首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 277 毫秒
1.
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.  相似文献   

2.
Electric motors consume in between 30% and 80% of the total industrial energy use for few selected countries around the world. It was identified that many motors are operated under loaded conditions. In some cases, motors are operated even at 3-16% of their full loads. These low loads can be optimized with the application of variable speed drives (VSD) to match the load requirements. Based on the estimation, it has been found that annually about 1,865,925 MWh of energy can be saved for 60% speed reduction when VSDs are used. It was also found that about 2,122,675 tons CO2emission could be avoided annually by using VSDs for Low Tension (LT) motors for 60% speed reduction. It was also estimated that annually about 4,600,386 MWh of energy can be saved for High Tension (HT) motors for 60% speed reduction using VSDs. The average payback period (PBP) for implementing VSDs for LT and HT motors found to be very low (i.e. about 2 days). In this particular study it is observed that installing both LT and HT capacitors to improve power factor found to be not economically viable owing to low level of energy savings.  相似文献   

3.
An end-use energy analysis in a Malaysian public hospital   总被引:2,自引:0,他引:2  
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.  相似文献   

4.
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.  相似文献   

5.
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.  相似文献   

6.
Electric motors consume 30-80% of total industrial energy around the world. This study estimates the economic viability of replacing rewound and standard motors with high efficiency motors (HEMs) in the industrial sector. The efficiency of a motor is degraded when it is rewound and it is better to rewind a larger motor compared with a smaller motor. It was found that a HEM can save on average 5.5% of energy compared with a standard motor. In addition, the payback period was found to be reasonable when a motor is operated at a 50% load. HEMs will also save a sizeable amount of energy and reduce emissions. It was estimated that 67,868 MWh/year energy and US$ 4,343,531 per year could be saved by introducing HEMs. By contrast, 44,582 tons of CO2, 333 tons of SO2 and 122 tons of NOx emissions could be reduced through the aforementioned energy savings. This study found that rewound motors of a larger size and HEMs are economically viable.  相似文献   

7.
In this paper an analysis of energy use and energy conservation in the Malaysian rubber producing industries is presented. It has been found that rubber industries consume a substantial amount of energy. Excessive use of energy is usually associated with many industrial plants worldwide, and rubber plants are no exception. This study is based on the realization that enormous potential exists for cost-effective improvements in the existing energy-using equipment. Through the method of a walkthrough energy audit, power rating, operation time of energy-consuming equipment/machineries and power factor were collected. The data were then analyzed to investigate the breakdown of end-use equipment/machineries energy use. The results of the energy audit in the Malaysian rubber and rubber producing industries showed that the electric motor accounts for a major fraction of total energy consumption followed by pumps, heaters, cooling systems and lighting. Since the electric motor takes up a substantial amount of the total energy used in rubber industries, energy-savings strategies such as the use of high efficient motors, and variable speed drive (VSD) have been used to reduce energy consumption of motors used in rubber industries. Energy-savings strategies for compressed-air systems, boilers, and chillers have also been applied to estimate energy and cost savings. It has been found that significant amount of energy and; utility bills can be saved along with the reduction of emission by applying the foretold strategies for energy using machineries in the rubber industries.  相似文献   

8.
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.  相似文献   

9.
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.  相似文献   

10.
This paper aims to identify the main drivers behind energy intensity changes of the Jordanian industrial sector and to introduce the impact of energy efficient measures within the Jordanian industrial sector. To achieve these objectives, two empirical models were developed for electricity and fuel intensities, respectively of the Jordanian industrial sector based on multivariate linear regression. It was found that the structural effect, electricity prices, capacity utilizations and number of employees are the most important variables that affect changes of electricity intensity while fuel prices, capacity utilizations and number of employees factors are the most important variables that affect fuel intensity. The results show that multivariate linear regression model can be used adequately to simulate industrial energy intensity with very high coefficient of determination. Also, the impact of implementing energy saving technologies, such as use of high efficiency motors (HEMs), optimize motor size, variable speed drives (VSDs), bare steam pipes insulations, steam leak prevention, steam traps repair, and adjustment of boiler air/fuel ratio were investigated and found to be significant. Without such basic energy conservation and management programs, energy consumptions and associated GHG emissions for the industrial sector are predicted to rise by 25% and 23%, respectively in the year 2021. If these measures are implemented on a gradual basis, over the next decade, industrial energy consumption is predicted to rise at a lower rate, reaching 11.9% for same period with low/no cost actions. This would yield an estimated annual emission reductions of 570×103 t. In addition, the total installed capacity cost savings is estimated to be around 81.9 million US$ by year 2021.  相似文献   

11.
White certificate schemes mandate energy companies to promote energy efficiency with flexibility mechanisms, including the trading of energy savings. A unified framework is used to estimate the costs and benefits of the schemes implemented in Great Britain in 2002, in Italy in 2005 and in France in 2006. ‘Negawatt-hour cost’ estimates reach 0.009€/kWh saved in Great Britain and 0.037€/kWh saved in France, which compares favourably to energy prices in those countries. Moreover, the benefits of reduced energy bills and CO2 emissions saved exceed the costs; thus, white certificate schemes pay for themselves. Overall, the policy instrument is cost-effective and economically efficient. A closer look at the differences amongst countries provides general insights about the conceptualization of the instrument: (a) Compared to utility demand-side management, to which they are related, white certificate schemes provide more transparency about energy savings, but less transparency around costs; (b) the substantial efficiency discrepancy between the British scheme and its French counterpart can be explained by differences in technological potentials, coexisting policies and supply-side systems in these countries and (c) the nature and amount of costs influence compliance strategies. Notably, if energy suppliers are allowed to set their retail price freely, they tend to grant subsidies to end-use consumers for energy efficient investments.  相似文献   

12.
This document shows the importance of policies for electric energy savings and efficient energy utilization in power planning. The contributions of economic, social, and environmental items were evaluated according to their financial effects in the delay of investments, reduction of production costs and decrement of environmental emissions. The case study is Baja California, México; this system has a unique primary source: geothermal energy. Whether analyzing the planning as usual or planning from the supply side, the forecast for 2005–2025 indicates that 4500 MW additional installed capacity will be required (3-times current capacity), representing an investment that will emit 12.7 Mton per year of CO2 to the atmosphere and will cost US$2.8 billion. Systemic planning that incorporates polices of energy savings and efficiency allows the reduction of investments and pollutant emissions. For example, a reduction of 20% in the growth trend of the electricity consumption in the industrial customers would save US$10.4 billion over the next 20 years, with a potential reduction of 1.6 Mton/year of CO2. The increase in geothermal power generation is also attractive, and it can be combined with the reduction of use and energy losses of utilities, which would save US$13.5 billion and prevent the discharge of 8.5 Mton/year of CO2.  相似文献   

13.
Energy efficiency improvement is an effective way of reducing energy demand and CO2 emissions. Although the overall final energy savings potential in chemical industry has been estimated in a few countries, energy efficiency potentials by concrete measures applicable in the sector have been scarcely explored and their associated costs are hardly analyzed. In Switzerland, the production of chemicals and pharmaceuticals exceeds all other industrial sectors in terms of energy use and CO2 emissions, and it accounted for 22% of the total industry's overall final energy demand and 25% of the CO2 emissions related to non‐renewable energy sources in 2016. In this study, the economic potentials for energy efficiency improvement and CO2 emissions reduction in the Swiss chemical and pharmaceutical industry are investigated in the form of energy efficiency cost curves. The economic potential for final energy savings and CO2 abatement based on energy‐relevant investments is estimated at 15% and 22% of the sector's final energy use and fossil fuel‐related CO2 emissions in 2016, respectively. Measures related to process heat integration are expected to play a key role for final energy savings. The economic electricity savings potential by improving motor systems is estimated at 15% of the electricity demand by these systems in 2016. The size of economic potential of energy efficiency improvement across the sector decreases from 15% to 11% for 0.5 times lower final energy prices while the size increases insignificantly for 1.5 times higher final energy prices. The additional power generation potential based on Combined Heat and Power plants is estimated at 14 MW for 2016. This study is a contribution to the so far limited international literature on economic energy efficiency measures applicable in this heterogeneous sector and can support policy development. The results for specific costs of energy efficiency measures can also be adapted to other parts of the world by making suitable adjustments which in return may provide useful insights for decision makers to invest in economically viable clean energy solutions.  相似文献   

14.
Energy efficiency and savings strategies in the combustion based industrial process heating has been reviewed comprehensively and presented in this paper. This work compiles latest literatures in terms of thesis, journal articles, conference proceedings, web materials, reports, books, handbooks on industrial process heating systems in the industrial sector. Different types of equipment used (i.e., recuperator, regenerators, heat wheels, heat pipes, economizers, etc.) and energy savings are reviewed in various industrial processes heating. Based on the review results, it is found that significant amounts of energy could be saved by using heat recovery system in the industrial process heating. By using recuperator up to 25% energy can be saved in the furnace. In the case of boiler, by using economizers 10% to 20% energy can be saved. Economic analysis shows that the payback period of recuperator and economizer are normally less than 2 years. It is also found that the payback period is lower when operating hour is comparatively high.  相似文献   

15.
While ice storage systems are designed according to a defined strategy for warm day loads, it is interesting to consider other conventional control strategies for mid-season day loads. Three different charging–discharging control strategies are applied to an existing cooling plant and compared in terms of operating costs and energy consumption. A cooling plant model is built. A time stage equal to 15 min is considered to simulate numerically a whole charging–discharging process and compare the different control strategies. These simulations take into account existing technical constraints and set points. EES software is used. The operating costs of the cooling plant are evaluated by taking into account both the energy and the demand cost rate. It is shown that an ice storage system can allow savings of operating costs. However, they can increase energy consumption.  相似文献   

16.
《Applied Energy》1999,63(1):53-74
Greenhouse gas emissions in Lebanon mainly come from energy activities, which are responsible for 85% of all CO2 emissions. The CO2 emissions from energy use in manufacturing industries and construction represent 24% of the total emissions of the energy sector. Lebanese manufacturers' accounted for 39.15 million gigajoules of fuel consumption for heat and power generation in 1994, including both fuel used directly and fuel burned remotely to generate electricity used in the sector. In addition to being processed by combustion, CO2 is generated in calcining of carbonates in the manufacture of cement, iron and glass. Electricity, the most expensive form of energy, represented 25.87% of all fuel used for heat and power. Residual fuel oil and diesel, which are used mainly in direct combustion processes, represent 26.85 and 26.55% of all energy use by industry, respectively. Scenarios for future energy use and CO2 emissions are developed for the industrial sector in Lebanon. The development of the baseline scenario relied on available data on major plants' outputs, and on reported amounts of fuels used by the industrial sector as a whole. Energy use in industry and the corresponding greenhouse gas (GHG) emissions for Lebanon are projected in baseline scenarios that reflect technologies, activities and practices that are likely to evolve from the base year 1994 to year 2040. Mitigation work targets a 15% of CO2 emissions from the baseline scenario by year 2005 and a 20–30% reduction of CO2 emissions by year 2040. The mitigation options selected for analysis are screened on the basis of GHG emissions and expert judgement on the viability of their wide-scale implementation and economic benefits. Using macroeconomic assessment and energy price assumptions, the final estimates of potential GHG emissions and reduction costs of various mitigation scenarios are calculated. The results show that the use of efficient electric motors, efficient boilers and furnaces with fuel switching from fuel oil to natural gas has the largest impact on GHG emissions at a levelized annual cost that ranges from −20 to −5 US$/tonne of CO2 reduced. The negative costs are indicative of direct savings obtained in energy cost for those mitigation options.  相似文献   

17.
End-use electricity efficiency improvements offer an inexpensive way to reduce power shortages. The present study estimates the potential of demand-side management efficiency improvement targeted at (1) short-term efficiency improvement (agricultural pump rectification) that can provide immediate relief, and (2) long-term efficiency improvement (appliance standards such as AC and refrigerator, new agricultural pump purchase and pump replacement) for Gujarat state in India. The methodology includes the calculation of cost of conserved energy for each technology, which works out to be (−1.18) US$ cents/kW h for new agriculture pump sets, 1.03 US$ cents/kW h for refrigerators and 5.21 US$ cents/kW h for air conditioners. The price of power varies around 1.13 US$ cents to 12.1 cents/kW h in Gujarat. The annual energy savings from the selected energy-efficient technologies are approximately 8767 GW h over a period of 10 yr, while the estimated peak power savings are about 1814 MW, large enough to eliminate one-fourth of the state's electricity shortages. Also, the estimated CO2 emissions savings are about 7715 Giga grams (Gg) from implementation of the selected energy efficiency measures over a period of 10 yr.  相似文献   

18.
Six different strategies have recently been proposed for the European Union (EU) energy system in the European Commission's report, Energy Roadmap 2050. The objective for these strategies is to identify how the EU can reach its target of an 80% reduction in annual greenhouse gas emissions in 2050 compared to 1990 levels. None of these scenarios involve the large-scale implementation of district heating, but instead they focus on the electrification of the heating sector (primarily using heat pumps) and/or the large-scale implementation of electricity and heat savings. In this paper, the potential for district heating in the EU between now and 2050 is identified, based on extensive and detailed mapping of the EU heat demand and various supply options. Subsequently, a new ‘district heating plus heat savings’ scenario is technically and economically assessed from an energy systems perspective. The results indicate that with district heating, the EU energy system will be able to achieve the same reductions in primary energy supply and carbon dioxide emissions as the existing alternatives proposed. However, with district heating these goals can be achieved at a lower cost, with heating and cooling costs reduced by approximately 15%.  相似文献   

19.
Using light-emitting diodes (LEDs) can significantly reduce the current household lighting energy use in Finland during 2020–2050. Our calculations show that the potential of using LEDs in reducing household lighting energy use and corresponding CO2 emissions in Finland during 2020–2050 can be significant. Reductions from the current level of Finnish household lighting energy use (1.8 TWh/a) were 59 % in 2020, 72 % in 2030 and 78 % in 2050, when a high LED penetration was assumed. Lighting energy savings in 2020 would mean a 1.3 % reduction from the current total electricity use in Finland (84.2 TWh/a). The starting point in 2012 was that the share of incandescent lamps was 32 % and the share of LED lamps 6 % of the total amount of lamps in an average household. Using the current average emissions factor (current electricity production structure), the saved amount of energy in 2020 means 234,000 tonnes of CO2. Using the marginal emissions factor, the saved amount of energy means 920,000 tonnes of CO2 emissions.  相似文献   

20.
Atul Kumar  Tara C. Kandpal   《Solar Energy》2005,78(2):321-329
An attempt to estimate the potential of solar crop drying for some selected cash crops in India has been made. The amount of cash crops that can be dried by solar dryers and the required aperture area of solar dryers have been estimated. Estimates for unit cost of solar drying for different crops have also been worked out. The potential of net fossil CO2 emissions mitigation due to the amounts of different fuels that would be saved by solar drying has been estimated along with the unit cost of CO2 emissions mitigation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号