scholarly journals Energy consumption for different greenhouses' structures

2008 ◽  
Vol 53 (1) ◽  
pp. 71-78
Author(s):  
Milan Djevic ◽  
Aleksandra Dimitrijevic

In this paper influence of greenhouses' structure was estimated for four different double plastic covered greenhouses in winter lettuce production. Plastic coverings are introduced as mean of making this kind of plant production more efficient. Also, as a mean of lowering energy consumption, the tunnel structures are proposed. Four different double plastic covered greenhouses were used for energy analysis. Two tunnel types, 9 x 58m and 8 x 25m covered with double PE folia, and two gutter connected plastic covered greenhouses. One greenhouse is 2 x 7 m wide and 39 m long and the other 20 x 6.4 m wide and 42 m long. Results have shown the lowest energy consumption for gutter connected greenhouses. Energy out/in ratio was also higher in gutter connected greenhouse. Highest energy consumption was obtained in tunnel greenhouse 8 x 25m.


2021 ◽  
Vol 11 (6) ◽  
pp. 2735
Author(s):  
Ernesto Olvera-Gonzalez ◽  
Martín Montes Rivera ◽  
Nivia Escalante-Garcia ◽  
Eduardo Flores-Gallegos

Artificial lighting is a key factor in Closed Production Plant Systems (CPPS). A significant light-emitting diode (LED) technology attribute is the emission of different wavelengths, called light recipes. Light recipes are typically configured in continuous mode, but can also be configured in pulsed mode to save energy. We propose two nonlinear models, i.e., genetic programing (GP) and feedforward artificial neural networks (FNNs) to predict energy consumption in CPPS. The generated models use the following input variables: intensity, red light component, blue light component, green light component, and white light component; and the following operation modes: continuous and pulsed light including pulsed frequency, and duty cycle as well energy consumption as output. A Spearman's correlation was applied to generate a model with only representative inputs. Two datasets were applied. The first (Test 1), with 5700 samples with similar input ranges, was used to train and evaluate, while the second (Test 2), included 160 total datapoints in different input ranges. The metrics that allowed a quantitative evaluation of the model's performance were MAPE, MSE, MAE, and SEE. Our implemented models achieved an accuracy of 96.1% for the GP model and 98.99% for the FNNs model. The models used in this proposal can be applied or programmed as part of the monitoring system for CPPS which prioritize energy efficiency. The nonlinear models provide a further analysis for energy savings due to the light recipe and operation light mode, i.e., pulsed and continuous on artificial LED lighting systems.



2021 ◽  
Vol 11 (6) ◽  
pp. 2772
Author(s):  
Bin Li ◽  
Zhiheng Zeng ◽  
Xuefeng Zhang ◽  
Ye Zhang

To realize energy-saving and efficient industrial grain drying, the present work studied the variable-temperature drying process of corn drying in a novel industrial corn-drying system with a heat recycling and self-adaptive control function. The drying kinetics, thermal performance, heat-loss characteristics and the heat-recycling performance of the drying system under different allocations between flue gas and hot air were investigated, and the optimized drying process was proposed and compared with two constant drying processes. The results showed that the optimized drying process exhibited better drying kinetic and thermal performance than the two constant drying processes. More specifically, the total heat loss, total energy consumption and specific energy consumption of the optimized drying process were ascertained to be 36,132.85 MJ, 48,803.99 MJ and 7290.27 kJ/kg, respectively, which were lower than those of the other two processes. On the other hand, the thermal efficiency of the drying chamber for the optimized drying process was ascertained to be varied within the range of 6.81–41.71%. Overall, the validation results showed that the optimized drying process can significantly improve the drying performance of the drying system.



2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Hossein Ahmadvand ◽  
Fouzhan Foroutan ◽  
Mahmood Fathy

AbstractData variety is one of the most important features of Big Data. Data variety is the result of aggregating data from multiple sources and uneven distribution of data. This feature of Big Data causes high variation in the consumption of processing resources such as CPU consumption. This issue has been overlooked in previous works. To overcome the mentioned problem, in the present work, we used Dynamic Voltage and Frequency Scaling (DVFS) to reduce the energy consumption of computation. To this goal, we consider two types of deadlines as our constraint. Before applying the DVFS technique to computer nodes, we estimate the processing time and the frequency needed to meet the deadline. In the evaluation phase, we have used a set of data sets and applications. The experimental results show that our proposed approach surpasses the other scenarios in processing real datasets. Based on the experimental results in this paper, DV-DVFS can achieve up to 15% improvement in energy consumption.



Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1603
Author(s):  
Ernesto Olvera-Gonzalez ◽  
Nivia Escalante-Garcia ◽  
Deland Myers ◽  
Peter Ampim ◽  
Eric Obeng ◽  
...  

Different strategies are reported in the literature for energy saving in Closed Plant Production Systems (CPPS). However, not reliable evidences about energy consumption with the use of pulsed LED light technique in lighting system available in Plant Factory and Vertical Farm. In this work, three key points to determine the effects of pulsed LED light versus continuous LED light are presented: (1) A mathematical model and its practical application for stabilizing the energy equivalence using LED light in continuous and pulsed mode in different light treatments. (2) The quantum efficiency of the photosystem II was used to determine positive and/or negative effects of the light operating mode (continuous or pulsed) on chili pepper plants (Capsicum annuum var. Serrano). (3) Evaluation of energy consumption with both operation modes using ten recipes from the literature to grow plants applied in Closed Plant Production Systems, different Photosynthetic Photon Flux Density at 50, 110, and 180 µmol m−2 s−1, Frequencies at 100, 500, and 1000 Hz, and Duty Cycles of 40, 50, 60, 70, 80, and 90%. The results show no significant statistical differences between the operation modes (continuous and pulsed LED light). For each light recipe analyzed, a pulsed frequency and a duty cycle were obtained, achieving significant energy savings in every light intensity. The results can be useful guide for real-life applications in CPPS.



Author(s):  
N.B. Afonina ◽  
A.V. Otrokov ◽  
G.Sh. Khazanovich

Most modern roadheaders of selective action are equipped with loading devices with gathering-stars, which have a simpler drive design and increased reliability. As a result of the experimental studies carried out at SRSPU (NPI), it was found that under certain conditions, it is possible to transfer large lump material of a pile into a fluidized state, which reduces the energy consumption of material loading. An increase in the number of beams of the gathering-stars reduces the influence of the other parameters of the loader. Analysis of the process of interaction of the gathering-star’s beam with the receiving conveyor’s side edge to avoid jamming of the picking gathering-star by a lump of material with the implementation of high dynamic loads, it is necessary to set the gathering-beams at an angle of at least 60 degrees against rotation.



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 ◽  
Author(s):  
Abdulqader Mahmoud ◽  
Frederic Vanderveken ◽  
Florin Ciubotaru ◽  
Christoph Adelmann ◽  
Said Hamdioui ◽  
...  

In this paper, we propose an energy efficient SW based approximate 4:2 compressor comprising a 3-input and a 5-input Majority gate. We validate our proposal by means of micromagnetic simulations, and assess and compare its performance with one of the state-of-the-art SW, 45nm CMOS, and Spin-CMOS counterparts. The evaluation results indicate that the proposed compressor consumes 31.5\% less energy in comparison with its accurate SW design version. Furthermore, it has the same energy consumption and error rate as the approximate compressor with Directional Coupler (DC), but it exhibits 3x lower delay. In addition, it consumes 14% less energy, while having 17% lower average error rate than the approximate 45nm CMOS counterpart. When compared with the other emerging technologies, the proposed compressor outperforms approximate Spin-CMOS based compressor by 3 orders of magnitude in term of energy consumption while providing the same error rate. Finally, the proposed compressor requires the smallest chip real-estate measured in terms of devices.



2017 ◽  
Vol 86 (2) ◽  
Author(s):  
Waldemar Kiszczak ◽  
Urszula Kowalska ◽  
Agata Kapuścińska ◽  
Maria Burian ◽  
Krystyna Górecka

Doubled haploid lines of carrot can be obtained through androgenesis in anther cultures and in isolated microspore cultures. The two methods were compared using three carrot cultivars (‘Kazan F1’, ‘Feria F1’, and ‘Narbonne F1’) at the androgenesis induction stage, during plant regeneration from embryos, and during acclimatization of androgenetic plants as well as their characterization. It was found that cultivar was the main factor affecting the efficiency at each stage of plant production in both anther and isolated microspore cultures. The efficiency of androgenesis in anther cultures of ‘Feria F1’ was considerably higher in comparison with isolated microspore cultures, and more plants were obtained from the embryos of androgenesis-cultured plants. In ‘Kazan F1’ and ‘Narbonne F1’, more acclimatized androgenetic plants were produced from anther cultures. Ploidy assessment of acclimatized plants of ‘Narbonne F1’ showed that the majority of the plants in the population derived from anther cultures had a doubled chromosome (DH) set. On the other hand, the majority of plants obtained from isolated microspore cultures were haploids. When assessing homozygosity, it was found among plants obtained in anther cultures that the percentage of homozygotes for phosphoglucose isomerase (PGI) and aspartate aminotransferase (AAT) depended on the cultivar. In contrast, the majority of plants derived from isolated microspore cultures were homozygous regardless of cultivar.



2018 ◽  
Vol 8 (6) ◽  
pp. 3570-3575
Author(s):  
E. V. Palconit ◽  
M. L. S. Abundo

An electric boat system as a pilot study for the electric ferry was designed and field-tested in Samal Island, Philippines, to verify sustainability for inter-island transport. This pilot study uses 4.5m monohull with a displacement weight of 343kg. During the experiment, two cases were compared: in the first case the boat was powered solely with batteries and in the other case with the aid of photovoltaic (PV) modules. For the first case, 24V electric propulsion was driven by two 12V, 100Ah batteries, which resulted to a navigational range of around 18, 16 and 15 trips with energy consumption of 111.64Wh, 117.19Wh and 123.92Wh respectively. In the second case, the photovoltaic modules were attached on the boat to supplement the PV used while on sail. Results in the second case showed that PV module supplemented energy was about to 13.4%, 26.8% and 38.7% using three different speeds like 3.18, 3.32 and 3.84knots and the navigational range extended to 4km, 1km, and 14.4km respectively. Therefore, the electric boat with the aid of PV module answers the problem in the energy management system that deals with the sustainability of the system in the inter-island transport in Philippines.



Author(s):  
Vasily G. Moshnyaga

With the explosive use of personal computers or PCs, reducing computer energy consumption is paramount for sustainability. The display is the largest energy consumer in a personal computer. Current display energy management technologies ignore the attention of the PC user and therefore may either switch the display off when the user looks at the screen or lose energy by keeping the display on when nobody looks at it. This chapter discusses a new display energy management technology and outlines its implementation in a personal computer system. Unlike existing technologies, which “sense” a PC user through keyboard and/or mouse or the other sensors, this technology “watches” the user through a single camera or CMOS vision sensor. The technology tracks the user’s eyes, keeping display active only if the user looks at its screen. Otherwise, it dims the display down or even switches it off to save energy. The authors implemented the technology in software and hardware and present the results of their experimental evaluation.



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