main research topics for sustainable energy. In the past ten years, countries around the world have invested a lot of manpower into new energy research. However, in addition to new energy development, energy efficiency technologies need to be emphasized to promote production efficiency and reduce environmental pollution. In order to improve power production efficiency, an integrated solution regarding the issue of electric power load forecasting was proposed in this study. The solution proposed was to, in combination with persistence and search algorithms, establish a new integrated ultra-short-term electric power load forecasting method based on the adaptive-network-based fuzzy inference system (ANFIS) and back-propagation neural network (BPN), which can be applied in forecasting electric power load in Taiwan. The research methodology used in this paper was mainly to acquire and process the all-day electric power load data of Taiwan Power and execute preliminary forecasting values of the electric power load by applying ANFIS, BPN and persistence. The preliminary forecasting values of the electric power load obtained therefrom were called suboptimal solutions and finally the optimal weighted value was determined by applying a search algorithm through integrating the above three methods by weighting. In this paper, the optimal electric power load value was forecasted based on the weighted value obtained therefrom. It was proven through experimental results that the solution proposed in this paper can be used to accurately forecast electric power load, with a minimal error.


Author(s):  
Chuanqi Wang ◽  
Junjie Qiao ◽  
Yijia Song ◽  
Qi Yang ◽  
Dazhi Wang ◽  
...  

Abstract Nitric oxide (NO) is one of the most crucial products in the plasma-based nitrogen fixation process. In this work, in-situ measurements were performed for quantifying the NO synthesis spatially in a warm air glow discharge, through the method of Mid-infrared quantum cascade laser absorption spectroscopy (QCL-AS). Two ro-vibrational transitions at 1900.076 cm-1 and 1900.517 cm-1 of the ground-state NO(X) were probed sensitively by the help of the wavelength modulation spectroscopy (WMS) approach to increase the signal/noise (S/N) level. The results show a decline trend of NO synthesis rate along the discharge channel from the cathode to the anode. However, from the point of energy efficiency, the cathode region is of significantly low energy efficiency of NO production. Severe disproportionality was found for the high energy consumption but low NO production in the region of cathode area, compared to that in the positive column zone. Further analysis demonstrates the high energy cost of NO production in the cathode region, is ascribed to the extremely high reduced electric field E/N therein not selectively preferable for the processes of vibrational excitation or dissociation of N2 and O2 molecules. This drags down the overall energy efficiency of NO synthesis by this typical warm air glow discharge, particularly for the ones with short electrode gaps. Limitations of further improving the energy cost of NO synthesis by variations of the discharge operation conditions, such as discharge current or airflow rate, imply other effective manners able to tune the energy delivery selectively to the NO formation process, are sorely needed.


1997 ◽  
Vol 8 (3) ◽  
pp. 207-225
Author(s):  
A.J. Griffiths ◽  
P.J. Bowen ◽  
B.J. Brinkworth ◽  
I.R. Morgan ◽  
A Howarth

The Sports and Recreation sector within the UK uses the equivalent of 3 millions tonnes of coal per year to supply the activities demanded by an ever increasing sports conscience society. The government has attempted to stimulate energy efficiency in this sector through the use of good practice guides and case studies. A comparative study was undertaken to analyse the performance of two leisure complexes in the Seven Valley degree day region. One site had double the occupancy rate of the other. It was found that the energy consumption per user was approximately 10 kWh for both sites. However the energy cost per user showed a large difference: for Site A this index was 31p/user compared to 15p/user at Site B. The primary causes of this difference are attributed to variation in energy mix between the two sites, as well as a difference in the price paid for primary fuel. Indices based on floor area of the facilities exhibit similar trends, and furthermore show that both sites were in the high band of energy consumption. This indicated that both sites had the potential to make significant energy-related savings, and a further breakdown of electrical, natural gas and water consumption per site is used to identify these potential savings in a rapidly expanding sector.


2021 ◽  
Vol 67 (No. 5) ◽  
pp. 45-52
Author(s):  
Gerhard Moitzi ◽  
Reinhard W. Neugschwandtner ◽  
Hans-Peter Kaul ◽  
Helmut Wagentristl

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.  


2021 ◽  
Vol 5 (1) ◽  
pp. 1-5
Author(s):  
Editorial team

Eurasian Journal of Physics and Functional Materials is an international journal published 4 numbers per year starting from October 2017. The aim of the journal is rapid publication of original articles and rewiews in the following areas: nuclear physics, high energy physics, radiation ecology, alternative energy (nuclear and hydrogen, photovoltaic, new energy sources, energy efficiency and energy saving, the energy sector impact on the environment), functional materials and related problems of high technologies.


Author(s):  
Heejin Cho ◽  
Sandra D. Eksioglu ◽  
Rogelio Luck ◽  
Louay M. Chamra

The Combined Cooling, Heating, and Power (CCHP) systems have been widely recognized as a key alternative for thermal and electric energy generation because of the outstanding energy efficiency, reduced environmental emissions, and relative independence from centralized power grids. Nevertheless, the total energy cost of CCHP systems can be highly dependent on the operation of individual components and load balancing. The latter refers to the process of fulfilling the thermal and electrical demand by partitioning or “balancing” the energy requirement between the available sources of energy supply. The energy cost can be optimized through an energy dispatch algorithm which provides operational/control signals for the optimal operation of the equipment. The algorithm provides optimal solutions on decisions regarding generating power locally or buying power from the grid. This paper presents an initial study on developing an optimal energy dispatch algorithm that minimizes the cost of energy (i.e., cost of electricity from the grid and cost of natural gas into the engine and boiler) based on energy efficiency constrains for each component. A deterministic network flow model of a typical CCHP system is developed as part of the algorithm. The advantage of using a network flow model is that the power flows and efficiency constraints throughout the CCHP components can be readily visualized to facilitate the interpretation of the results. A linear programming formulation of the network flow model is presented. In the algorithm, the inputs include the cost of the electricity and fuel and the constraints include the cooling, heating, and electric load demands and the efficiencies of the CCHP components. This algorithm has been used in simulations of several case studies on the operation of an existing micro-CHP system. Several scenarios with different operational conditions are presented in the paper to demonstrate the economical advantages resulting from optimal operation.


2021 ◽  
pp. 85-94
Author(s):  
Mohamed Elhoseny ◽  
◽  
◽  
X. Yuan

Energy efficiency is a significant challenge in mobile ad hoc networks (MANETs) design where the nodes move randomly with limited energy, leading to acceptable topology modifications. Clustering is a widely applied technique to accomplish energy efficiency in MANET. Therefore, this paper designs a new energy-efficient clustering protocol using an enhanced rain optimization algorithm (EECP-EROA) for MANET. The EROA technique is derived by integrating the Levy flight concept to the ROA to enhance global exploration abilities. In addition, the EECP-EROA technique intends to proficiently select CHs and the nearby nodes linked to the CH to generate clusters. Moreover, the EECP-EROA technique has derived an objective function with different input parameters. To showcase the superior performance of the EECP-EROA technique, a brief set of simulations takes place, and the results are inspected under varying aspects. The experimental values pointed out the betterment of the EECP-EROA technique over the other methods.


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