scholarly journals Evaluation of Autonomous Mowers Weed Control Effect in Globe Artichoke Field

2021 ◽  
Vol 11 (24) ◽  
pp. 11658
Author(s):  
Lorenzo Gagliardi ◽  
Mino Sportelli ◽  
Christian Frasconi ◽  
Michel Pirchio ◽  
Andrea Peruzzi ◽  
...  

The development of a fully automated robotic weeder is currently hindered by the lack of a reliable technique for weed-crop detection. Autonomous mower moving with random trajectories rely on simplified computational resources and have shown potential when applied for agricultural purposes. This study aimed to evaluate the applicability of these autonomous mowers for weed control in globe artichoke. A first trial consisting of the comparison of the performances of three different autonomous mowers (AM1, AM2 and AM3) was carried out evaluating percentage of area mowed and primary energy consumption. The most suitable autonomous mower was tested for its weed control effect and compared with a conventional weed management system. Average weeds height, weed cover percentage, above-ground weed biomass, artichoke yield, primary energy consumption and cost were assessed. All the autonomous mowers achieved a percentage of area mowed around the 80% after 180 min. AM2 was chosen as the best compromise for weed control in the artichoke field (83.83% of area mowed after 180 min of mowing, and a consumption of 430.50 kWh⋅ha−1⋅year−1). The autonomous mower weed management achieved a higher weed control effect (weed biomass of 71.76 vs. 143.67 g d.m.⋅m−2), a lower energy consumption (430.5 vs. 1135.13 kWh⋅ha−1⋅year−1), and a lower cost (EUR 2601.84 vs. EUR 3661.80 ha−1·year−1) compared to the conventional system.

2012 ◽  
Vol 9 (2) ◽  
pp. 65
Author(s):  
Alhassan Salami Tijani ◽  
Nazri Mohammed ◽  
Werner Witt

Industrial heat pumps are heat-recovery systems that allow the temperature ofwaste-heat stream to be increased to a higher, more efficient temperature. Consequently, heat pumps can improve energy efficiency in industrial processes as well as energy savings when conventional passive-heat recovery is not possible. In this paper, possible ways of saving energy in the chemical industry are considered, the objective is to reduce the primary energy (such as coal) consumption of power plant. Particularly the thermodynamic analyses ofintegrating backpressure turbine ofa power plant with distillation units have been considered. Some practical examples such as conventional distillation unit and heat pump are used as a means of reducing primary energy consumption with tangible indications of energy savings. The heat pump distillation is operated via electrical power from the power plant. The exergy efficiency ofthe primary fuel is calculated for different operating range ofthe heat pump distillation. This is then compared with a conventional distillation unit that depends on saturated steam from a power plant as the source of energy. The results obtained show that heat pump distillation is an economic way to save energy if the temperaturedifference between the overhead and the bottom is small. Based on the result, the energy saved by the application of a heat pump distillation is improved compared to conventional distillation unit.


Author(s):  
Katja Koehler-Cole ◽  
Christopher A. Proctor ◽  
Roger W. Elmore ◽  
David A. Wedin

Abstract Replacing tillage with cover crops (CC) for weed management in corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] systems with mechanical weed control has many soil health benefits but in the western Corn Belt, CC establishment after harvest is hampered by cold temperatures, limited labor and few compatible CC species. Spring-planted CC may be an alternative, but information is lacking on suitable CC species. Our objective was to evaluate four spring-planted CC with respect to biomass production and weed suppression, concurrent with CC growth and post-termination. Cover crop species tested were oat (Avena sativa L.), barley (Hordeum vulgare L.), brown mustard [Brassica juncea (L.) Czern.] and yellow mustard (Brassica hirta Moench). They were compared to no-CC treatments that were either tilled pre- and post-planting of soybean (no-CC tilled) or not tilled at all (no-CC weedy). CC were planted in late March to early April, terminated 52–59 days later using an undercutter, and soybean was planted within a week. The experiment had a randomized complete block design with four replications and was repeated for 3 years. Mustards and small grains produced similar amounts of biomass (1.54 Mg ha−1) but mustard biomass production was more consistent (0.85–2.72 Mg ha−1) than that of the small grains (0.35–3.81 Mg ha−1). Relative to the no-CC weedy treatment, mustards suppressed concurrent weed biomass in two out of 3 years, by 31–97%, and small grains suppressed concurrent weed biomass in only 1 year, by 98%. Six weeks after soybean planting, small grains suppressed weed biomass in one out of 3 years, by 79% relative to the no-CC weedy treatment, but mustards did not provide significant weed suppression. The no-CC tilled treatment suppressed weeds each year relative to the no-CC weedy treatment, on average 87%. The ineffective weed control by CC reduced soybean biomass by about 50% six weeks after planting. While spring-planted CC have the potential for pre-plant weed control, they do not provide adequate early season weed suppression for soybean.


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2538
Author(s):  
Praveen K. Cheekatamarla

Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a cogeneration approach loses its advantage as an energy efficient residential resource are identified as a function of electrical grid’s carbon footprint and primary energy efficiency. Compared to a heat pump heating system with a coefficient of performance (COP) of three, a 0.5 kW cogeneration system with 40% electrical efficiency is shown to lose its environmental benefit if the electrical grid’s carbon dioxide intensity falls below 0.4 kg CO2 per kWh electricity.


2018 ◽  
Vol 882 ◽  
pp. 215-220
Author(s):  
Matthias Koppmann ◽  
Raphael Lechner ◽  
Tom Goßner ◽  
Markus Brautsch

Process cooling and air conditioning are becoming increasingly important in the industry. Refrigeration is still mostly accomplished with compression chillers, although alternative technologies are available on the market that can be more efficient for specific applications. Within the scope of the project “EffiCool” a technology toolbox is currently being developed, which is intended to assist industrials users in selecting energy efficient and eco-friendly cooling solutions. In order to assess different refrigeration options a consistent methodology was developed. The refrigeration technologies are assessed regarding their efficiency, CO2-emissions and primary energy consumption. For CCHP systems an exergetic allocation method was implemented. Two scenarios with A) a compression chiller and B) an absorption chiller coupled to a natural gas CHP system were calculated exemplarily, showing a greater overall efficiency for the CCHP system, although the individual COP of the chiller is considerably lower.


Author(s):  
J Harrod ◽  
P J Mago

Due to the soaring costs and demand of energy in recent years, combined cooling, heating, and power (CCHP) systems have arisen as an alternative to conventional power generation based on their potential to provide reductions in cost, primary energy consumption, and emissions. However, the application of these systems is commonly limited to internal combustion engine prime movers that use natural gas as the primary fuel source. Investigation of more efficient prime movers and renewable fuel applications is an integral part of improving CCHP technology. Therefore, the objective of this study is to analyse the performance of a CCHP system driven by a biomass fired Stirling engine. The study is carried out by considering an hour-by-hour CCHP simulation for a small office building located in Atlanta, Georgia. The hourly thermal and electrical demands for the building were obtained using the EnergyPlus software. Results for burning waste wood chip biomass are compared to results obtained burning natural gas to illustrate the effects of fuel choice and prime mover power output on the overall CCHP system performance. Based on the specified utility rates and including excess production buyback, the results suggest that fuel prices of less than $23/MWh must be maintained for savings in cost compared to the conventional case. In addition, the performance of the CCHP system using the Stirling engine is compared with the conventional system performance. This comparison is based on operational cost and primary energy consumption. When electricity can be sold back to the grid, results indicate that a wood chip fired system yields a potential cost savings of up to 50 per cent and a 20 per cent increase in primary energy consumption as compared with the conventional system. On the other hand, a natural gas fired system is shown to be ineffective for cost and primary energy consumption savings with increases of up to 85 per cent and 24 per cent compared to the conventional case, respectively. The variations in the operational cost and primary energy consumption are also shown to be sensitive to the electricity excess production and buyback rate.


2005 ◽  
Vol 9 (3) ◽  
pp. 7-14 ◽  
Author(s):  
Hiromi Yamamoto ◽  
Kenji Yamaji

The uses of fossil fuels cause not only the resources exhaustion but also the environmental problems such as global warming. The purposes of this study are to evaluate paths to ward sustainable energy systems and roles of each renewable. In order to realize the purposes, the authors developed the global land use and energy model that figured the global energy supply systems in the future considering the cost minimization. Using the model the authors conducted a simulation in C30R scenario, which is a kind of strict CO2 emission limit scenarios and reduced CO2 emissions by 30% compared with Kyoto protocol forever scenario, and obtained the following results. In C30R scenario bio energy will supply 33% of all the primary energy consumption. How ever, wind and photo voltaic will supply 1.8% and 1.4% of all the primary energy consumption, respectively, because of the limits of power grid stability. The results imply that the strict limits of CO2 emissions are not sufficient to achieve the complete renewable energy systems. In order to use wind and photo voltaic as major energy resources we need not only to reduce the plant costs but also to develop unconventional renewable technologies. .


2014 ◽  
Vol 962-965 ◽  
pp. 1779-1781
Author(s):  
Ying Chun Yang

Rapid economic growth in China induces higher energy consumption. This article establishes a primary energy consumption model. Finally, this article puts forward energy policies for ensuring economic growth and simultaneously achieving emission reduction and energy conversation.


2014 ◽  
Vol 30 (4) ◽  
pp. 37-50 ◽  
Author(s):  
Jacek Kamiński

Streszczenie W artykule przedstawiono model matematyczny, który możne być zastosowany do badań i analiz dotyczących zużycia energii pierwotnej w sektorze energetycznym dla różnych struktur rynkowych. Choć problematyka ta była już przedmiotem badań w kontekście regulacji środowiskowych czy postępu technologicznego, według najlepszej wiedzy autora wcześniejsze prace nie omawiały problematyki zużycia paliw pierwotnych w zależności od struktur rynkowych. W artykule sfor- mułowano model matematyczny, który umożliwia takie analizy. Model jest oparty na koncepcji teorii gier - zastosowano podejście Coumota z uwzględnieniem oczekiwanych zmian (Conjectural Yariations - CV). Model został sformułowany jako problem programowania mieszanego komple- mentarnego (Mbced Complementarity Problem - MCP), który szczególnie nadaje się do modelowania systemów paliwowo-energetycznych w kontekście rynkowym. Przyjęto założenie o uwzględnieniu dwóch hurtowych rynków obrotu energią elektryczną, a mianowicie rynku dnia następnego (RDN) oraz rynku bilateralnego (OTC). Model może być zaimplementowany w dowolnym systemie mode- lowania wykorzystywanym do budowy matematycznych modeli systemów paliwowo-energetycz- nych. Oprócz analiz zużycia energii pierwotnej w sektorze energetycznym model będzie mógł być również wykorzystany do analiz ekonomicznych, w szczególności analiz dobrobytu konsumentów i producentów, strat społecznych oraz cen i wielkości produkcji. Badania przedstawione w niniejszym artykule będą kontynuowane, w szczególności w zakresie pozyskania danych i kalibracji modelu. `


2016 ◽  
Vol 32 (3) ◽  
pp. 5-22 ◽  
Author(s):  
Katarzyna Stala-Szlugaj

Abstract Due to the important role of hard coal in the Polish residential sector, the article traced the changes that have occurred in the use of this fuel in the European Union and in Poland in the years 1990–2014. Throughout the European Union, hard coal has an important place in the structure of primary energy consumption. In the years 1990–2014, primary energy consumption in the European Union (calculated for all 28 Member States) has changed between 1507 and 1722 million toe. Between 2014 and 1990, there was a decrease of primary energy consumption, and the average rate of decline amounted to −0.2%. According to Council Directive 2013/12/EU, by the year 2020 energy consumption throughout the EU is expected to be no more than 1483 Mtoe of primary energy, and already in 2014 total primary energy consumption in the EU28 was higher than assumed by this target by only about 24 million toe (2%). Actions taken to protect the climate result in reducing the consumption of hard coal in the European Union. Between 1990 and 2014, the consumption of hard coal decreased by 41% (a decrease of 126 million toe), and the average rate of decline in consumption of this fuel amounted to −2.1%. Throughout the EU, households are not as significant a consumer of hard coal, as in Poland. Although EU28’s coal consumption in this sector in the years 1990 to 2014 varied between 6.5–15.8 million toe, its share in the overall consumption of this fuel usually maintained at around 3–5%. The changing fuel mix, closing of mines or gradual extinction of coal mining, environmental policy of the individual countries meant that coal has lost its position in some of them. Analyzing the structure of hard coal consumption by households in the EU28 countries in the years 1900 to 2014, one may notice that the leaders are those countries that have their own coal mines. Due to the structure of consumption of hard coal by the customers, the article discussed two countries: Poland and Great Britain in greater detail. In 1990, Poland (50%) and Britain (18%) were close leaders, and twenty-five years later, only Poland has remained in first place (84%) and Great Britain has fallen to fourth place (4%). Between 2014 and 1990, the consumption of hard coal by the British residential sector decreased by 88% to only 0.3 million toe. In the case of Poland, it admittedly decreased by 6%, but still exceeds 6 million toe. The decrease in hard coal consumption in Great Britain was largely a consequence of The Clean Air Act introduced in 1956. In Britain, the process of replacing coal with other fuels (mostly natural gas) lasted several decades. Domestic coal was replaced with another mainly domestic resource – natural gas which ensured the security of its supply. The article also describes the households in the European Union and in Poland. The overall housing stock was taken into account, together with the distribution of population according to the degree of urbanization. Regulations that have a significant impact on the consumption of energy in the European Union were also discussed.


2021 ◽  
Vol 144 ◽  
pp. 14-21
Author(s):  
Vladimir P. Polevanov ◽  

The growth in primary energy consumption in 2019 by 1.3% was provided by renewable energy sources and natural gas, which together provided 75% of the increase. China in the period 2010–2020 held a leading position in the growth of demand for energy resources, but according to forecasts, India will join it in the current decade.


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