scholarly journals Sustainable Protected Cropping: A Case Study of Seasonal Impacts on Greenhouse Energy Consumption during Capsicum Production

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4468 ◽  
Author(s):  
Premaratne Samaranayake ◽  
Weiguang Liang ◽  
Zhong-Hua Chen ◽  
David Tissue ◽  
Yi-Chen Lan

Sustainable food production in protected cropping is increasing rapidly in response to global climate change and population growth. However, there are significant knowledge gaps regarding energy consumption while achieving optimum environmental conditions for greenhouse crop production. A capsicum crop cultivated in a high-tech greenhouse facility in Australia was analysed in terms of relationships between key environmental variables and the comparative analysis of energy consumption during different seasons. We showed that daily energy consumption varied due to the seasonal nature of the external environment and maintenance of optimal growing temperatures. Total power consumption reported throughout the entire crop cycle for heating (gas hot water system) and cooling (pad and fan) was 12,503 and 5183 kWh, respectively; hence, heating consumed ca. 70% of the total energy requirement over the 8-month growing period (early spring to late autumn) in the greenhouse facility. Regressions of daily energy consumption within each season, designated either predominantly for heating or cooling, indicated that energy consumption was 14.62 kWh per 1 °C heating and 2.23 kWh per 1 °C cooling. Therefore, changing the planting date to late spring is likely to significantly reduce heating energy costs for greenhouse capsicum growers in Australia. The findings will provide useful guidelines to maximise the greenhouse production of capsicum with better economic return by taking into consideration the potential optimal energy saving strategy during different external environment conditions and seasons.

Author(s):  
Tran Hoang Vu ◽  
Vu Cong Luc

In  this  paper,  we  present  a  design  and  an evaluation  of  two  power  management  modes  that reduce the  energy  consumption  of OpenFlow switches. First,  we  define  two  new  low  power  modes:  SLEEP PORT  and  SLEEP  SWITCH,  which  reduce   energy consumption   in  cases  where  packets  on  port  or switches  are  absent.  Second,  we  present  a  Wake  on LAN  (WOL)  method  for  OpenFlow  Switches  to  wake up  Ethernet  ports  or  the  whole  switch  from  inactive states.  Finally,  we  describe  our  design,  experimental results and  performance evaluations. Our results show that the control SLEEP PORT mode on a switch might save  about 9.8% power consumption per  port,  and  up to about 60% of total power consumption of the switch with SLEEP  SWITCH mode.  In  addition,  we  will implement  this  method  to  Openflow  Switch  bases  on NetFPGA- 10 Gigabit in the future.


2018 ◽  
Vol 11 (4) ◽  
pp. 209-218
Author(s):  
RAJESH U. MODI ◽  
MUDASIR ALI ◽  
RAGHUVIRSINH P. PARMAR ◽  
SHARAD KUMAR NAMDEV

This computer application deals with energy auditing for rice-wheat cropping system. Computing different input parameters for the crop production system in terms of energy requirement (MJ/ha) can be done by using this computer application. The developed application was found to be a simple, easy and user-friendly with appropriate output units. It works efficiently and gives the desired output in terms of energy consumption (MJ/ha). The advantage of this application is to decide the inputs on the basis of energy consumption before performing actual cultivation practice using the last season data. Moreover, using this package energy budget difference and comparison of subsequent production seasons can be achieved. The computer application was developed using Visual Basic, which allows the user to calculate total energy use efficiency, specific energy and different energy ratios in a particular cropping system.


2021 ◽  
Vol 267 ◽  
pp. 01006
Author(s):  
Guohua He ◽  
Xiaoling Li ◽  
Shan Jiang ◽  
Yongnan Zhu ◽  
Fan He ◽  
...  

This paper takes each province and region as the research object and 2017 as the research period, and the energy consumption of China’s social water cycle process was analyzed. The results showed that the total power consumption of China’s social water cycle process was 1082.81 billion kWh, accounting for 17.2% of the total power consumption of China’s society in 2017. Terminal water consumption is the biggest energy consumption. Based on the calculated results, this study puts forward relevant suggestions for realizing energy-water coordinated security.


Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4455 ◽  
Author(s):  
Vicente Mayor ◽  
Rafael Estepa ◽  
Antonio Estepa ◽  
Germán Madinabeitia

This paper formulates a new problem for the optimal placement of Unmanned Aerial Vehicles (UAVs) geared towards wireless coverage provision for Voice over WiFi (VoWiFi) service to a set of ground users confined in an open area. Our objective function is constrained by coverage and by VoIP speech quality and minimizes the ratio between the number of UAVs deployed and energy efficiency in UAVs, hence providing the layout that requires fewer UAVs per hour of service. Solutions provide the number and position of UAVs to be deployed, and are found using well-known heuristic search methods such as genetic algorithms (used for the initial deployment of UAVs), or particle swarm optimization (used for the periodical update of the positions). We examine two communication services: (a) one bidirectional VoWiFi channel per user; (b) single broadcast VoWiFi channel for announcements. For these services, we study the results obtained for an increasing number of users confined in a small area of 100 m2 as well as in a large area of 10,000 m2. Results show that the drone turnover rate is related to both users’ sparsity and the number of users served by each UAV. For the unicast service, the ratio of UAVs per hour of service tends to increase with user sparsity and the power of radio communication represents 14–16% of the total UAV energy consumption depending on ground user density. In large areas, solutions tend to locate UAVs at higher altitudes seeking increased coverage, which increases energy consumption due to hovering. However, in the VoWiFi broadcast communication service, the traffic is scarce, and solutions are mostly constrained only by coverage. This results in fewer UAVs deployed, less total power consumption (between 20% and 75%), and less sensitivity to the number of served users.


2020 ◽  
Vol 21 (5) ◽  
pp. 523
Author(s):  
Abidin Şahinoğlu ◽  
Efehan Ulas

In recent years, the necessity for energy in the manufacturing industry has become an important problem because fossil fuel reserves are decreasing in order to produce energy. Therefore, the efficient use of energy has become an important research topic. In this study, energy efficiency is investigated in detail for sustainable life and manufacturing. AISI 4140 material with high hardness of 50 HRC hardness has been applied cryogenic process to improve mechanical and machinability properties. In this experiment study, the effects of feed rate (0.04, 0.08, 0.12 mm/rev), cutting speed (140, 160, 180 m/min), depth of cut (0.05, 0.10, 0.15 mm) and tool radius (0.4, 0.8) on energy consumption, surface roughness and sound intensity were investigated. Then, a new mathematical model with high accuracy was developed. Total power consumption was calculated by considering the instantaneous current value and machining time. As a result, it is found that good surface quality obtained when the feed rate is low, and the tool radius is high and the machining time is shortened, the energy consumption is reduced due to the increase in cutting speed, depth of cut and feed rate. Also, it is found that the tool radius has a limited effect on energy consumption, but low feed value increases energy consumption.


2014 ◽  
Vol 27 (3) ◽  
pp. 435-453 ◽  
Author(s):  
Goran Nikolic ◽  
Mile Stojcev ◽  
Zoran Stamenkovic ◽  
Goran Panic ◽  
Branislav Petrovic

Wireless sensor network consists of a large number of simple sensor nodes that collect information from external environment with sensors, then process the information, and communicate with other neighboring nodes in the network. Usually, sensor nodes operate with exhaustible batteries unattended. Since manual replacement or recharging of the batteries is not an easy, desirable or always possible task, the power consumption becomes a very important issue in the development of these networks. The total power consumption of a node is a result of all steps of the operation: sensing, data processing and radio transmission. In most published papers in literature it is assumed that the sensing subsystem consumes significantly less energy than a radio block. However, this assumption does not apply in numerous applications, especially in the case when power consumption of the sensing activity is comparably bigger than that of a radio. In that context, in this work we focus on the impact of the sensing hardware on the total power consumption of a sensor node. Firstly, we describe the structure of the sensor node architecture, identify its key energy consumption sources, and introduce an energy model for the sensing subsystem as a building block of a node. Secondly, with the aim to reduce energy consumption we investigate joint effectiveness of two common power-saving techniques in a specific sensor node: duty-cycling and power-gating. Duty-cycling is effective at the system level. It is used for switching a node between active and sleep mode (with the duty-cycle factor of 1%, the reduction of in dynamic energy consumption is achieved). Power-gating is used at the circuit level with the goal to decrease the power loss due to the leakage current (in our design, the reduction of dynamic and static energy consumption of off-chip sensor elements as constituents of sensing hardware within a node of is achieved). Compared to a sensor node architecture in which both energy saving techniques are omitted, the conducted MATLsimulation results suggest that in total, thanks to involving duty-cycling and power-gating techniques, a three order of magnitude reduction for sensing activities in energy consumption can be achieved.


Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 134
Author(s):  
Łukasz Kułacz ◽  
Adrian Kliks ◽  
Paweł Kryszkiewicz ◽  
Bartosz Bossy

The development of wireless networks can be characterized by both the increased number of deployed network nodes as well as their greater heterogeneity. As a consequence, the distance between the neighboring nodes decreases significantly, the density of such a wireless network is very high, and it brings to the mind the analogy to the human brain and nervous system, where a highly simplified scheme of information delivery is applied. Motivated by this similarity, in this paper, we study the possibility of the application of various transmission profiles in order to optimize the overall energy consumption in such dense wireless networks. The transmission profile specifies the radio access and energy consumption of the wireless transceiver (network node), and is characterized by the tuple of parameters, e.g., the total transmit power or minimal required signal-to-noise ratio (SNR). In the considered multi-hop network, we assume that each node can be set to the most promising transmission profile to achieve some predefined goals, such as (sensor) network reliability or transmission energy efficiency. We have proposed the new graph-based routing algorithm in such a dense wireless network, where total power consumption of message delivery is minimized by multihop and multimode transmission. The theoretical definition of the prospective transmission schemes is supported by the analysis of the results of the simulation experiments.


Author(s):  
Элеонора Николаевна Трушина ◽  
Оксана Константиновна Мустафина ◽  
Татьяна Николаевна Солнцева ◽  
Валерий Дмитриевич Кузнецов

В исследовании участвовали 20 спортсменов-юниоров (мастера спорта и кандидаты в мастера спорта) в возрасте 17-18 лет и 10 добровольцев соответствующего возраста и интенсивности физической нагрузки. В результате исследований установлено, что суммарная калорийность потребленных за сутки продуктов в основном соответствовала энерготратам спортсменов обследованных групп. Соотношение белки/жиры/углеводы в суточном рационе спортсменов свидетельствует о недостаточной квоте углеводов в соответствии с формулой оптимального питания для юных спортсменов. При этом потребление добавленного сахара у спортсменов всех категорий превышало рекомендуемый уровень (10% от калорийности суточного рациона). The study involved 20 junior athletes (masters of sports and candidates for masters of sports) aged 17-18 and 10 volunteers of the corresponding age and intensity of physical activity. As a result of the research, it was found that the total calorie content of products consumed per day basically corresponded to the energy consumption of athletes in the surveyed groups. The ratio of protein / fat / carbohydrates in the daily diet of athletes indicates an insufficient carbohydrate quota in accordance with the optimal nutrition formula for young athletes. At the same time, the consumption of added sugar in athletes of all categories exceeded the recommended level (10% of the caloric content of the daily diet).


HortScience ◽  
1994 ◽  
Vol 29 (4) ◽  
pp. 249a-249
Author(s):  
Eric A. Lavoie ◽  
Damien de Halleux ◽  
André Gosselin ◽  
Jean-Claude Dufour

The main objective of this research was to produce a simulated model that permitted the evaluation of operating costs of commercial greenhouse tomato growers with respect to heating methods (hot air, hot water, radiant and heat pumps) and the use of artificial lighting for 1991 and 1992. This research showed that the main factors that negatively influence profitability were energy consumption during cold periods and the price of tomatoes during the summer season. The conventional hot water system consumed less energy than the heat pump system and produced marketable fruit yields similar to those from the heat pump system. The hot water system was generally more profitable in regards to energy consumption and productivity. Moreover, investment costs were less; therefore, this system gives best overall financial savings. As for radiant and hot air systems, their overall financial status falls between that of the hot water system and the heat pump. The radiant system proved to be more energy efficient that the hot air system, but the latter produced a higher marketable fruit yield over the 2-year study.


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