New Compressor Concepts: Reduction of Energy Consumption and Improved Quality of Compressed Air

Abstract This review covers the effect of mechanical pre-treatment of wood chips on the energy consumption in refining and the quality of pulp. To understand the mechanisms of mechanical pre-treatment, a short description of relevant refining theory and reported effects of pre-treatment on wood morphology is given. Mechanical pre-treatment offers a chance to utilize the energy needed to defibrate chips in a more efficient way, minimizing the cyclic elastic deformations which are the main defibration mechanism in refining. Studies of fibre morphology indicate that compressive pretreatment mechanically introduces favorable weak points in the S1 and S2 fibre walls where defibration proceeds easier upon subsequent refining. Published results which cover the effect of the pretreatment on energy consumption and pulp properties are reviewed. Energy reduction of between 10% and 30% is reported in the literature. High ratio of volumetric compression is necessary. Pressurized conditions are required to ensure that the fibres are not damaged during the pre-treatment. Other effects of compressive pretreatment include a more uniform chip size and moisture content, better penetration of chemicals and removal of extractives from the chips. A list of equipment used for chip pre-compression is provided together with published results of pilot-scale and mill-scale operation.

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Design of a Traffic-Aware Governor for Green Routers

Journal of Electrical and Computer Engineering ◽

10.1155/2014/683408 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12

Author(s):

Alfio Lombardo ◽

Vincenzo Riccobene ◽

Giovanni Schembra

Keyword(s):

Quality Of Service ◽

Energy Consumption ◽

Energy Saving ◽

Analytical Model ◽

Case Scenario ◽

Proposed Model ◽

Traffic Impacts ◽

Reduction Of Energy Consumption

Today the reduction of energy consumption in telecommunications networks is one of the main goals to be pursued by manufacturers and researchers. In this context, the paper focuses on routers that achieve energy saving by applying the frequency scaling approach. The target is to propose an analytical model to support designers in choosing the main configuration parameters of the Router Governor in order to meet Quality of Service (QoS) requirements while maximizing energy saving gain. More specifically, the model is used to evaluate the input traffic impacts on the choice of the active router clock frequencies and on the overall green router performance. A case study based on the open NetFPGA reference router is considered to show how the proposed model can be easily applied to a real case scenario.

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Harmonics and Reduction of Energy Consumption in Lighting Systems by Using LED Lamps

Energies ◽

10.3390/en11113169 ◽

2018 ◽

Vol 11 (11) ◽

pp. 3169 ◽

Cited By ~ 8

Author(s):

Natthanon Phannil ◽

Chaiyan Jettanasen ◽

Atthapol Ngaopitakkul

Keyword(s):

Energy Consumption ◽

Power Quality ◽

Power Factor ◽

Energy Savings ◽

Light Emitting Diode ◽

Total Power ◽

Increase Energy Efficiency ◽

Lighting Systems ◽

Reduction Of Energy Consumption

This paper proposes the study and analysis of harmonics, energy consumption and power quality of light emitting diode (LED) lamps equipped in building lighting systems. LED lamps with external (LED MR16) and internal (LED light bulb) drivers are investigated using an experimental setup to compare the results. The power quality of both LED lamps is studied by using a power quality meter to measure the generated harmonic currents from various case studies. The case study is divided into four major cases: one LED lamp is turned on with one driver, two LED lamps are turned on using the two drivers, eight LED lamps are turned on with one driver, and eight LED lamps are turned on with the eight drivers. As harmonics are related to total power factor (PF), which affects the energy savings of the building, hence, a filtering circuit to reduce harmonic current has been designed and implemented to improve power quality and/or power factor of the system. The different cases of harmonic filter insertion at the input of an LED lamp’s driver are discussed and then compared with a lighting standard to show the effectiveness of the passive filtering technique used in the studied system. In addition, the obtained result can be applied to both newly built and retrofitted buildings that aim to use LED technology to increase energy efficiency and decrease energy costs, and could be a helpful guide for end-users and manufacturers in addressing and developing LED issues.

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Development of an optimized game controller for energy saving in a novel interconnected air suspension system

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407020927147 ◽

2020 ◽

Vol 234 (13) ◽

pp. 3068-3080 ◽

Cited By ~ 1

Author(s):

Hossein Nazemian ◽

Masoud Masih-Tehrani

Keyword(s):

Energy Consumption ◽

Body Position ◽

The Body ◽

Air Pressure ◽

Roll Angle ◽

Compressed Air ◽

Air Suspension ◽

Game Controller ◽

Minor Road ◽

Reduction Of Energy Consumption

In this study, the focus is on reducing the energy that is consumed by a compressor for providing high air pressure in the reservoir. A new air suspension configuration is presented that is titled active interconnected air suspension with outsourced air pressure. In this configuration, a compressor is used to charge the tank; meanwhile, the air springs are connected. For minor excitation, first, the air flows between air springs to control roll angle and height adjustment. If the situation of body position gets worse, the compressed air tank compensates to keep the body not generating roll angle and bounce. This methodology has a benefit. This configuration conserves compressed air in the tank in minor road elevation. The optimized controllers are designed to control roll angle and bounce, but they determine the outsourced air mass flow rate. For switching between interconnection and outsourced mode, there are some rules defined based on game theory for a trade-off between high dynamical performance quality of the vehicle and reduction of energy consumption. The optimization is done on the rules to keep both aspects minimum as much as possible. A three-axle heavy truck is used, and its performance is under discussion on an uneven rough road. Roll angle is improved progressively in novel air suspension configuration, and the energy consumption is reduced. In the default condition, the roll angle is improved 72% from the passive case and 39% from the conventional configuration. Furthermore, the energy consumption optimized version reduces 14% from the non-optimized case and 46% from the outsourced mode. By importing road power spectral density type E and type G, as the short domain and high-frequency vibrations, to two sides of the truck, it is inferred that the vehicle could remain on interconnection mode entirely without using the compressor.

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Analysis of Energy Consumption and Optimization Techniques for Writing Energy-Efficient Code

Electronics ◽

10.3390/electronics8101192 ◽

2019 ◽

Vol 8 (10) ◽

pp. 1192 ◽

Cited By ~ 1

Author(s):

Javier Corral-García ◽

Felipe Lemus-Prieto ◽

José-Luis González-Sánchez and Miguel-Ángel Pérez-Toledano

Keyword(s):

Energy Consumption ◽

Energy Efficient ◽

Optimization Techniques ◽

Raspberry Pi ◽

Software Systems ◽

Major Subject ◽

Efficient Code ◽

Reduction Of Energy Consumption ◽

The Internet Of Things

The unprecedented growth of connected devices, together with the remarkable convergence of a wide variety of technologies, have led to an exponential increase in the services that the internet of things (IoT) can offer, all aimed at improving quality of life. Consequently, in order to meet the numerous challenges this produces, the IoT has become a major subject of research. One of these challenges is the reduction of energy consumption given the significant limitations of some devices. In addition, although the search for energy efficiency was initially focused on hardware, it has become a concern for software developers too. In fact, it has become an intense area of research with the principal objective of analyzing and optimizing the energy consumption of software systems. This research analyzes the energy saving that can be achieved when using a broad set of techniques for writing energy-efficient code for Raspberry Pi devices. It also demonstrates that programmers can save more energy if they apply the proposed techniques manually than when relying on other automatic optimization options offered by the GNU compiler collection (GCC). Thus, it is important that programmers are aware of the significant impact these techniques can have on an application’s energy consumption.

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China: "A Bee Has a Stripy Back, but No One Can Call It a Tiger"

Voprosy Ekonomiki ◽

10.32609/0042-8736-2003-3-61-75 ◽

2003 ◽

pp. 61-75

Author(s):

V. Guelbras

Keyword(s):

Energy Consumption ◽

Gdp Growth ◽

International Demand ◽

Real Size ◽

Rates Of Growth

The article is devoted to verification of the Chinese GDP data. The author compares the rates of GDP growth with the rates of growth of energy consumption, transport turnover of goods, and numbers of projected and constructed objects in 1980-2000. The former was significantly lower during that period. He also analyses the level of using productive capacities and the quality of production. About 25-30% of industrial productive capacities are not used because there is neither national nor international demand for their low quality goods. The main conclusion of the article is that the Chinese GDP real size is about 20-30% less than official releases.

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