End-use energy analysis in the Malaysian industrial sector

The industrial sector is the second largest consumer of energy in Malaysia. In this energy audit, the most important parameters that have been collected are as follows: power rating and operation time of energy-consuming equipments/machineries; fossil fuel and other sources of energy use; production figure; peak and off-peak tariff usage behavior and power factor. These data were then analyzed to investigate the breakdown of end-use equipments/machineries energy use, the peak and off-peak usage behavior, power factor trend and specific energy use. The results of the energy audit showed that the highest electrical energy-using equipment was an electric motor followed by pumps and air compressors. The specific energy use has been estimated and compared with four Indonesian industries and it was found that three Malaysian industries were more efficient than the Indonesian counterpart. The study also found that about 64% electrical energy was used in peak hours by the industries and the average power factor ranged from 0.88 to 0.92. The study also estimated energy and bill savings using highly efficient electrical motors along with the payback period.     

Energy and emission analysis for industrial motors in Malaysia

The industrial sector is the largest user of energy in Malaysia. Industrial motors account for a major segment of total industrial energy use. Since motors are the principle energy users, different energy savings strategies have been applied to reduce their energy consumption and associated emissions released into the atmosphere. These strategies include using highly efficient motors, variable speed drive (VSD), and capacitor banks to improve the power factor. It has been estimated that there can be a total energy savings of 1765, 2703 and 3605 MWh by utilizing energy-efficient motors for 50%, 75% and 100% loads, respectively. It was also found that for different motor loads, an estimated US$115,936 US$173,019 and US$230,693 can be saved in anticipated energy costs. Similarly, it is hypothesized that a significant amount of energy can be saved using VSD and capacitor banks to reduce speed and improve the power factor, thus cutting energy costs. Moreover, a substantial reduction in the amount of emissions can be effected together with the associated energy savings for different energy savings strategies. In addition, the payback period for different energy savings strategies has been found to be reasonable in some cases.     

Energy,economic and environmental benefits of using high-efficiency motors to replace standard motors for the Malaysian industries

Electric motors use major share (i.e. about 30–80% of total industrial energy consumption) of total industrial energy use around the world. Experiences from other countries show that government intervention in the form of regulations such as mandatory and voluntary approaches can save sizeable amount of energy along with the reduction in emissions associated with energy savings. This paper presents potential energy savings by introducing high-efficiency motors as a case study in Malaysian industrial sector. Emission reductions associated with the energy savings has been estimated and presented as well. It was also estimated that a cumulative amount of 1940 and 892 GWh of energy can be saved for 20 and 120 kW motors, respectively, in Malaysia relative to BAU over the next 10 years. Similarly, a cumulative amount of USD 100 million and USD 60 million can be saved as utility bills for the same motor categories. It has been found that the payback period of different capacities of motors are less than a year. Based on results, it was found that 1789 million kg of CO₂ emission can be avoided by replacing standard motors with high-efficiency motors.     

An end-use energy analysis in a Malaysian public hospital

The commercial sector consumes 8–50% of the total energy consumption for a few selected countries around the world. An energy audit was conducted in a Malaysian public hospital to identify energy using equipment and their energy consumption breakdown. Different energy saving measures have been identified and applied for electrical motors used in this hospital. It was estimated that this hospital consumed about 19,311 MW h for the year 2008. It was also estimated that about 212 MW h, 250 MW h and 317 MW h of annual energy can be saved using energy-efficient motors at 50%, 75% and 100% loads, respectively. In addition, use of variable speed drives are expected to save 1735 MW h, 4048 MW h and 6361 MW h of annual energy consumption for 20%, 40% and 60% speed reductions, respectively. It was found that the payback period for using high efficiency motors at different loads is less than a year which is economically very viable. However, the use of variable speed drives was found to be economically viable for larger motors for higher speed reductions. The study also found that a sizeable amount of emissions can be reduced for the different energy savings measures applied for electrical motors.     

Energy efficiency in pumps

In this paper, “energy efficiency” studies, done in a big industrial facility’s pumps, are reported. For this purpose; the flow rate, pressure and temperature have been measured for each pump in different operating conditions and at maximum load. In addition, the electrical power drawn by the electric motor has been measured. The efficiencies of the existing pumps and electric motor have been calculated by using the measured data.

Potential energy saving opportunities have been studied by taking into account the results of the calculations for each pump and electric motor. As a conclusion, improvements should be made each system. The required investment costs for these improvements have been determined, and simple payback periods have been calculated.

The main energy saving opportunities result from: replacements of the existing low efficiency pumps, maintenance of the pumps whose efficiencies start to decline at certain range, replacements of high power electric motors with electric motors that have suitable power, usage of high efficiency electric motors and elimination of cavitation problems.     

Line start permanent magnet synchronous motors: Challenges and opportunities

Future energy challenges, likewise the environmental crises such as fossil fuel emissions and global warming urge the world to focus on energy saving programs more than ever. An effective way to face these challenges is to improve electric motors efficiency as one of the greatest energy consumption apparatuses in the world. Induction motors constitute, by far, the largest portion of electric motors both in terms of quantity and total power ratings among all electric motors. However, more efficient motor types gradually appear as alternatives. In this paper, line start permanent magnet motors as a powerful candidate with growing market are investigated in some details. The motor opportunities like high efficiency, high power factor and high power density are explored against the challenges associated with this motor including higher cost, extra manufacturing burden and transient and synchronization behaviors. Finally, some concluding comments and remarks are drawn for future research and manufacturing of line start permanent magnet motors.     

A review on electrical motors energy use and energy savings

The industrial sector is the largest users of energy around the world. Industrial motor uses a major fraction of total industrial energy uses. This paper describes a comprehensive literature review about electric motor energy analysis. This paper compiles latest literatures in terms of thesis (MS and PhD), journal articles, conference proceedings, web materials, reports, books, handbooks on electrical motor energy use, losses, efficiency, energy savings strategies. Different types of losses that occur in a motor have been identified and ways to overcome these losses explained. An energy audit that helps to identify motor energy wastages have been discussed extensively. As motors are the major energy users, different energy savings strategies such as use of high-efficient motor, variable speed drive (VSD), and capacitor bank to improve the power factor to reduce their energy uses have reviewed. Different policy measures (i.e. regulatory, voluntary and incentives based) to save motor energy use have been reviewed and presented in this paper. In this review, computer tools that can be used to analyze electric motors energy used has been discussed. Cost parameters to carry out economic analysis have been shown as well. Moreover, payback period for different energy savings strategies have been identified.     

A model for improving energy efficiency in industrial motor system using multicriteria analysis

In the last years, several policies have been proposed by governments and global institutions in order to improve the efficient use of energy in industries worldwide. However, projects in industrial motor systems require new approach, mainly in decision making area, considering the organizational barriers for energy efficiency. Despite the wide application, multicriteria methods remain unexplored in industrial motor systems until now. This paper proposes a multicriteria model using the PROMETHEE II method, with the aim of ranking alternatives for induction motors replacement. A comparative analysis of the model, applied to a Brazilian industry, has shown that multicriteria analysis presents better performance on energy saving as well as return on investments than single criterion. The paper strongly recommends the dissemination of multicriteria decision aiding as a policy to support the decision makers in industries and to improve energy efficiency in electric motor systems.     

A review on compressed-air energy use and energy savings

Compressed-air systems account for about 10% of total industrial-energy use for few selected countries as found in literatures. Compressed air is typically one of the most expensive utilities in an industrial facility. This paper describes a comprehensive literature review about compressed air energy use, savings, and payback period of energy efficient strategies. This paper compiles latest literatures in terms of thesis (MS and PhD), journal articles, conference proceedings, web materials, reports, books, handbooks on compressed air energy use, efficiency, energy savings strategies. Computer tools for compressed air analysis have been reviewed and presented in this paper. Various energy-saving measures, such as use of highly efficient motors, VSD, leak prevention, use of outside intake air, reducing pressure drop, recovering waste heat, use of efficient nozzle, and use of variable displacement compressor to save compressed-air energy have been reviewed. Based on review results, it has been found that for an electric motor used in a compressed-air system, a sizeable amount of electric energy and utility bill can be saved using high efficient motors and applying VSDs in matching speed requirements. Also, significant amounts of energy and emission are reducible through various energy-saving strategies. Payback periods for different energy savings measures have been identified and found to be economically viable in most cases.     

Method for in-field evaluation of the stator winding connection of three-phase induction motors to maximize efficiency and power factor

The performance of the oversized three-phase induction motors can be improved, both in terms of efficiency and power factor, with the proper change of the stator winding connection, which can be delta or star, as a function of their load. A practical method is proposed to quickly and easily evaluate which stator winding connection is more appropriate for the actual motor load profile, in order to increase the motor efficiency and power factor. This new method is suitable for in-field evaluation, because it requires only the use of inexpensive equipment and has enough accuracy to allow a proper decision to be made. The automatic change of the stator winding connection, as a function of the motor line current, is also analyzed. When properly applied, these methods can lead to the improvement of the efficiency and power factor of permanently oversized motors, motors with a load variation between low load and near full load during their duty cycle, and/or motors driving high-inertia, low duty cycle loads. The proposed methods are particularly suitable to industrial plants where typically many electric motor systems are oversized and/or can have a wide load variation. In these conditions, the active and reactive electrical energy bill can be significantly reduced.     

Energy management of a fuel cell hybrid ultra-energy efficient vehicle

This paper focuses on energy management in an ultra-energy efficient vehicle powered by a hydrogen fuel cell with rated power of 1 kW. The vehicle is especially developed for the student competition Shell Eco-marathon in the Urban Concept category. In order to minimize the driving energy consumption a simulation model of the vehicle and the electric propulsion is developed. The model is based on vehicle dynamics and real motor efficiency as constant DC/DC, motor controllers and transmission efficiency were considered. Based on that model five propulsion schemes and driving strategies were evaluated. The fuel cell output parameters were experimentally determined. Then, the driving energy demand and hydrogen consumption was estimated for each of the propulsion schemes. Finally, an experimental study on fuel cell output power and hydrogen consumption was conducted for two propulsion schemes in case of hybrid and non-hybrid power source. In the hybrid propulsion scheme, supercapacitors were used as energy storage as they were charged from the fuel cell with constant current of 10 A.     

Energy conservation by using energy efficient electric motors

This paper deals with energy conservation by installing energy-efficient (EE) motors instead of standard efficiency motors. This transition become a necessity as a direct result of limitation in energy sources and escalating energy prices. As electric motors use about three quarters of the total electric energy in Bahrain, attempts to conserve the energy consumed by electric motors recently received intensive research efforts. Therefore, the energy efficiencies of energy efficient motors are compared with those of standard efficiency motors ranging from 5 to 300 HP. To provide more clarification in this regard, full design details of 200 HP standard-efficiency and energy-efficient motors are compared. Pay back periods when replacing standard-efficiency motors with energy-efficient motors, with reference to Bahrain's market, have been discussed. Finally the energy-conservation capability of EE motors in the petrochemical industry has been discussed.     

Applications of variable speed drive (VSD) in electrical motors energy savings

Most motors are designed to operate at a constant speed and provide a constant output; however, modern technology requires different speeds in many applications where electric motors are used. A variable speed drive (VSD) is a device that regulates the speed and rotational force, or output torque of mechanical equipment. Effects of applying VSDs are in both productivity improvements and energy savings in pumps, fans, compressors and other equipment. Variable speed drive technology and the importance of controlling the speed of existing motors have fascinated many attentions in the last years with the advent of new power devices and magnetic materials. This paper is a comprehensive review on applications of VSD in electrical motors energy savings. The aim is to identify energy saving opportunities and incorporated costs of applying variable speed drives to the existing applications of electrical motors. Subsequently, economic analysis, payback period and the effect of current and voltage harmonics generated by VSDs are presented. Authors are hopeful to provide useful information for future variable speed drive applications like fans, pumps, chillers, ventilators and heaters.     

浅谈工厂电气技术中节能技术的应用

现今工业产品生产成本构成很多,其中用电成本是绝对不可忽视的,由于工厂供电系统中的用电设备运行时会产生大量无功功率损耗,因此,从工厂供电系统中无功消耗的种类出发,减少设备投资,降低企业用电成本成为大家所共同关注的。文章主要从厂用电的节能设计、节能设备应用、厂用电管理等方面进行阐述,目的是降低厂用电量。     

Reducing the Costs of Paying for Consumed Electric Energy by Utilizing Solar Energy

The use of a low-power solar network and standalone power plants is the most promising for the needs of the housing and utilities sector, small industrial enterprises, social and public health facilities, recreation areas, remote objects, and agricultural industries; this will make it possible to reduce the load on the energy system at peak moments, as well as to decrease losses when transporting electric energy in its elements. It is assumed that the minimum value of the unit cost of generated electric energy is used as the criterion for configuring and selecting the parameters of solar power equipment, which will make it possible to set up an economically feasible additional power supply to the consumer, since it excludes the use of storage devices and rearrangement of the power supply system.     

An application of energy and exergy analysis in agricultural sector of Malaysia

Thermodynamic losses usually take place in machineries used for agricultural activities. Therefore, it is important to identify and quantify the losses in order to devise strategies or policies to reduce them. An exergy analysis is a tool that can identify the losses occurred in any sector. In this study, an analysis has been carried out to estimate energy and exergy consumption of the agricultural sector in Malaysia. Energy and exergy efficiencies have been determined for the devices used in the agricultural sector of Malaysia, where petrol, diesel and fuel oil are used to run the machineries. Energy and exergy flow diagrams for the overall efficiencies of Malaysian agricultural sector are presented as well. The average overall energy and exergy efficiencies of this sector were found to be 22% and 20.728%, respectively, within the period from 1991 to 2009. These figures were found to be lower than those of Norway but higher than Turkey.     

Chillers energy consumption, energy savings and emission analysis in an institutional buildings

Chillers consume more than 40% of the total energy used in the commercial and industrial buildings for space conditioning. In this paper, energy consumption by chillers and chilled water pumps, condenser pumps and fan motors has been estimated using data collected by a walkthrough energy audit for the 16 faculties of the University of Malaya. It has been estimated that chillers and motors and pumps used in chillers consume 10,737 MWh (i.e. 51% of total energy consumption) of electric energy for different percentage of loadings. As chillers are major energy users, variable speed drives are applied in chillers to reduce their energy consumption. It has been estimated that about 8368 MWh annual energy can be saved by using efficient chillers at different loadings. It has also been found that about 23,532 MWh annual energy can be saved for chilled water supply pumps, condenser pumps and cooling tower fan motors by matching required speeds using variable speed drives for 60% of speed reduction. About 1,274,692 kg of CO₂ emission could be avoided for using energy efficient chillers at 50% load. It has been also found that about 2,426,769 kg CO₂ emission can be reduced by using variable speed drives for 60% speed reductions. Payback periods found to be only few months for using variable speed drives in chilled water pumps, condensers and fan motors.     

An evaluation of the potential of the use of wasted hydroelectric capacity to produce hydrogen to be used in fuel cells in order to decrease CO2 emissions in Brazil

The use of water wasted in hydroelectric plants as normalization dam excess, which constitute a hydrodynamic potential useful to generate electric energy which can be subsequently used to produce hydrogen and its subsequent consumption in fuel cells, has been considered as an alternative for hydraulic energy-rich countries like Brazil. The case is examined in which all the water wasted in the hydroelectric plants, spilled by dam gates to maintain acceptable water levels, from the 101 largest Brazilian hydroelectric plants was used to produce hydrogen. During the year of 2008, the electric energy produced from this utilisation would have been equivalent to 106.2 TWh, an amount that corresponds to an increase of ca. 30% of the total electric energy produced in the country. Furthermore, if this amount of hydrogen was used in the replacement of internal combustion vehicles by fuel cells, this would have prevented the production of 2,000,000 tons of CO₂ emissions per day. The economic balance (cost of electricity produced using the wasted water minus cost of gasoline consumed) indicates a savings of ca. 200 million US$. This plan would also significantly decrease production and release of greenhouse gases.     

Characterization of energy use in 300 mm DRAM (Dynamic Random Access Memory) wafer fabrication plants (fabs) in Taiwan

Driven by technology advances and demand for enhanced productivity, migration of wafer fabrication for DRAM (Dynamic Random Access Memory) toward increased wafer size has become the fast-growing trend in semiconductor industry. Taiwan accounts for about 18% of the total DRAM wafer production in the world. The energy use required for operating wafer fabrication plants (fabs) is intensive and has become one of the major concerns to production power reliability in the island. This paper characterizes the energy use in four 300 mm DRAM wafer fabs in Taiwan through performing surveys and on-site measurements. Specifically, the objectives of this study are to characterize the electric energy consumption and production of 300 mm DRAM fabs by using various performance metrics, including PEI ((production efficiency index), annual electric power consumption normalized by annual produced wafer area) and EUI ((electrical utilization index), annual electric power consumption normalized by UOP (units of production), which is defined as the product of annual produced wafer area and the average number of mask layers of a wafer). The results show that the PEI and EUI values are 0.743 kWh/cm² and 0.0272 kWh/UOP, respectively. Using EUI in assessing energy efficiency of the fab production provides more consistent comparisons than using PEI alone.     

抽油机井节电设备配置优化试验与应用

油井抽油机、电机、电控箱组合配置有利于节能（电能）。以吨液百米耗电量为指标,考察了7组不同抽油机、电机、电控箱组合配置在4种举升高度（200m、400m、600m、800m）下的系统效率。耗电设备的合理配置,可以提高系统效率,降低吨液耗电量,节能（电能）效果显著。